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Quantum Paradox Experiment Puts Einstein to the Test May Lead to More Accurate Clocks and Sensors – SciTechDaily

A clock moving in superposition of different speeds would measure a superposition of different elapsing times in a quantum version of the famous twin paradox of special relativity. Credit: Magdalena Zych

More accurate clocks and sensors may result from a recently proposed experiment, linking an Einstein-devised paradox to quantum mechanics.

University of Queensland physicist Dr. Magdalena Zych said the international collaboration aimed to test Einsteins twin paradox using quantum particles in a superposition state.

The twin paradox is one of the most counterintuitive predictions of relativity theory, Dr. Zych said. It says that time can pass at different speeds for people at different distances to an enormous mass or traveling with different velocities.

For example, relative to a reference clock far from any massive object, a clock closer to a mass or moving at high speed will tick slower. This creates a twin paradox, where one of a pair of twins departs on a fast-speed journey while the other stays behind. When the twins reunite, the traveling twin would be much younger, as different amounts of time have passed for each of them.

Its a mind-blowing effect featured in popular movies like Interstellar but its also been verified by real world experiments, and is even taken into consideration in order for everyday GPS technology to work.

The team included researchers from the University of Ulm and Leibniz University Hannover and found how one could use advanced laser technology to realize a quantum version of Einsteins twin paradox.

In the quantum version, rather than twins there will be only one particle traveling in a quantum superposition.

A quantum superposition means the particle is in two locations at the same time, in each of them with some probability, and yet this is different to placing the particle in one or the other location randomly, Dr. Zych said.

Its another way for an object to exist, only allowed by the laws of quantum physics.

The idea is to put one particle in superposition on two trajectories with different speeds, and see if a different amount of time passes for each of them, as in the twin paradox. If our understanding of quantum theory and relativity is right, when the superposed trajectories meet, the quantum traveler will be in superposition of being older and younger than itself.

This would leave an unmistakable signature in the results of the experiment, and thats what we hope will be found when the experiment is realized in the future.

It could lead to advanced technologies that will allow physicists to build more precise sensors and clocks potentially, a key part of future navigation systems, autonomous vehicles and earthquake early-warning networks.

The experiment itself will also answer some open questions in modern physics.

A key example is, can time display quantum behavior or is it fundamentally classical? Dr. Zych said. This question is likely crucial for the holy grail of theoretical physics: finding a joint theory of quantum and gravitational phenomena. Were looking forward to helping answer this question, and tackling many more.

For more on this study, read Physicists Put Einstein to the Test With a Quantum-Mechanical Twin Paradox.

Reference: Interference of clocks: A quantum twin paradox by Sina Loriani, Alexander Friedrich, Christian Ufrecht, Fabio Di Pumpo, Stephan Kleinert, Sven Abend, Naceur Gaaloul, Christian Meiners, Christian Schubert, Dorothee Tell, tienne Wodey, Magdalena Zych, Wolfgang Ertmer, Albert Roura, Dennis Schlippert, Wolfgang P. Schleich, Ernst M. Rasel and Enno Giese, 4 October 2019, Science Advances.DOI: 10.1126/sciadv.aax8966

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Quantum Paradox Experiment Puts Einstein to the Test May Lead to More Accurate Clocks and Sensors - SciTechDaily

A Newly Seen Quantum Symmetry Can Lead To Insights To The Workings Of The Universe – Forbes

If you work up from first principles, much of what we understand about the Universe and how it works is through symmetries. If a transformation is symmetric, the properties of a system can be retained if the system is transformed. A research team from the University of Washington has shown for one of the first times a new type of symmetry in quantum systems. This experiment may lead to further advancements in physics, especially in the realm of quantum computing.

There are various ways that a system can be symmetric. P, or parity, symmetry means that the orientation can be swapped. Such a symmetry is what we see in our bodies. Our right hand is a mirror image of our left hand. C, or charge, symmetry means that each particle is swapped with its own anti-particle, effectively changing its charge. Finally, T, or time, symmetry is time, meaning that the system follows the same laws of physics whether the system runs forwards or backwards in time.

Your hands illustrate P, or parity symmetry - one hand is the mirror image of the other.

Understanding symmetries within the Universe allows us to construct various laws of physics, from the conservation of energy or the conservation of momentum.

Symmetries are often broken, especially when looking at one of these properties at a time. However, the Standard Model predicts that together, these symmetries should hold. This is called CPT symmetry.

The research, from the lab of Dr. Kater Murch at Washington University in St. Louis and led by Dr. Mahdi Naghiloo shows for one of the first times PT (or parity-time) symmetry being held in a quantum system.

The group used a qubit - or a superconducting circuit - to make a three-state quantum system. This system has three excited states. The first typically decays to the ground state, while the other two are coupled. The team was able to select only instances where the qubit did not decay into the ground state which led to the effective PT symmetry.

Exploration of PT symmetry - both when it holds and when it is broken - can lead to deeper understandings of the world of quantum physics.

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A Newly Seen Quantum Symmetry Can Lead To Insights To The Workings Of The Universe - Forbes

UWMadison physicist awarded Packard Fellowship – University of Wisconsin-Madison

Shimon Kolkowitz, a University of WisconsinMadison assistant professor of physics, has been selected as one of 22 members of the 2019 class of Packard Fellows for Science and Engineering.

The fellowship, awarded to early-career scientists from across the U.S., provides $875,000 of funding over five years. Kolkowitz will use the funds to develop his research program in ultra-precise atomic clocks, which he will use to investigate such fundamental aspects of physics as the relationship between quantum mechanics and gravity and the nature of dark matter.

Shimon Kolkowitz is the third UWMadison physics professor to be named a Packard Fellow in the 32 years of the award. Photo: Steven Burrows / JILA

These clocks are the most precise instruments that humankind has ever built, Kolkowitz says. Im interested in asking, How does that precision give us access to new physics?

One of the first research areas Kolkowitz plans to explore is a new test of Einsteins general theory of relativity. When first developing the theory, Einstein suggested that people in a closed elevator could not tell the difference between the elevator on Earth under the influence of gravity and the elevator accelerating through space in zero gravity.

Thats called the Einstein equivalence principle, and it is at the heart of general relativity. The predictions of general relativity have been tested in a number of different ways and have always been confirmed, Kolkowitz explains. But the basic question of, Can I tell the difference between acceleration and gravity? has not been directly tested. And I think it will be a lot of fun and really cool to directly realize that thought experiment in my lab.

Atomic clocks keep time by measuring the differences between energy levels of the electrons in atoms. The clocks timekeeping precision is affected by many factors, such as the surrounding environment, the temperature of the atoms, and the type of atom used. The atomic clocks constructed in Kolkowitzs lab are made of strontium atoms that have both been gathered into a small sphere and cooled to just above absolute zero the coldest temperature that can exist by lasers.

Kolkowitzs ultra-precise atomic clock, an ultra-high vacuum containing strontium atoms that are trapped and cooled to 1/1000th of a degree above absolute zero by lasers, will test Einsteins general theory of relativity. Photo: Shimon Kolkowitz

The general theory of relativity says that gravity affects the passage of time, so two atomic clocks at different heights, which experience slight differences in the strength of gravity, will tick at different rates. Currently, that time difference has been observed between two atomic clocks that are about a foot apart in height. A unique feature of Kolkowitzs clock design is that it allows two clocks to exist in the same environment. As a result, in the first set of experiments he plans to conduct, he expects they will be able to measure differences in time due to gravity at centimeter or millimeter height differences.

Next, he wants to measure differences in time between two accelerating clocks that are separated by the same distance this time horizontally instead of vertically to take the effects of gravity out of the equation.

According to the equivalence principle, we should see the same disagreement between the two clocks from the acceleration as from gravity, Kolkowitz says. And thats an effect that has never been observed before.

The Packard Fellowship gives me the freedom to explore research avenues that might not have obvious or immediate applications, but that can inspire the imagination, and that will hopefully lead in unexpected directions.

Shimon Kolkowitz

Kolkowitz admits he is not entirely sure what the implications of these experiments may be. One possibility he is exploring with theoretical physics colleagues is whether related experiments with these quantum-physics-based clocks can complement or improve upon high energy particle physics experiments in the search for new physics, such as the nature of dark matter or dark energy.

These experiments are kind of out there, Kolkowitz says. The Packard Fellowship gives me the freedom to explore research avenues that might not have obvious or immediate applications, but that can inspire the imagination, and that will hopefully lead in unexpected directions.

Professor Kolkowitzs innovative research onprecision metrology with quantum systems is original and highly relevant for quantum information science, says Sridhara Dasu, professor and chair of the physics department at UWMadison. We look forward to his continued success in establishing a flourishing research program in the department.

Kolkowitz is the third UWMadison physics professor to be named a Packard Fellow in the 32 years of the award, after Thad Walker (1992) and Cary Forest (1998). Previously named Packard Fellows include Kolkowitzs former advisor as well as two Nobel laureates.

I feel that Im following in the footsteps of some very impressive people, and thats a real honor for me, Kolkowitz says.

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UWMadison physicist awarded Packard Fellowship - University of Wisconsin-Madison

University’s new supercomputer, Traverse, to aid plasma physics and fusion research – The Daily Princetonian

Photo Courtesy of Denise Applewhite / Office of Communications

The Universitys High-Performance Computing Research Center (HPCRC) has acquired a new supercomputer, named Traverse, which will aid research at the Universitys Plasma Physics Laboratory (PPPL), as well as other University programs.

The addition joins six other computing clusters: Tiger, Dell, and Perseus, which are the largest and reserved primarily for faculty, as well as Nobel, Adroit, and Tigressdata, which are available to students. All the clusters are housed in a building on the Forrestal campus, about three miles from the main campus.

Supercomputers require high amounts of energy, and HPCRC typically uses 1.8 megawatts of electricity and is equipped with backup generators. The clusters can also overheat, which requires ventilating them with cooled air. The facility is efficient enough to have earned a LEED Gold rating.

Thanos Panagiotopoulos, the chair of the chemical and biological engineering department, said that Traverse will allow Princetons Chemistry in Solution and at Interfaces (CSI) lab to model the interactions of a few hundred molecules at a time.

We do problems involving very large-scale calculations that connect quantum mechanics with the collective properties of water and aqueous solutions, Panagiotopoulos said. The simulations usually last only on the order of a few picoseconds but can help CSI understand the atomistic dynamics of various materials.

Roberto Car, director of CSI and the Ralph W. *31 Dornte Professor in Chemistry at the University, said that his group of researchers now uses a new, more efficient mathematical construction, called a deep neural network, which uses machine learning to compute the classical mechanics forces in any number of arrangements that share the same statistical probability. Researchers derive the interaction potentials from density functional theory, which considers the quantum mechanics of the atoms in their ground states.

Having access to that kind of machine at Princeton will allow us to do this work on our code and experiment with the capabilities offered by this architecture, Car said.

Traverse has a similar architectural structure to Summit, the most powerful supercomputer in the world, housed at Oak Ridge National Laboratory. Traverse is a 1.4-petaflop system, making it capable of 1.4 million billion floating-point calculations per second. It is on the TOP500 list, a ranking of the 500 most powerful supercomputers based on standard tests.

Panagiotopoulos and Car noted that Traverse will soon be overtaken by more powerful supercomputers. Car predicted that exascale systems, which would be capable of a billion billion calculations per second and function 1,000 times faster than petascale ones, will be built in the next few years. He noted that PPPL will likely be able to use technology developed at Oak Ridge.

What sets Traverse apart from the previous HPCRC clusters is its architecture described by Car as a hybrid architecture that consists of CPU [central processing unit] and GPUs [graphics processing units]. The clusters were built by IBM, and the GPUs were supplied by Nvidia, which sells GPUs for many personal computers and gaming systems.

Car said the first exascale supercomputers will share a similar architecture to Traverse, meaning that the work required to adapt the researchers current algorithms to Traverse will remain useful.

Traverse will help PPPL model the movement of plasma in its tokamak NSTX-U, the largest of its kind in the world, to better understand how to control the plasma on a millisecond timescale. PPPL was founded in 1951 and has been working, among other projects, to create a viable fusion reactor potentially capable of generating virtually unlimited energy.

Traverse was financed by the University, and it will be used by graduate students, postdoctoral researchers, and faculty at the University, as well as PPPL, which is managed by the Department of Energy.

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University's new supercomputer, Traverse, to aid plasma physics and fusion research - The Daily Princetonian

Quantum weirdness could allow a person-sized wormhole to last forever – New Scientist News

By Chelsea Whyte

L. CALCADA / EUROPEAN SOUTHERN OBSERVATORY / SCIENCE PHOTO LIBRARY

Fancy a trip down a wormhole? We have never been quite sure whether these portals through space-time could exist long enough for anything to travel through. Now calculations suggest they could stick around for a while perhaps as long as the universe itself.

Wormholes are essentially two black holes connected together. Two types could theoretically exist. A non-traversable wormhole is like a room with two doors that can only be used from the outside the doors are black holes through which things could enter, but never escape. These are not very interesting, as any astronaut who is brave enough to venture in wont be able to make it back to tell the story, says Diandian Wang at the University of California, Santa Barbara.

Traversable wormholes are also possible, but up until now we didnt know whether they could exist for long enough for anything to pass through in practice.

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For such a wormhole to form, space-time needs to change shape from being like a flat sheet to having holes in it. In classical physics, this cant happen. But the rules of quantum mechanics seem to allow for space-time to spontaneously change shape, although this is likely to only be for very short periods.

Wang has now worked on a scenario involving string theory, in which the fundamental ingredient of reality are tiny strings. If one of these strings breaks, it can create a traversable wormhole. It contains energy, and when it breaks, that energy becomes two black holes at each end of the string, says Wang.

Researchers had shown this was a possibility before, but it seemed the energy would force the two black holes to zoom apart from each other, snapping the wormhole.

Now, Wang and his team have calculated that the curvature of space-time could counteract this acceleration, keeping the black holes static and allowing the throat of the wormhole to remain open.This scenario is extremely unlikely, and becomes even more unlikely the longer the wormhole is and the larger the two black holes are.

This means that a wormhole big enough for a person to travel through is much less likely than one through which light could be sent. Thanks to quantum mechanics, though, the probability of either happening isnt zero.

Wangs team also calculated that, once a traversable wormhole exists, it could remain stable for at least as long as the universe has existed and maybe forever.

Our previous work showed that wormholes can be traversable, says Aron Wall at the University of Cambridge. But we did not describe a process to create the wormhole. He says Wangs calculations show how one could be created from scratch.

Wall points out, however, that Wangs wormholes couldnt be used to time travel or move faster than the speed of light. Were you to travel through one, he says, you would still be confined to moving slower than the speed of light.

Journal reference: Classical and Quantum Gravity, DOI: 10.1088/1361-6382/ab436f

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Quantum weirdness could allow a person-sized wormhole to last forever - New Scientist News

Has human evolution reached its peak for cognitive understanding? – The Independent

Despite huge advances in science over the past century, our understanding of nature is still far from complete. Not only have scientists failed to find the holy grail of physics unifying the very large (general relativity) with the very small (quantum mechanics) they still dont know what the vast majority of the universe is made up of. The sought-after theory of everything continues to elude us. And there are other outstanding puzzles, too, such as how consciousness arises from mere matter.

Will science ever be able to provide all the answers? Human brains are the product of blind and unguided evolution. They were designed to solve practical problems impinging on our survival and reproductionnot to unravel the fabric of the universe. This realisation has led some philosophers to embrace a curious form of pessimism, arguing thatthere are bound to be things we will never understand. Human science will therefore one day hit a hard limit and may already have done so.

Some questions may be doomed to remain what the American linguist and philosopher Noam Chomsky called mysteries. If you think that humans alone have unlimited cognitive powers setting us apart from all other animals you have not fully digested Darwins insight that Homo sapiens is very much part of the natural world.

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But does this argument really hold up? Consider that human brains did not evolve to discover their own origins either. And yet somehow we managed to do just that. Perhaps the pessimists are missing something.

Mysterian arguments

Mysterian thinkers give a prominent role to biological arguments and analogies. In his 1983 landmark bookThe Modularity of Mind,the late philosopher Jerry Fodor claimed that there are bound to be thoughts that we are unequipped to think.

Similarly, philosopher Colin McGinn has argued in a series of books and articles that all minds suffer from cognitive closure with respect to certain problems. Just as dogs or cats will never understand prime numbers, human brains must be closed off from some of the worlds wonders. McGinn suspects that the reason why philosophical conundrums such as the mind-body problem how physical processes in our brain give rise to consciousness prove to be intractable is that their true solutions are simply inaccessible to the human mind.

If McGinn is right that our brains are simply not equipped to solve certain problems, there is no point in even trying, as they will continue to baffle and bewilder us. McGinn himself is convinced that there is, in fact, a perfectly natural solution to the mind-body problem, but that human brains will never find it.

Even the psychologist Steven Pinker, someone who is often accused of scientific hubris himself, is sympathetic to the argument of the mysterians. If our ancestors had no need to understand the wider cosmos in order to spread their genes, he argues, why would natural selection have given us the brainpower to do so?

Mind-boggling theories

Mysterians typically present the question of cognitive limits in stark, black-or-white terms: either we can solve a problem, or it will forever defy us. Either we have cognitive access or we suffer from closure. At some point, human inquiry will suddenly slam into a metaphorical brick wall, after which we will be forever condemned to stare in blank incomprehension.

Another possibility, however, which mysterians often overlook, is one of slowly diminishing returns. Reaching the limits of inquiry might feel less like hitting a wall than getting bogged down in a quagmire. We keep slowing down, even as we exert more and more effort, and yet there is no discrete point beyond which any further progress at all becomes impossible.

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There is another ambiguity in the thesis of the mysterians, which my colleague Michael Vlerick and I have pointed out in an academic paper. Are the mysterians claiming that we will never find the true scientific theory of some aspect of reality, or alternatively, that we may well find this theory but will never truly comprehend it?

In the science fiction series The Hitchhikers Guide to The Galaxy, an alien civilisation builds a massive supercomputer to calculate the Answer to the Ultimate Question of Life, the Universe and Everything. When the computer finally announces that the answer is 42, no one has a clue what this means (in fact, they go on to construct an even bigger supercomputer to figure out precisely this).

Is a question still a mystery if you have arrived at the correct answer, but you have no idea what it means or cannot wrap your head around it? Mysterians often conflate those two possibilities.

In some places, McGinn suggests that the mindbody problem is inaccessible to human science, presumably meaning that we will never find the true scientific theory describing the mindbody nexus. At other moments, however, he writes that the problem will always remain numbingly difficult to make sense of for human beings, and that the head spins in theoretical disarray when we try to think about it.

This suggests that we may well arrive at the true scientific theorybut it will have a 42-like quality to it. But, then again, some people would argue that this is already true of a theory like quantum mechanics. Even the quantum physicist Richard Feynman admitted, I think I can safely say that nobody understands quantum mechanics.

Would the mysterians say that we humans are cognitively closed to the quantum world? According to quantum mechanics, particles can be in two places at onceor randomly pop out of empty space. While this is extremely hard to make sense of, quantum theory leads to incredibly accurate predictions. The phenomena of quantum weirdness has been confirmed by several experimental tests, and scientists are now also creating applications based on the theory.

Mysterians also tend to forget how mind-boggling some earlier scientific theories and concepts were when initially proposed. Nothing in our cognitive make-up prepared us for relativity theory, evolutionary biology or heliocentrism.

As the philosopher Robert McCauley writes: When first advanced, the suggestions that the Earth moves, that microscopic organisms can kill human beings, and that solid objects are mostly empty space were no less contrary to intuition and common sense than the most counterintuitive consequences of quantum mechanics have proved for us in the 20th century.McCauleys astute observation provides reason for optimismnot pessimism.

Mind extensions

But can our puny brains really answer all conceivable questions and understand all problems? This depends on whether we are talking about bare, unaided brain poweror not. Theres a lot of things you cant do with your naked brain. But Homo sapiens is a tool-making species, and this includes a range of cognitive tools.

For example, our unaided sense organs cannot detect UVlight, ultrasound waves, X-rays or gravitational waves. But if youre equipped with some fancy technology you can detect all those things. To overcome our perceptual limitations, scientists have developed a suite of tools and techniques: microscopes, X-ray film, Geiger counters, radio satellites detectors and so forth.

All these devices extend the reach of our minds by translating physical processes into some format that our sense organs can digest. So are we perceptually closed to UV light? In one sense, yes. But not if you take into account all our technological equipment and measuring devices.

Through Einsteins Theory of Relativity we can understand that gravity causes shifts in the fabric of space-time (iStock)

In a similar way, we use physical objects (such as paper and pencil) to vastly increase the memory capacity of our naked brains. According to the British philosopher Andy Clark, our minds quite literally extend beyond our skins and skulls, in the form of notebooks, computers screens, maps and file drawers.

Mathematics is another fantastic mind-extension technology, which enables us to represent concepts that we couldnt think of with our bare brains. For instance, no scientist could hope to form a mental representation of all the complex interlocking processes that make up our climate system. Thats exactly why we have constructed mathematical models and computers to do the heavy lifting for us.

Cumulative knowledge

Most importantly, we can extend our own minds to those of our fellow human beings. What makes our species unique is that we are capable of culture, in particular cumulative cultural knowledge. A population of human brains is much smarter than any individual brain in isolation.

And the collaborative enterprise par excellence is science. It goes without saying that a single scientist would not be capable of unravelling the mysteries of the cosmos on her own. But collectively, they do. As Isaac Newton wrote, he could see further by standing on the shoulders of giants. By collaborating with their peers, scientists can extend the scope of their understanding, achieving much more than any of them would be capable of individually.

Today, fewer and fewer people understand what is going on at the cutting edge of theoretical physics even physicists. The unification of quantum mechanics and relativity theory will undoubtedly be exceptionally daunting, or else scientists would have nailed it long ago already.

The same is true for our understanding of how the human brain gives rise to consciousness, meaning and intentionality. But is there any good reason to suppose that these problems will forever remain out of reach? Or that our sense of bafflement when thinking of them will never diminish?

It was only through Einsteins breakthrough that other scientists could make further progress in the field of quantum mechanics (Getty)

In a public debate I moderated a few years ago, the philosopher Daniel Dennett pointed out a very simple objection to the mysterians analogies with the minds of other animals: other animals cannot even understand the questions. Not only will a dog never figure out if theres a largest prime, but it will never even understand the question. By contrast, human beings can pose questions to each other and to themselves, reflect on these questions, and in doing so come up with ever better and more refined versions.

Mysterians are inviting us to imagine the existence of a class of questions that are themselves perfectly comprehensible to humansbut the answers to which will forever remain out of reach. Is this notion really plausible (or even coherent)?

Alien anthropologists

To see how these arguments come together, lets do a thought experiment. Imagine that some extraterrestrial anthropologists had visited our planet around 40,000 years ago to prepare a scientific report about the cognitive potential of our species. Would this strange, naked ape ever find out about the structure of its solar system, the curvature of space-time or even its own evolutionary origins?

At that moment in time, when our ancestors were living in small bands of hunter-gatherers, such an outcome may have seemed quite unlikely. Although humans possessed quite extensive knowledge about the animals and plants in their immediate environment, and knew enough about the physics of everyday objects to know their way around and come up with some clever tools, there was nothing resembling scientific activity.

There was no writing, no mathematics, no artificial devices for extending the range of our sense organs. As a consequence, almost all of the beliefs held by these peopleabout the broader structure of the world were completely wrong. Human beings didnt have a clue about the true causes of natural disaster, disease, heavenly bodies, the turn of the seasons or almost any other natural phenomenon.

Alien anthropologists might overlook the fact that our cognitive abilities have superseded our physical ones (iStock)

Our extraterrestrial anthropologist might have reported the following:

Evolution has equipped this upright, walking ape with primitive sense-organs to pick up some information that is locally relevant to them, such as vibrations in the air (caused by nearby objects and persons) and electromagnetic waves within the 400-700 nanometer range, as well as certain larger molecules dispersed in their atmosphere.

However, these creatures are completely oblivious to anything that falls outside their narrow perceptual range. Moreover, they cant even see most of the single-cell life forms in their own environmentbecause these are simply too small for their eyes to detect. Likewise, their brains have evolved to think about the behaviour of medium-sized objects (mostly solid) under conditions of low gravity.

None of these earthlings has ever escaped the gravitational field of their planet to experience weightlessness, or been artificially accelerated so as to experience stronger gravitational forces. They cant even conceive of space-time curvature, since evolution has hard-wired zero-curvature geometry of space into their puny brains.

In conclusion, were sorry to report that most of the cosmos is simply beyond their ken.

But those extraterrestrials would have been dead wrong. Biologically, we are no different than we were 40,000 years ago but now we know about bacteria and viruses, DNA and molecules, supernovas and black holes, the full range of the electromagnetic spectrum and a wide array of other strange things.

We also know about non-Euclidean geometry and space-time curvature, courtesy of Einsteins general theory of relativity. Our minds have reached out to objects millions of light years away from our planet, and also to extremely tiny objects far below the perceptual limits of our sense organs. By using various tricks and tools, humans have vastly extended their grasp on the world.

The verdict: biology is not destiny

The thought experiment above should be a counsel against pessimism about human knowledge. Who knows what other mind-extending devices we will hit upon to overcome our biological limitations? Biology is not destiny. If you look at what we have already accomplished in the span of a few centuries, any rash pronouncements about cognitive closure seem highly premature.

Mysterians often pay lip service to the values of humility and modestybut, on closer examination, their position is far less restrained than it appears. Take McGinns confident pronouncement that the mindbody problem is an ultimate mystery that we will never unravel. In making such a claim, McGinn assumes knowledge of three things: the nature of the mindbody problem itself, the structure of the human mind, and the reason why never the twain shall meet. But McGinn offers only a superficial overview of the science of human cognitionand pays little or no attention to the various devices for mind extension.

I think its time to turn the tables on the mysterians. If you claim that some problems will forever elude human understanding, you have to show in some detail why no possible combination of mind-extension devices will bring us any closer to a solution. That is a taller order than most mysterians have acknowledged.

Moreover, by spelling out exactly why some problems will remain mysterious, mysterians risk being hoisted by their own petard. As Dennett wrote in his latest book: As soon as you frame a question that you claim we will never be able to answer, you set in motion the very process that might well prove you wrong: you raise a topic of investigation.

In one of his infamous memorandum notes on Iraq, former US secretary of defence Donald Rumsfeldmakes a distinction between two forms of ignorance: the known unknowns and unknown unknowns. In the first category belong things that we know we dont know. We can frame the right questions but we havent found the answers yet. And then there are the things that we dont know we dont know. For these unknown unknownswe cant even frame the questions yet.

It is quite true that we can never rule out the possibility that there are such unknown unknowns and that some of them will forever remain unknown, because for some (unknown) reason human intelligence is not up to the task.

But the important thing to note about these unknown unknowns is that nothing can be said about them. To presume, from the outset, that some unknown unknownswill always remain unknown, as mysterians do, is not modesty its arrogance.

Maarten Boudry is a postdoctoral researcher of the philosophy of science at Ghent University. This article first appeared on The Conversation

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Has human evolution reached its peak for cognitive understanding? - The Independent

New Quantum-Mechanical Dissipation Mechanism Observed for the First Time – SciTechDaily

The gold tip is moved across the surface of the topological insulator and experiences energy loss only at discrete, quantized energies. This is related to the image potential states that are formed over the conducting surface of the topological insulator. Credit: University of Basel, Departement of Physics

Topological insulators are innovative materials that conduct electricity on the surface, but act as insulators on the inside. Physicists at the University of Basel and the Istanbul Technical University have begun investigating how they react to friction. Their experiment shows that the heat generated through friction is significantly lower than in conventional materials. This is due to a new quantum mechanism, the researchers report in the scientific journal Nature Materials.

Thanks to their unique electrical properties, topological insulators promise many innovations in the electronics and computer industries, as well as in the development of quantum computers. The thin surface layer can conduct electricity almost without resistance, resulting in less heat than traditional materials. This makes them of particular interest for electronic components.

Our measurements clearly show that at certain voltages there is virtually no heat generation caused by electronic friction. Dr. Dilek Yildiz

Furthermore, in topological insulators, the electronic friction i.e. the electron-mediated conversion of electrical energy into heat can be reduced and controlled. Researchers of the University of Basel, the Swiss Nanoscience Institute (SNI) and the Istanbul Technical University have now been able to experimentally verify and demonstrate exactly how the transition from energy to heat through friction behaves a process known as dissipation.

The team headed by Professor Ernst Meyer at the Department of Physics of the University of Basel investigated the effects of friction on the surface of a bismuth telluride topological insulator. The scientists used an atomic force microscope in pendulum mode. Here, the conductive microscope tip made of gold oscillates back and forth just above the two-dimensional surface of the topological insulator. When a voltage is applied to the microscope tip, the movement of the pendulum induces a small electrical current on the surface.

In conventional materials, some of this electrical energy is converted into heat through friction. The result on the conductive surface of the topological insulator looks very different: the loss of energy through the conversion to heat is significantly reduced.

Our measurements clearly show that at certain voltages there is virtually no heat generation caused by electronic friction, explains Dr. Dilek Yildiz, who carried out this work within the SNI Ph.D. School.

The researchers were also able to observe for the first time a new quantum-mechanical dissipation mechanism that occurs only at certain voltages. Under these conditions, the electrons migrate from the tip through an intermediate state into the material similar to the tunneling effect in scanning tunneling microscopes. By regulating the voltage, the scientists were able to influence the dissipation. These measurements confirm the great potential of topological insulators, since electronic friction can be controlled in a targeted manner, adds Meyer.

Reference: Mechanical dissipation via image potential states on a topological insulator surface by D. Yildiz, M. Kisiel, U. Gysin, O. Grl and E. Meyer, 14 October 2019, Nature Materials.DOI: 10.1038/s41563-019-0492-3

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New Quantum-Mechanical Dissipation Mechanism Observed for the First Time - SciTechDaily

Physicists have found quasiparticles that mimic hypothetical dark matter axions – Science News

An elusive hypothetical particle comesin imitation form.

Lurking within a solid crystal is aphenomenon that is mathematically similar to proposed subatomic particlescalled axions, physicist JohannesGooth and colleagues report online October 7 in Nature.

If axions exist as fundamentalparticles, they could constitute a hidden form of matter in the cosmos, darkmatter. Scientists know dark matter exists thanks to its gravitational pull,but they have yet to identify what it is. Axions are one possibility, but no one has found the particles yet (SN: 4/9/18).

Enter the imitators. The axions analogswithin the crystal are a type of quasiparticle, a disturbance in a material thatcan mimic fundamental particles like axions. Quasiparticles result from thecoordinated jostling of electrons within a solid material. Its a bit like how birdsin a flock seem to take on new forms by syncing up their movements.

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Axions were first proposed in thecontext of quantum chromodynamics the theory that explains the behaviors of quarks,tiny particles that are contained, for example, inside protons. Axions andtheir new doppelgngers are mathematically similar but physically totallyunrelated, says theoretical physicist Helen Quinn of SLAC National AcceleratorLaboratory in Menlo Park, Calif., one of the scientists who formulated thetheory behind axions. That means scientists are no closer to solving their darkmatter woes.

Still, the new study reveals for thefirst time that the phenomenon has a life beyond mere equations, inquasiparticle form. Its actually amazing, says Gooth, of the Max Planck Institutefor Chemical Physics of Solids in Dresden, Germany. The idea of axions is avery mathematical concept, in a sense, but it still exists in reality.

In the new study, the researchersstarted with a material that hosts a type of quasiparticle known as a Weyl fermion,which behaves as if massless (SN: 7/16/15).When the material is cooled, Weyl fermions become locked into place, forming acrystal. That results in the density of electrons varying in a regular patternacross the material, like a stationary wave of electric charge, with peaks inthe wave corresponding to more electrons and dips corresponding to fewerelectrons.

Applying parallel electric and magneticfields to the crystal caused the wave to slosh back and forth. That sloshing isthe mathematical equivalent of an axion, the researchers say.

To confirm that the sloshing wasoccurring, the team measured the electric current through the crystal. Thatcurrent grew quickly as the researchers ramped up the electric fields strength,in a way that is a fingerprint of axion quasiparticles.

If the scientists changed the directionof the magnetic field so that it no longer aligned with the electric field, theenhanced growth of the electric current was lost, indicating that the axionquasiparticles went away. This material behaves exactly as you would expect,Gooth says.

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Physicists have found quasiparticles that mimic hypothetical dark matter axions - Science News

The Power of Wrong Answers in Science Education – WIRED

No one ever said science education was easy. Certainly the concepts we teach, like conservation of momentum or quantum mechanics, can be hard to grasp. But what really complicates the endeavor is that were also trying to teach a deeper lesson at the same timeto help students understand the nature of science itself.

All too often, young people get the impression that science is about learning certain laws and then applying them to different situations. After all, thats what we make them do on tests, to show that theyve been doing the work. But thats not it at all. Science is the process of building these concepts through the collection of experimental evidence.

And while Im on it, lets call these concepts what they really arenot laws, but models. Science is all about building and testing models. It's difficult to help students understand that aspect of science when we just give them the models to begin with. Sure, in physics we often include historical or mathematical evidence to support big ideas, but that often isnt enough.

Of course, we cant start from scratch. If students had to build their own models from the ground up, it would be like trying to learn programming by inventing computers. As Isaac Newton is supposed to have said, we stand on the shoulders of giants. We must take models built by others and go from there.

But theres still another challenge in science education that is less often recognized: Students often enter a course with their own unarticulated ideas about how the world works. We call these misconceptions, but its important to realize that these are also models, based on their life experiences, and that they must make sense to the student.

What Id like to suggest is that this actually provides a great way into the adventure of science and an opportunity to meet our objectives as educators. If you can create a situation that challenges students assumptions and produces conceptual conflict, that's a great opportunity for learning.

Heres a fun example that Ive used, on the topic of light rays. I set up a point light source and put a piece of cardboard in front of it. Theres a small pinhole in the cardboard and a white screen behind. What do you expect to see?

No surprise: A light shining through a pinhole makes a dot on the screen. Now Ill ask the students: What if I have TWO light sources with the same single hole?

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The Power of Wrong Answers in Science Education - WIRED

China’s Silicon Valley aims to become the country’s top research center – Abacus

Shenzhen, home to Chinese tech giants Tencent, Huawei and DJI, is known for warp speed when it comes to new product development whether that be in mobile games, 5G wireless technology, or consumer electronics.

Now the Chinese government wants the southern metropolis, designated the countrys first special economic zone 40 years ago when it was a sleepy fishing village, to focus on the longer term by giving it an added role: fundamental research and development.

Often called Chinas Silicon Valley, the city of 12 million has been named as the location of the countrys fourth major national science center amid the Chinese governments ambitions to become a global technology and innovation powerhouse.

China is very good at the hardware, but basic research is not a simple task, said Jonathan Chee, project director at the Center for Entrepreneurship of the Chinese University of Hong Kong. The most cutting-edge research and technology are in the universities and its not easy to bring the talent together to form a cluster Im worried that the efforts would be too costly.

The science centers, managed by the Chinese Ministry of Science and Technology and the National Development and Reform Commission, include technology parks and government-funded laboratories tasked with undertaking basic research in fields such as nuclear reactions, quantum physics and astrophysics. The three existing science centers are in Beijing to the north, Shanghai on the east coast, and Hefei in central China.

Shenzhen is very innovative in technology applications, but the city is traditionally weak in basic science research, said Guo Wanda, executive vice-president of the Shenzhen-based think tank China Development Institute. Without breakthroughs in technologies, the city will be one step behind other international cities.

Details of the Shenzhen project were unveiled by Chinese authorities in August as government planners looked to major mainland cities to drive regional development amid Chinas ongoing trade and tech war with the US.

Chinese President Xi Jinping has repeatedly called for industry to innovate and become more self-reliant. Self-determination and innovation is the unavoidable path to climb to the worlds top as a leading player in technology, Xi told a group of Chinese scientists last year. We [should] hold innovative development tightly in our own hands. [We have to] put much effort in key areas where we are facing bottlenecks and make breakthroughs as soon as we can.

As a key plank in Chinas many policies to advance basic research, the national science centers are designed to serve the strategic needs of the nation by bringing together high level talent and offering an open research environment, according to the countrys 13th five-year plan.

Large-scale technology infrastructure and national labs are expected to be built in Shenzhen, especially in the fields of biological science, cyberspace and materials science, said Guo.

Shenzhen already has Chinas first national gene bank and has hosted a national supercomputing center, though the city still ranks well behind Beijing and Shanghai when it comes to government support in basic science, with 90 per cent of the research institutions in the city funded by private enterprises.

For basic science research, it is necessary to have central government support it is a national strategy and needs nationwide effort no matter whether in the US or Japan, said Liu Ruopeng, head of the Shenzhen-based Kuang-Chi Institute of Advanced Technology,a not-for-profit research institute backed by Kuang Chi Group.

Silicon Valley owes its start in large part to Stanford University in Palo Alto, Japans Tsukuba Science City is home to the STEM-focused University of Tsukuba, while Taiwans Hsinchu Science Park has drawn engineering graduates from nearby National Chiao Tung University and National Tsing Hua University.

However, Shenzhen is not known for its institutions of higher education. Shenzhen University, located in the citys Nanshan district, was placed in the 601st to 800th group in terms of global ranking, according to The Times Higher Education World University Rankings.

Beijing, in contrast, boasts two of the countrys top universities, Peking University and Tsinghua, which rank among the top 50 internationally. As of this year, the Chinese capital had also established a cluster of around 90 universities. Elsewhere, Shanghais Fudan University and Shanghai Jiao Tong University and Hefeis University of Science and Technology are all ranked among Chinas top 10 universities.

Shenzhens status as a science center is expected to encourage overseas universities to set up graduate schools and research institutes in the city. The University of Cambridge in the UK and Peking University are in talks about hosting joint programs in Shenzhen while the Shenzhen MSU-BIT University was jointly established by Lomonosov Moscow State University and the Beijing Institute of Technology.

Shenzhen beat more than a dozen rivals including Chengdu in the southwest and the central Chinese cities of Xian and Wuhan, to secure the countrys fourth science center. Industry experts point to a few advantages that enabled Shenzhen to win amid the fierce competition. One was its role as the technology driver in the Greater Bay Area, a central government plan to turn 11 cities in southern China into an international innovation and technology hub to compete globally.

Another advantage was geography. The three current centers are located in north, east and central China respectively. The new center in Shenzhen will help balance the output of national innovation and drive economy transformation in southern China, said Liu.

It is not hard to understand why Chinese cities vie so keenly for such designations.Like in Silicon Valley, Tsukuba and Hsinchu, government support combined with top level universities attract the talent and capital needed to succeed. Shenzhen, too, expects to see new labs, institutions and universities with its new-found national science status, say experts.

The Shanghai Science Center has received funding of 13.8 billion yuan (US$2 billion) from the central government for multiple large-scale scientific facilities, according to a recent report from state media Xinhua. By 2020, the Chinese government plans to invest 30 billion yuan in the three key centers.

By 2018, China had announced 38 large-scale scientific facilities in areas such as physics and astronomy 22 operating and the remainder planned but none are in southern China. Most are co-located within the existing three national science centers.

Shanghai was chosen to host the countrys first national science center in 2016, supported by infrastructure to enable life science, supercomputing and photon research for applications in integrated circuits, artificial intelligence and bio medicine. The second national science center in Hefei is focused on information technology, energy, health and the environment, and will conduct research in areas such as quantum communications, nuclear fusion, smog prevention and cancer treatment.

The nations third facility, to be operating in the capital of Beijing by 2020, will focus on physical science, space science and geoscience.

Shenzhens designation as a national science center may be new but the citys planners have had their eyes on the prize for a while. In January 2018, the city government proposed a national science and technology center and laid out an ambitious proposal called Ten Plans that entailed 10 scientific and technology infrastructure projects, 10 overseas innovation centers and 10 manufacturing innovation centers.

There is even a plan to establish 10 laboratories backed by Nobel Prize-winning scientists, with blue LED inventor and 2014 Nobel laureate in physics Shuji Nakamura and 2005 laureate in chemistry Robert Grubbs already signed up.

We cannot expect to make a profit from basic science research as quick as technology applications, said Guo. We have to keep investing and be patient.

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China's Silicon Valley aims to become the country's top research center - Abacus

A Scientific Explainer of What Terrence Howard Was Talking About at the Emmys – VICE

In a year of big statements on the Emmys red carpet, from Viola Davis sneakers-and-gown combo to impassioned speeches on transgender rights and equal pay, one managed to stand out at last week's awards show: Empire star Terrence Howards deep dive into geometry, ancient philosophy, and quantum physics.

"Ive made some discoveries in my own personal life with the science that, yknow, Pythagoras was searching for, he told a very confused interviewer. I was able to open up the flower of life properly and find the real wave conjugations weve been looking for for 10,000 years.

It could have ended there, but then, Howard got down to the science:

All energy in the universe is expressed in motion, all motion is expressed in waves, all waves are curves, so where does the straight lines come from to make the Platonic solids? There are no straight lines. So when I took the flower of life and opened it properly, I found whole new wave conjugations that expose the in-between spaces. Its the thing that holds us all together.

Howard's mind-boggling answer to a casual interview question about quitting acting after Empire ends was notable enough that the clip went viral on Twitter last week.

Theres a lot to unpack here, but most surprising of all is that it's partly based on real science. When it comes to straight lines, hes not wrong.

There are no straight lines, actually

Its true that there are no straight lines in the physical world that we see and experience around us, but this has very little to do with wave-curvature or Howards (false) claim that all energy is expressed in motion. Instead, its a quirk of maths and logic due to how we define "straight" and how we define "line."

Strictly speaking, any line (straight or curved) has a thickness of zerothats just what we mean in mathematical terms when we refer to a line. If a "straight" line with a finite length has any thickness at all, it is actually an extremely thin rectangle, not a line.

It should be obvious then that no true lines exist physically; even the thinnest line we can draw has a width greater than zero. Straight lines are an idealised mathematical concept, and so arguably don't "exist."

So we can prove Howards claim without even touching on whether real-world objects with straight lines exist. As it turns out, hes onto something here, too.

Take any physical object with lines that look perfectly straight. The closer we look, the more we see imperfections or inconsistencies in materials which reveal that there are tiny deviations from perfect straightness.

Even light doesnt really travel in straight lines. At the smallest physical scale, quantum physics jumps into action, which means things get really weird. At the quantum level, theres more to light than meets the eye, since it is made up of light particles (photons) which sometimes behave like one continuous wave, and sometimes like individual particles.

If we couldnt break down light into photons, then it could be said to move in perfectly straight lines. But photons have the strange property of not having trajectories we can calculate; they simply show up at an end point when we go to measure them.

All energy is motion, and all motion is a wave

At this point, it might be wise for Howard not to pursue a potential post- Empire career as a science professor.

Motion is one type of energy (called kinetic energy), but its certainly not the only fundamental type of energy. All forms of energy can be classed into one of two overall types: kinetic (motion) or potential, which is the energy stored when forces act on an object which would cause motion in the right conditions, like stored electrical energy.

Within the two broad types of energy, other forms include electrical energy, thermal energy, radiation, nuclear energy, and others.

Its also not true that all motion is a wave. In fact, I suspect Howard meant to put this entire statement in reverse: "All motion is energy, and all energy is a wave." This is closer to the truth, but still misses the mark.

Due to quantum physics, everything behaves in weird, form-changing ways when you get down to an infinitesimally small level. Stationary particles with mass convert some of their mass into energy in order to have motion (energy-mass equivalence) and energetic particles behave like waves with frequency, and vice versa (wave-particle duality).

Quantum physics reveals that properties of particles (mass, energy, motion, momentum, location, etc.) are interchangeable with properties of waves (frequency, wavelength), but it doesnt tell us that everything is made up of curved waves. In fact, quantum physics prevents us from making definitive statements like this.

What are Platonic solids and the flower of life?

Howard probably didnt come up with these theories himself. Hes clearly into "sacred geometry," a new-age spiritual practice that runs with the ideas of ancient philosophers and mathematicians like Plato, Euclid and Pythagoras.

Platonic solids are a set of five 3D shapes where all the faces are uniformly shaped and sized, all edges and angles are regular, and each corner of the object has the same number of faces meeting at that point. Examples of Platonic solids are cubes and tetrahedrons.

Sacred geometry assigns new meaning to geometrical objects like these and more complex shapes like the "flower of life,"a geometric pattern which contains all five Platonic solids within itusing them to connect with different energies.

Today this idea seems like pseudo-science at best, but long after Plato and his contemporaries came and went, "real scientists continued to obsess over how to relate geometry to the physical or natural world.

Take the important 17th century physicist Johannes Kepler, who tried (and failed) to use Platonic solids to model the solar system. Even though he abandoned the geometrical side of his work, his original theories eventually gave rise to revolutionary theories of planetary orbits, which are still used to describe movement of planets today.

So, in some respects Howard is actually in good company. But I still wouldnt recommend following his lead and using outdated ideas about obscure shapes to guide your important life decisions.

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A Scientific Explainer of What Terrence Howard Was Talking About at the Emmys - VICE

Precision physics with ‘tabletop’ experiments – Stanford University News

The history of particle accelerators is one of seemingly constant one-upmanship. Ever since the 1920s, the machines which spur charged particles to near light speeds before crashing them together have grown ever larger, more complex and more powerful.

Consider: When the 2-mile-long linear accelerator at SLAC National Accelerator Laboratory opened for business in 1966, it could boost electrons to energies of about 19 gigaelectronvolts. The Large Hadron Collider (LHC) at CERN, which finished construction in 2008, can boost protons to more than 700 times higher energy levels and resides in a massive elliptical tunnel wide enough to encircle a small town. Future supercolliders being planned by CERN, China and Japan promise to be even more immense and energetic (and also more expensive).

The strategy has paid off handsomely with discoveries that have helped confirm the soundness of the Standard Model, our current best understanding of how natures fundamental forces and subatomic matter interact.

As successful as particle accelerators have been, however, Stanford theorists Savas Dimopoulos and Peter Graham are betting that scientific treasures await discovery in the other direction as well. For years, the pair have argued that smaller and less expensive, but more sensitive, instruments could help answer stubborn mysteries in physics that have resisted the efforts of even the largest atom smashers questions like What is dark matter? and Do extra spatial dimensions exist?

Peter and I and our group have been thinking about this for 15 years, said Dimopoulos, who is the Hamamoto Family Professor at Stanfords School of Humanities and Sciences. We were sort of lonely but very happy because we were exploring new territory all the time and it was a lot of fun. We felt like eternal graduate students.

Peter Graham and Savas Dimopoulos are among Stanford physicists working on smaller-scale devices to answer large questions. (Image credit: L.A. Cicero)

But their ideas have been slowly gaining traction among physicists, and last fall the Gordon and Betty Moore Foundation awarded Stanford and SLAC researchers three grants totaling roughly $15 million to use quantum technologies to explore new fundamental physics. Key to these efforts are the kinds of small-scale, tabletop experiments (so-called because most of them would fit on a lab bench or in a modest-sized room) that Dimopoulos and Graham have long advocated for. Everything is smaller, except for the ideas, Dimopoulos quipped. These types of experiments could help solve some very important problems in physics.

The instruments Dimopoulos and Graham have in mind exploit the weird properties of quantum mechanics such as wave-particle duality and the seemingly telepathic link between entangled particles to detect and measure minute signals and effects that particle accelerators are simply not attuned to.

Tabletop experiments are considered high-risk, high-reward projects because they are generally cheaper to build and operate than colliders, said Asimina Arvanitaki, a theoretical physicist at the Perimeter Institute. If youre pitching a project that costs several billion dollars, you better have a very good reason for its existence and be reasonably sure youre going to succeed, added Arvanitaki, a former Stanford postdoc in Dimopoulos lab. But the cost of tabletop experiments is so low, and the timescales for producing results is so short, that it takes some of that pressure off.

The Moore Foundation grants will fund three projects: Two are experimental and will focus on developing new technologies for detecting dark matter and measuring gravitational waves. But the third, worth about $2.5 million and awarded to Dimopoulos and Graham, will be used to further develop the theoretical underpinnings that will enable future experiments.

Theres been a history of particle accelerators discovering new physics and finding new particles, but its not clear that that can go on forever, so its important to think of other complementary ways to get at these underlying questions about nature, said Ernie Glover, the Moore Foundations science program officer.

Everything is smaller, except for the ideas. These types of experiments could help solve some very important problems in physics.

Savas Dimopoulos

Professor of Physics

Crucially, the experiments Dimopoulos and Graham are proposing rely on relatively mature, high-precision technologies that, for the most part, were developed with other uses in mind and for other fields, such as medicine and applied physics. Thats what got us really excited, Dimopoulos said. We realized there were all these possibilities out there that particle theorists werent really thinking about.

A good example is nuclear magnetic resonance, or NMR, imaging, which forms the basis of magnetic resonance imaging, or MRI, a common medical scanning technique.

A few years ago, Graham and others theorized that a proposed ultralightweight dark matter candidate called an axion could influence the nuclear spin of normal matter. Dark matter is thought to make up the bulk of the matter in the universe, but it has evaded every attempt so far at characterization. Excited, Graham contacted an atomic physicist at the University of California, Berkeley, named Dmitry Budker to discuss designing a dark matter detector based on this effect only to discover that the technology already exists.

He said its going to work because what we were describing was basically NMR, said Graham, a theoretical physicist at the Stanford Institute for Theoretical Physics.

Graham and Budker teamed up with other physicists to design the Cosmic Axion Spin Precession Experiment, or CASPEr, which uses NMR (nuclear magnetic resonance) to detect axion and axion-like particles. These particles are predicted to have such weak interactions and low masses that they would never show up in a collider, which are better equipped to search for massive dark matter candidates such as WIMPs (weakly interacting massive particles).

Former Stanford postdoc Asimina Arvanitaki, now at the Perimeter Institute, has proposed several tabletop experiments to investigate physics beyond the reach of particle colliders. (Image credit: Colin Hunter)

Similarly, another Moore Foundation-funded tabletop experiment called MAGIS-100 relies on atom interferometry technology initially developed in the 1990s as a general-purpose tool for making precise measurements. The project, a collaboration between Stanfords Mark Kasevich and Jason Hogan and researchers at Fermilab and other universities, could potentially detect ripples in spacetime known as gravitational waves around 1 hertz, a frequency range beyond the sensitivity of most existing or even proposed detectors.

Current gravitational wave detectors like LIGO are sensitive to the very final moments of the black hole collisions that generate the spacetime ripples, but MAGIS-100 could provide scientists with a much longer viewing window.

LIGO saw just a fraction of a second of the event, but the black holes were twirling around each other and generating gravitational waves for millions or billions of years before that. Those waves were just in lower frequency bands, Graham said. By looking at other frequencies, we could observe the black holes for longer and perhaps discover new gravitational wave sources.

Dimopoulos and Graham plan to use the Moore Foundation-funding to continue devising new schemes for co-opting technologies like NMR and atom interferometry in the service of fundamental physics research.

Its that connection thats hard, Graham said. The experimental physicists and engineers who develop the technologies arent necessarily thinking about what other deep, fundamental questions could be tested, and the theorists are often unaware that tools for testing their ideas already exist.

But Dimopoulos and Graham are now old hands at making such connections. In principle, you have to know all possible technologies, Graham said. In practice, you just have to know the right ones, but it takes a nontrivial intuition to realize something like Oh, wait a minute, it looks like this technique might actually be able to observe extra dimensions or some other new physics.

In one sense, what Dimopoulos and Graham are advocating for is a return to the way physics was done before colliders came to play such an important role in physics and the division of physicists into primarily theoretical and experimental camps.

Before World War II, physics was just like what were doing right now, Dimopoulos said. Felix Bloch was both a theorist and an experimentalist, and so was Enrico Fermi. Even Einstein did experiments. There wasnt a ready group of experimentalists that you could outsource your ideas to. You had to invent the techniques and look around at emerging technologies.

To read all stories about Stanford science, subscribe to the biweeklyStanford Science Digest.

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Precision physics with 'tabletop' experiments - Stanford University News

Andrea Young uncovers the strange physics of 2-D materials – Science News

Speaking with Andrea Young feels likewatching a racehorse holding itself back at the starting gate. We met on thecampus of the University of California, Santa Barbara, where hes a condensedmatter physicist, to chat about his work on 2-D materials. His mind seems to beworking faster than the conversation can flow. My sense is, once the reins areloosened and hes back in the lab hell take off.

Youngs colleagues confirm thats thecase. Hes a whirlwind, says physicist Raymond Ashoori of MIT. When Young wasa postdoc in his lab, Ashoori says, it felt like an idea a minute.

Young, 35, has a way with substances shaved to the thickness of a single atom, such as the sheets of carbon known as graphene. His research has revealed new states of matter, and advanced scientists understanding of the strange physics that arises when materials are sliced thin.

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Things change a lot when you change thenumber of dimensions, Young says.

As a graduate student at ColumbiaUniversity, Young helped create a new type of material that transformed howscientists study graphene. Along with physicists Cory Dean, Philip Kim andcolleagues, Young devised a technique for layering graphene with othermaterials, in particular another compound that forms 2-D sheets called hexagonalboron nitride. The combination makes the sometimes-finicky graphene easier towork with. And the materials electrons can be coaxed to behave in unusual ways,interacting strongly with one another, for example. Reported in Nature Nanotechnology in 2010, the technique was quickly adopted byscientists around the world. Everybody uses it now, Ashoori says.

After his time at Columbia, Young went on to stints at MIT and the Weizmann Institute of Science in Rehovot, Israel, before landing at UC Santa Barbara in 2015. So far, Young has used his layering technique to reveal new quantum phenomena and states of matter with tongue-twisting names like Hofstadters butterfly and fractional Chern insulators. In many of the materials Young studies, electrons exhibit collective behavior, resulting in quasiparticles, excitations in a material that mimic a real subatomic particle. Its a bit like how a crowd of individual people can do the wave by working together.

Keeping up with Youngs rapid progress inthe lab kept his graduate adviser, Kim, busy. Hes extremely brilliant andvery energetic, says Kim, now at Harvard University. Youngs understanding oftheoretical concepts, in combination with experimental know-how, makes himquick to generate and implement new ideas, or follow up on hot research topics.In 2018, he, Dean and colleagues were the first to replicate a blockbusterresult in condensed matter physics: Two sheets of graphene, when layered androtated with respect to one another, become superconducting, allowing electrons to flow without resistance. Youngand colleagues added their own twist, reporting in the March 8 Science that the materialssuperconductivity could be tuned by putting it under pressure.

Youngs swiftness seems to take multipleforms quickness of thought, experimental agility and even fleetness of foot.During a particularly frenzied time, Dean, who has collaborated with Young foryears, was headed to the lab bright and early at around 7 a.m. When Dean lookedup, 100 yards ahead of me was Andrea, rushing even faster to get to the lab.

Youngs fascination with physics came onquickly, too: From my earliest memories, I wanted to be a physicist, and itsnot clear where that idea got nucleated, says Young, who grew up inWashington, D.C.

He doesnt see himself as fast, though. Ratherthan aiming for quick developments, he says that hes motivated by big-picture,long-term questions. His current passion is searching for a proposed new classof quasiparticles, called non-abelian anyons. Thats become the thing that Im obsessed with, he says.

Scientists have discovered a widevariety of quasiparticles, but anyons dont fit into either of the twocategories all other particles do. They arent fermions, familiar particleslike electrons, protons and neutrons; nor are they bosons, which include force-carryingparticles, such as photons, particles of light that transmit electromagneticforces.

Anyons, which appear only in twodimensions, are misfits. And non-abelian anyons are stranger still. Theorysuggests they can be braided with one another by swapping their locations ina material. That braiding could protect fragile quantum information frombecoming corrupt, potentially allowing scientists to create quantum computersthat can perform calculations no standard computer can.

But no one has definitively shown thatnon-abelian anyons exist and have the useful properties necessary for quantumcomputing. A new state of matter called a fractional Chern insulator, which Young and colleagues reported for the firsttime in 2018 in Science, could be alikely hiding place. Young hunter of strange denizens of 2-D matter is inpursuit.

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Andrea Young uncovers the strange physics of 2-D materials - Science News

Princeton announces initiative to propel innovations in quantum science and technology – Quantaneo, the Quantum Computing Source

The new initiative builds on Princetons world-renowned expertise in quantum science, the area of physics that describes behaviors at the scale of atoms and electrons. Quantum technologies have the potential to revolutionize areas ranging from secure data transmission to biomedical research, to the discovery of new materials.

The inaugural director will be Andrew Houck, professor of electrical engineering and a pioneer in quantum computing technologies. The initiative will bring together over 30 faculty members from departments across campus in the sciences and engineering.

This initiative enables the work of our extraordinary quantum faculty and their teams to grow research capabilities and attract talented minds at all levels to Princeton, so that they can discover new materials, design new algorithms, and explore the depths of the underlying science in an exciting environment of discovery and innovation, said Dean for Research Pablo Debenedetti, the Class of 1950 Professor in Engineering and Applied Science and professor of chemical and biological engineering.

The potential benefits to society from quantum information science make this an essential endeavor for Princeton. The initiative will provide tremendous opportunities for Princeton students and postdoctoral researchers to make profound contributions to future technologies, said Deborah Prentice, University provost and the Alexander Stewart 1886 Professor of Psychology and Public Affairs.

The initiative comes at a time of national momentum for quantum sciences at the University, government and industry level. In 2018, the federal government established the National Quantum Initiative to energize research and training in quantum information science and technology. New technologies over the past decade have enabled companies including Google, IBM and others to build research-stage quantum computers.

The Princeton Quantum Initiative will enable new collaborations both across campus and with other universities and industry. Within the University, the initiative will include faculty in the departments of electrical engineering, physics, chemistry, computer science and mechanical and aerospace engineering.

Princeton has world leaders at all layers of this technology, including foundational science, materials synthesis and characterization, quantum device platforms, computer architecture, algorithm design and computational complexity, said Houck. We have an incredible collection of experts in their respective disciplines, and the Princeton Quantum Initiative gives us an entity which brings everyone together to accelerate the pace of discovery.

To support the future of quantum research, the initiative will train a new generation of quantum scientists and engineers through financial support for graduate students and postdoctoral researchers. Annually, Princeton will award two prestigious graduate student fellowships, each providing support for three years, as well as two postdoctoral fellowships for three-year terms, with fellows able to choose projects and faculty mentors.

For undergraduates, the initiative will build on Princetons leadership in the development of courses whose target audience includes those with no prior quantum physics background. The initiative will help coordinate teaching efforts across departments, offer more cohesive and wide-ranging instruction in quantum science and engineering, and provide undergraduates with opportunities to work on faculty-led projects.

The research supported through the initiative will span areas from new materials science for quantum devices to quantum computer architecture, algorithm design and computational complexity.

Quantum science promises to deliver dramatic enhancements in information processing and communications. Computers built on quantum principles can solve problems that are impossible with todays machines, potentially leading to discoveries in fields such as chemistry, materials science, optimization and information security.

Sensors based on quantum approaches can probe materials and biological systems at the nanoscale with unprecedented precision and resolution. Such sensors could detect medical conditions or be used for quality control in manufacturing of sensitive electronic equipment.

Quantum communication systems can provide provably secure communication that cannot be hacked without detection. Quantum encryption could someday replace todays internet security algorithms to ensure privacy of data transmissions.

Princeton has a long history of contributing foundational discoveries in quantum science. Over the decades, Princeton researchers have made major contributions to quantum theory and trained graduate students that have become leading quantum scientists and technologists. More on the research expertise of Princetons quantum scientists and engineers is available online.

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Princeton announces initiative to propel innovations in quantum science and technology - Quantaneo, the Quantum Computing Source

Is It a Wave or a Particle? It’s Both, Sort Of. – Space.com

Paul M. Sutter is an astrophysicist at The Ohio State University, host of Ask a Spaceman and Space Radio, and author of "Your Place in the Universe." Sutter contributed this article to Space.com's Expert Voices: Op-Ed & Insights.

Is it a wave, or is it a particle? This seems like a very simple question. Waves are very distinct phenomena in our universe, as are particles. And we have different sets of mathematics to describe each of them. So, if we want to go about describing the entire universe, this appears to be a very handy classification scheme except when it isn't. And it isn't in one of the most important aspects of our universe: the subatomic world.

When it comes to things like photons and electrons, the answer to the question "Do they behave like waves or particles?" is yes.

Related: Antimatter Is Both a Particle and a Wave, New Experiment Confirms

At first glance (and even at deeper glances), waves and particles are very different. A particle is, as best as I can put it, a thing. It's a small, single, finite object. You can hold a particle in your hand. You can throw a particle at someone else and watch it bounce off of them. It's localized. You can point to a particle and say, "Look, the particle is right there, exactly where I'm pointing."

Particles have momentum and positions.Particles will move in straight lines until something changes their direction.Particles can bounce off of other particles, and they can change trajectories. Think of bullets or speeding cars. Theyre not literally small, subatomic particles, but they act like particles when they hit other things.. Many physical interactions can be described simply as particles bouncing off of one another.

On the other hand, waves are almost completely different. They're not localized. If you want to indicate where a wave is, you have to move your hands around vaguely gesturing, saying, "It's all over there." You can't hold the wave in your hand. Instead, the wave passes over, around or even through your hand.

This animation shows what happens when two waves (shown in green and blue) interfere.

(Image credit: Wolfgang Christian/Francisco Esquembre/Francisco Esquembre, CC BY-SA 4.0)

Waves are oscillations, meaning they wiggle. They transport energy from one place to another. Waves don't really bounce off of, but instead interfere with, one another. Sometimes, when the waves come together just right, crest meet crests, and you get double waves. This is called "constructive interference." But sometimes, the waves cancel each other out, and you get nothing at all an interaction known as "destructive interference." Waves can turn corners, and when they pass through narrow openings, they can fan out, or diffract. There are many types of waves in our universe, like ocean waves and waves on a Slinky.

Both waves and particles are described by very, very different sets of mathematical equations. So, if you want to describe something scientifically, first you have to decide if it's a wave or a particle; then you can pull out the correct mathematical tools to make predictions about how it will behave and act. And for a couple hundred years, this line of thinking was a fine approach to solving all the physics problems in the world.

The problems with this approach started with light itself. In the early 1800s, the English scientist Thomas Young played some games with light by shining some beams through two narrow openings onto a screen behind them. What he found was a classic interference pattern with stripes of varying intensity on the screen. This is exactly what water waves would do when passing through two narrow channels. Some of the light waves would add together, and some of the waves would cancel out, leaving a striped pattern on the back screen. This is pretty solid evidence that light acts like a wave, because this is exactly what waves do.

This idea was bolstered a few decades later when Scottish physicist James Clerk Maxwell figured out that electricity and magnetism were actually two sides of the same electromagnetic coin and, in the process, realized that light is waves of electricity and magnetism. That gave a conclusive picture as to what's doing the waving when it comes to light: its electricity and magnetism. Light is a wave. Book it, done.

Then, in the late 1800s, German theoretical physicist Max Planck threw a monkey wrench into everything when he studied blackbody radiation. To explain his observations, he proposed that light can be emitted only in discrete little chunks. A few years later, Albert Einstein threw his weight into the matter by studying the photoelectric effect, and proposed that not only is light emitted in little chunks, but light itself is made of little packets of energy called photons. In other words, light was behaving as a particle in these experiments.

So, different kinds of physics experiments were revealing different kinds of properties of light. Sometimes, light acted like a wave, and sometimes, light acted like a particle. Which was it? The answer is that it's both. And it gets even worse.

In the 1920s, a young physicist named Louis de Broglie made a radical suggestion: Since light has energy, momentum and a wavelength, and matter has energy and momentum, maybe matter has a wavelength, too. That's something that's easy to say but hard to wrap your head around. What does it mean for matter to have a wavelength? Or was de Broglie just horribly mistaken?

It turns out that de Broglie nailed it. At first blush, you may wonder how electrons could be anything but particles, because you can literally hold them in your hand, and they do a lot of bouncing. When you shoot electrons through two slits, you end up with the exact same interference pattern that you do with lights: alternating vertical stripes of more and fewer electrons.

A famous 1800s physics experiment, the double-slit experiment, revealed that light behaves like both particles and waves.

(Image credit: Jordgette/Wikimedia Commons, CC BY-SA 3.0)

What's going on? Electrons are acting like waves when they don't look anything like waves. What's doing the waving?

The answer comes through quantum mechanics, and describing that answer involves interpreting some of the deep mathematics. The most common picture, called the Copenhagen interpretation, says that the wave that we associate with matter is a wave of probability representing all the possible places where a particle might be the next time we go looking for it. This range of probability is described by an equation that has the same mathematical bones as that of any other wave equation. In this picture, that's what's doing the waving: the possible places the particle could be.

So, as the electrons pass through the slits in de Broglie's experiment, they can't exactly decide where they want to be. Those waves of uncertainty crash into each other and interfere, merging and canceling each other out just like any other waves. Then, when an electron's wave hits the back screen, the particle finally has to decide where to land. Slowly, electron by electron, the wave pattern builds up.

Just like light, sometimes matter acts like a particle, and sometimes, it acts like a wave. So, are light and matter made of waves or particles? The answer is both, sort of.

Learn more by listening to the episode "Is everything a wave or a particle, and why does my head hurt?" on the Ask A Spaceman podcast, available oniTunesand on the web ataskaspaceman.com. Thanks to Rowan H., Ethan L., Broc P., Madhab D., Grisham J., Jeff G., Cortney H., Joshua Z., @shrenicshah, Mike D., Lynn R., A C, Rick S., Robert P., and @ShaunFosmark for the questions that led to this piece! Ask your own question on Twitter using #AskASpaceman or by following Paul @PaulMattSutter and facebook.com/PaulMattSutter.

Follow us on Twitter @Spacedotcom and onFacebook.

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Is It a Wave or a Particle? It's Both, Sort Of. - Space.com

Quantum-inspired Beckman Institute celebration will be anything but small – Central Illinois Buzz

Wednesday, Oct. 2 ,will be declared Beckman Institute Day by the mayors of Urbana, Champaign and Savoy, who, along with others at the University of Illinois Campus, will mark the science centers 30th anniversary in song, word and artistic visualization.

The Jupiter String Quartet of the College of Fine + Applied Arts will be giving an encore performance of Quantum Rhapsodies, originally presented in April, with narration by creator and physicist Smitha Vishveshwara on Wednesday at 6 pm The program, shown in the centers atrium, features visualizations of the quantum world and is a meditation on quantum physics and its role in our universe through live music, narration and visuals.

A reception will precede the performance and proclamation at 5:30 pm. The 30th anniversary celebration kicks off with Mayors Diane W. Marlin of Urbana and Deborah Frank Feinen of Champaign, along with Savoy Village President Joan Dykstra making the official proclamation at 5:50 pm in the atrium of the Beckman Institute of Advanced Science and Technology.

An informal Q&A session with the shows creators will follow at about 7 pm. The Beckman Institute is also hosting several other events in conjunction with its anniversary celebration, including a sold-out pop-up escape room.

On Oct. 3 at 4 pm, a talk from Columbia University Professor Yaakov Stern on how lifestyle, genetics and brain anatomy may affect age- or dementia-related brain changes, Cognitive Reserve: An Evolving Concept.

Following the lecture at 5:30 pm there will be light refreshments served in the atrium, where a few of Beckmans graduate students and postdoctoral researchers will share informal and compelling stories about their research. The students are currently attending a three-day workshop with NPR podcast host Sandra Tsing Loh.

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Quantum-inspired Beckman Institute celebration will be anything but small - Central Illinois Buzz

Our world is in need of the Mahatmas teachings: Dalai Lama – Livemint

For decades, the 14th Dalai Lama has said that kindness is the only religion, and that differences can be put aside if people see themselves as belonging to a larger world community. Gandhis words, as well as the teachings of Buddhist masters, have guided him, he says. While accepting the Nobel Peace Prize in Oslo in 1989, he said it was a tribute to the man who founded the modern tradition of non-violent action for change, Mahatma Gandhi, whose life taught and inspired me". To mark Gandhis 150th birth anniversary, the Dalai Lama spoke to Mint about the continuing relevance of Gandhi and the ideas of non-violence and kindness.

What is it about Mahatma Gandhi that continues to inspire you?

He was the most influential person of the 20th century with his idea of non-violence, ahimsa. He took a 3,000-year-old Indian tradition of ahimsa and karuna (compassion) and made it something living and relevant. He made it relevant by fighting for Indias freedom through non-violencethats great.

At that time, some people may have felt that Gandhis non-violence was a sign of weakness, but non-violence under difficult circumstances is a strength, not a weakness. As far as I know, Nelson Mandela totally followed Mahatma Gandhis way. As did Martin Luther King (Jr).

Personally, since childhood, we often heard about Mahatma Gandhi of India". On one occasion in a dream, I met Mahatma Gandhiji (chuckles). We didnt talk, just his face (appeared). In winter, I stayed in the Potala Palace, in summer in the Norbulingka Palace. So once, during winter in the Potala, in my dream, Mahatma Gandhiji appeared. Not like in the pictures but a real Gandhi (laughs).

What is the relevance of Gandhis ideas and non-violence today?

It is quite simple. Now, many scientists say basic human nature is compassionate because we are social animals. In ancient times, the community meant your own family and your own village; in the modern sense, community is the whole world. The world is the same human community. If you think of that, non-violence is very relevant. As individuals, our future and our prosperity depends on the world community, on all communities.

We Tibetans consider India our sacred neighbour because the Buddha dharma came from India. I jovially tell people, traditionally, for thousands of years we considered Indians our guru, and we were the chela (disciple), the very reliable chela. In the gurus own land, the Nalanda tradition has been seeing many ups and downs. During these periods, we, as the reliable chela, kept the Nalanda tradition intact.

Previously, you were the guru and we the chela; now I think its different (laughs). You have forgotten the Nalanda tradition, but weve kept it alive. Here in exile, we have our own organized community and have re-established all those historical monastic traditions in this country. So now, one of my commitments is to revive the ancient Indian knowledge of ahimsa and karuna, not through prayer but through training the mind and emotion.

Do you think Mahatma Gandhi was an influential guru or a humble chela?

First, he was a chela of Indias thousands-years-old tradition. Then, many millions of followers came along and they considered Mahatma Gandhi a guru

Do you think Gandhi was influential because he never thought of himself as a guru but as a chela?

Completely agree. Thats true. Frankly speaking, I also have many followers. I have always considered myself a simple Buddhist monk. The seven billion human beings in the world are the same mentally, emotionally and physically. This conviction brings a sense of oneness with seven billion beings. Some Lamas, including some Indian gurus, they feel they have something special (laughs).

I, too, face some danger of people praising me too much. Then, at that time, you must tell yourself, You are a humble follower of Buddha." Thats very important. If you yourself become a slave of destructive emotion, how can you teach other people?Dalai Lama

So do you think weakness is part of greatness?

This is quite a philosophical question (laughs). It is important to know your own weakness. Then you can improve. If some Tibetan and Hindu Lamas consider themselves great, it is important to test, to criticize, to tease them. If they still remain completely calm, that shows they truly practice or implement what they teach other people.

Today, how do people live in simplicity, with older traditions, without ego or anger, when there is so much inequality and distraction due to technology?

Modern education came from the West, introduced by the British. This system does not know how to tackle emotional problems through meditation. Modern education is oriented towards material wealth. So, when people face anger, hatred, fear or jealousy, they do not know how to tackle it. India must revive ancient knowledge through analytic meditation to reduce destructive emotion, and increase constructive emotion.

My latest commitment is to try to revive this ancient Indian knowledge in modern India. It is the only nation that can combine modern education, technology, science, these things that are very useful, with ancient Indian knowledge of how to bring peace of mind.

Was Gandhi a link between the ancient and modern?

Gandhiji totally dedicated himself to non-violence but I dont know how much he contributed to combine modern education and ancient Indian education about the mind. Gandhiji was a very practical person and educated in England. He was committed to ahimsa, but karuna (compassion), I dont know.

How do you make Mahatma Gandhi, 150 years after his birth, relevant today? The younger generation only sees him on Indian currency notes...

(chuckles) The world needs Mahatma Gandhijis teachings and practice of non-violence. Many problems in the world today are of our own creation. Whenever we see a problem, our first reaction is to ask how to tackle this by force. Thats totally wrong. Violence may be a sincere motivation, but the method is wrong. Violence is mutual destruction. In human history, the weapon has become very important. That is the outdated way. One nation cannot eliminate the rest of the nations who are not very friendly with it. Whether we like it or not, we have to live side by sidethats the reality.

A modern education is very much oriented towards material wealththats not adequate. How to tackle anger, fearthese are not religious matters, these are a question of health of the mind of the human being. Education should include education about peace of mind, not based on religious faith but on common sense.

Mahatma Gandhi preached ahimsa and you talk of kindness. How are the two different or similar?

I dont know. You should examine. But sometimes, I feel my work is more at a mental level, his was more at an action level (laughs). Im a student of the Nalanda tradition. From childhood, we learn logic and psychology.

Do you think Mahatma Gandhi was more of a politician or a spiritual leader?

After he returned from England, Gandhi started the non-violence movement in South Africa. This was purely a moral and spiritual issue. Then he came to India, and practised non-violence. In India as he himself is an Indian, maybe there was some political implication. In South Africa, it was pure theory and philosophy; he was a spiritual leader.

I always consider myself a follower of Mahatma Gandhiji. In the philosophical field, my knowledge may be better than Gandhiji (chuckles) because we study from childhood the Nalanda texts, which deal with quantum physics. When I have discussions with scientists on quantum physics, I respect them, but mentally, I feel I know better (laughs). Quantum physics clearly explains the differences between appearance and reality. In order to tackle our destructive emotions such as anger and extreme attachment, we need to understand this gapthat nothing exists objectively as it appears but is entirely dependent on the observer.

Like Gandhiji, you have faced great challenges in your life in the pursuit of your objective. How do you remain an optimist?

First, I consider myself one of seven billion human beings. I see no difference. Chinese, Tibetan, Indian, European... We are the same, emotionally, physically, mentally. On that level, my commitment is to try to promote peace of mind among seven billion beings, to offer compassion or karuna, strictly secularly, not based on religion.

My second commitment as a Buddhist monk is promotion of religious harmony. I have full confidence that religious harmony is possible. Look at India. For more than 2,000 years, so many religions from outside have lived together alongside the home-grown traditions. There are little problems, but thats mainly because politicians manipulate; but basically, religious harmony is very much alive here.

I always tell Tibetans, it is much better to keep Chinese as our brothers and sisters than consider them as our enemyno use. For the time being, there is a problem with the Chinese neighbour, but that is a few individuals in the Communist Party. A number of Chinese leaders now realize that their 70-year policy regarding Tibet is unrealistic. There was too much emphasis on the use of force. So now they are in a dilemma: How to deal with the Tibetan problem? So things are changing. I think within one or two years, there is a possibility of me visiting China. But I love freedom and I enjoy Indias freedom. Indian freedom over 60 years has spoilt me (laughs).

Is there a link between the conflict in the world and the way we live?

The source of the problem is a self-centred attitude. The antidote is altruism. With greater altruism, the self-centred attitude reduces. This attitude brings anger, hatred and fear. Science has found that the basic human nature is compassionate. Our basic nature is to be social, appreciate the others kindness, smile. Live in kindness.

You said at the start of the interview that you saw Gandhi in your dream. If you were to really meet him today, what would be the first thing you would say to him?

I very much want to meet him, and first, touch his feet. Then, I think he may have some idea about how to deal with China.

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Our world is in need of the Mahatmas teachings: Dalai Lama - Livemint

This One Experiment Reveals More About Reality Than Any Quantum Interpretation Ever Will – Forbes

Today, we conceive of all particles, from the massive quarks to the massless photon, as have a dual wave/particle nature. Light was originally considered to be a particle (or corpuscle) by Newton, but experiments performed in the late 1790s and early 1800s revealed wave properties as well. Today, all quanta appear to exhibit a dual wave/particle nature, and exploring where and how these properties appear can lead us to truly approach an understanding of how our quantum Universe behaves.

Imagine asking the biggest, most fundamental question of all: what is reality? How would you go about answering it? If you took the scientific approach, you'd go down to the smallest indivisible quantum of matter or energy possible, isolate it as much as possible, and then measure its behavior under every bizarre scenario your mind can concoct. The experimental results should provide a window into reality unlike any other, as it compels the laws of physics to reveal themselves.

As bizarre, confusing, and controversial as quantum physics can be, this is the approach taken by the experimental physicists who study the quantum rules behind our Universe. Despite all the attention the different interpretations draw, they don't reveal the nature of our quantum reality nearly as well as a single experiment the double-slit experiment can. Here's what all the fuss is about.

Imagine, before you ever start thinking about particles, that you had a continuous fluid at your disposal in a large tank: something like a pool full of water. At one end, you start generating waves that propagate down the length of the tank, evenly spaced with regular peaks and troughs. In the middle of the pool, however, is an obstacle: a barrier that blocks the waves from propagating any further. The only exception is that there are two holes, or vertical slits, cut into the barrier to allow a tiny fraction of that water through.

What will happen to those water waves? They behave exactly as you'd predict from classical mechanics and the wave equation: two wave sources make it through, one at the site of each slit. As the peaks and troughs reach each other from the two sources, they interfere both constructively and destructively. As a result, at the far end of the tank, you'll get an interference pattern from those two wave sources.

This diagram, dating back to Thomas Young's work in the early 1800s, is one of the oldest pictures that demonstrate both constructive and destructive interference as arising from wave sources originating at two points: A and B. This is a physically identical setup to a double slit experiment, even though it applies just as well to water waves propagated through a tank.

On the other hand, what if you didn't have a continuous fluid, but a slew of discrete particles instead? You'd do the same experiment, except instead of filling your large tank with water, you'd leave it empty. You'll leave the barrier with two vertical slits in place, but this time you'll throw a large number of pebbles down towards the far end of the tank.

Overwhelmingly, the majority of the pebbles will strike the barrier and fail to go through; they won't arrive at the far end of the tank. Only a few pebbles will arrive, and they'll be clustered in two regions: one for the pebbles that slipped through the slit on the left and another for the pebbles that slipped through the slit on the right. A few pebbles might strike the edge of the slit or another pebble, and hence you won't get all the pebbles arriving at the same two locations, but rather they'll be distributed in two straightforward bell curves.

The classical expectation of sending particles through either a single slit (L) or a double slit (R). If you fire macroscopic objects (like pebbles) at a barrier with one or two slits in it, this is the anticipated pattern you can expect to observe.

These are the two classical outcomes you'd expect for a two-slit experiment: one set of results for where you have waves, and a disparate set of results for where you have particles. Now, let's imagine the same experiment, but instead of macroscopic objects like water waves or large numbers of pebbles, we're going to use the fundamental quantum entities provided to us by the Universe.

The first time any human ever did such an experiment, unbelievably, was right at the turn of the 18th century. (Really! The hints of quantum physics are really hundreds of years old!) In the late 1790s and early 1800s, a scientist named Thomas Young was experimenting with light, when he had the brilliant idea to do two things simultaneously:

The results were immediately astonishing.

Double slit experiments performed with light produce interference patterns, as they do for any wave you can imagine. The properties of different light colors is understood to be due to the differing wavelengths of monochromatic light of various colors. Redder colors have longer wavelengths, lower energies, and more spread-out interference patterns; bluer colors have shorter wavelengths, higher energies, and more closely bunched maxima and minima in the interference pattern.

You see, since the 1600s, scientists had followed physics as Newton had laid it out, and Newton insisted that light was not a wave, but was a corpuscle: a particle-like entity that moved in straight, ray-like lines. His treatise on the subject.Opticks, correctly described a large number of phenomena like reflection and refraction, absorption and transmission, how white light was composed of colors and how light rays bent when they transitioned from traveling through one medium (like air) to another medium (like water).

Newton's contemporary, Christiaan Huygens, concocted a wave theory of light, but it couldn't account for Newton's experiments with prisms. The idea that light could be a wave fell out of favor more than 100 years earlier, but Young's double slit experiments brought them back. Unambiguously, light passed through a double slit exhibited wave-like, not particle-like, properties.

Schematic animation of a continuous beam of light being dispersed by a prism. Note how the wave nature of light is both consistent with and a deeper explanation of the fact that white light can be broken up into differing colors.

Subsequent experiments with light confirmed its wave-like properties, and Maxwell's formulation of electromagnetism allowed us to finally derive that light was an electromagnetic wave that propagated atc, the speed of light in a vacuum. But what's going on with light at a fundamental level?

Here are three of the most thoroughly considered options:

In the early 1900s, experiments began to discriminated between these options. Einstein's work on the photoelectric effect was decisive, as it demonstrated that only light of a short-enough (i.e., blue enough and energetic enough) wavelength was capable of knocking loosely-held electrons off of a metal.

The photoelectric effect details how electrons can be ionized by photons based on the wavelength of individual photons, not on light intensity or any other property. Above a certain wavelength threshold for the incoming photons, regardless of intensity, electrons will be kicked off. Below that threshold, no electrons will be kicked off, even if you turn the intensity of the light way up.

Since electrons were particles, photons had to behave as particles, too. But that double slit experiment sure made it seem like these photons were behaving as waves. Somehow, both of these properties of light that it behaved as a wave when it passed through a double slit but that it behaved as a particle when it struck an electron must simultaneously be true and mutually compatible.

Whenmost people first learn about this, their minds immediately run in a bunch of different directions, trying to make sense of this bizarre and unintuitive aspect of reality. From a physicist's perspective, this translates into imagining what sorts of experiments (or modifications to this one double-slit experiment) one could do to probe reality deeper. The first thing you might think of is to switch out photons, which act as both waves and particles, for something that's known to behave as a particle: an electron.

The wave pattern for electrons passing through a double slit. If you measure "which slit" the electron goes through, you destroy the quantum interference pattern shown here; if you don't measure it, it behaves as though each electron interferes with itself.

So you fire a beam of electrons at a barrier with two slits in it, and look at where the electrons arrive on the screen behind it. Although you might have expected the same result you got for the pebble-experiment earlier, you don't get it. Instead, the electrons distinctly and unambiguously leave an interference pattern on the screen. Somehow, the electrons are acting like waves.

What's going on? Are these electronsinterfering with each other? To find out, we can change the experiment again; instead of firing a beam of electrons, we can send one electron through at a time. And then another. And then another. And then another, until we've sent thousands or even millions of electrons through. When we finally look at the screen, what do we see? The same interference pattern. Not only are the electrons acting like waves, but each individual electron behaves as a wave, and somehow manages to create an interference pattern only by interacting with itself.

Electrons exhibit wave properties as well as particle properties, and can be used to construct images or probe particle sizes just as well as light can. Here, you can see the results of an experiment where electrons are fired one-at-a-time through a double-slit. Once enough electrons are fired, the interference pattern can clearly be seen.

If this bothers you, you're not alone. Upon observing this phenomenon, physicists repeated it with photons, sending them one-at-a-time through the double slit. The result? Same as it was for electrons: the photons interfere with themselves as they travel through the experiment.

So what else can we do to learn more? We can set up a "gate" at each of the two slits, and ask which one the electron (or photon) actually goes through. The way you do this is to cause an interaction (through a photon interaction or by measuring an electromagnetic effect of a charged particle passing through the slit)if the particle you're firing passes through your slit.

You do the experiment. Electron #1 goes through the right slit. So does electron #2. Then electron #3 goes through the left slit. #4 goes right, #5 and #6 go left, etc. After thousands of electrons, you record them all. And your screen, instead of showing an interference pattern, shows two non-interfering piles.

If you measure which slit an electron goes through, you don't get an interference pattern on the screen behind it. Instead, the electrons behave not as waves, but as classical particles.

It's as though the act of observing or forcing an energy-exchanging interaction destroys the wave-like behavior and forces particle-like behavior instead. You can then apply all sorts of tweaks, and see what happens. For example:

A quantum eraser experiment setup, where two entangled particles are separated and measured. No alterations of one particle at its destination affect the outcome of the other. You can combine principles like the quantum eraser with the double-slit experiment and see what happens if you keep or destroy, or look at or don't look at, the information you create by measuring what occurs at the slits themselves.

This is fascinating stuff, and is really just the tip of the iceberg for quantum physics.If you set up your apparatus in a particular configuration, you can measure the outcome of any such experiment you perform. What happens if you force the interaction between a photon and the electron as it passes through the slit, but never record the information? What happens if you don't look at the information you do record, but look at the screen before you ever look at the information? If you then go and destroy the information and look at the screen again, does anything change?

Each experimental setup will give you a unique set of results, and each result you get provides you with a little piece of information about the quantum picture of our Universe. If you want to know what reality is, it's this: what we can observe, measure, and predict about nature under every combination we can dream of setting up. To learn more, we have to look to experiments and observations. Those results, rather thanwhich quantum interpretation you accept, show us what's truly real.

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This One Experiment Reveals More About Reality Than Any Quantum Interpretation Ever Will - Forbes

Physicists race to develop room-temperature quantum chips – The Next Web

A team of physicists from Stevens Institute of Technology recently unveiled the worlds most complex and accurate method for coaxing individual particles of light into interacting with one another. While bullying photons might not sound like a breakthrough, the teams research is blazing a trail towards the Holy Grail of physics: room-temperature quantum computing chips.

The Stevens team, led by associate professor of physics and director of the Center for Quantum Science and Engineering Yuping Huang, developed a method for forcing photons to interact by etching a quantum-sized micro-cavity in the shape of a racetrack into a lithium niobate crystal compound. They then fired a precision laser into the compound which interacted with the individual photons in a manner that allowed the researchers to tune it forincredibly specific results.

Credit: Chen et, al.

Creating the micro-cavity was no small feat, it required the development and use of entirely new tools and techniques. According to a press release from Stevens, the precision with which the group can now force single-photon interactions sets them squarely on the path towards room-temperature quantum computing:

Theyre closing in on a system capable of generating interactions at the single-photon level reliably, a breakthrough that would allow the creation of many powerful quantum computing components such as photonics logic gates and entanglement sources, which along a circuit, can canvass multiple solutions to the same problem simultaneously, conceivably allowing calculations that could take years to be solved in seconds.

Were not quite there yet. Its one thing to merely cause interactionsat the single-photon level and another to wield the god-like power that would allow us to reliably control these interactions. What makes this experiment such an eureka moment is that it clearly demonstrates that we can achieve room-temperature quantum computing, and the Stevens team has already figured out some things they can try out to improve their accuracy in the next experiments.

There are other teams, around the globe, trying to solve these very same problems. We may be years or decades from seeing the fruits of their labors manifest as full-fledged room-temperature quantum communications systems, but the path to the Grails been revealed and the quest has begun.

Credit: Chen et, al.

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Physicists race to develop room-temperature quantum chips - The Next Web


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