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Category Archives: Quantum Physics

Outstanding Seniors in the College of Science: Justin Hink – University of Arizona News

Posted: May 3, 2022 at 10:02 pm

This spring, each department in the University of Arizona's College of Science nominated an outstanding senior who went above and beyond during their time as a Wildcat. We are pleased to share their stories as they reflect on their time at UArizona. Next up in the senior spotlight series is Justin Fink.

Hometown: Marana, AZ

Degrees: Physics and Astronomy

College of Science:Why did you choose your area of study?

Justin: At Marana High School, I started learning physics sophomore year. My teacher, Mark Calton, taught me Newtons kinematic equations. I thought it was fascinating to learn so much about the motion of objects from a few initial conditions. I had started an engineering club with Mark where we created trebuchets, a duct tape water bottle, a duct tape boat, and many other projects. I used my introductory physics knowledge to know how much force our trebuchet was applying and the distance the golf ball would travel. I wanted to learn more. I went through two years of AP physics classes learning thermodynamics, optics, electromagnetism, and quantum mechanics, of course, all in a simplistic manner. I was able to take an Astronomy course with Mark as well. My physics classes and teacher got me out of my bubble and convinced me to put in the effort necessary to take on and achieve this degree.

COS:Tell us about a class or research project you really enjoyed.

Justin: The most memorable research project I have worked on throughout these four years of college was with the Thomas Jefferson National Accelerator Facility (JLab). I have worked with them since the summer after my junior year. This was the first time I had to search through textbooks and teach myself a topic for research. This experience gave me an abundance of opportunities, from seminars to writing papers, all the way to a poster presentation at Rice University. This internship even led me to learn more about medical physics and change the direction of my career.

COS:What is one specific memory from your time at UA that you'll cherish forever?

Justin: I will always remember going up to Mt Lemmon with a group of astronomy friends. They had an 8 telescope so we could see the rings of Jupiter. It is a whole new experience to see the rings in person rather than a nice picture online. Surprisingly, it was my first time on Mt Lemon, even though I have lived here my whole life.

COS:What is next for you after graduation?

Justin: After graduation, I am working with the Thomas Jefferson National Accelerator Facility over the summer. Then, I am moving on to UCLA this coming Fall. I was accepted into their Department of Physics and Biology in Medicine to work towards a Medical Physics Ph.D.

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Doctor Strange: Could we really be living in a multiverse? – BBC Science Focus Magazine

Posted: at 10:02 pm

In a parallel universe, you are writing this article. Youre probably doing a better job of it too. Thats what the multiverse theory suggests, anyway. You will no doubt have heard of it, if not from science then certainly from science fiction.

Star Trek, Stranger Things, Spider-Man: No Way Home TV and film is full of stories set around the idea that our world is but one of many alternative realities. However, with the release of the new Marvel film, Doctor Strange In The Multiverse Of Madness, the theory is set to achieve new heights of popularity.

But what exactly is the multiverse? And is there any truth to the idea that in a different reality Im actually a rich, handsome Premier League footballer?

The multiverse derives from the basic idea that beyond the grand sphere of our observable Universe are entirely different universes, distantly separated from ours. What characterises these universes is up for debate, but Richard Bower, professor of cosmology at Durham University, cites the work of fellow cosmologist Max Tegmark, who has theorised four levels of multiverse.

The first, explains Bower, posits an infinite universe in which every possibility that could happen would happen, including another copy of Earth. Level two, meanwhile, gives us multiverses where the basic laws of physics are the same, but fundamental constants differ. Newtons law of gravity would still weaken with distance, says Bower, but maybe there are four spatial dimensions instead of three.

Level four goes even further, presenting multiverses that have entirely different laws of physics. So maybe there would be some sort of mathematics that we have no idea about, says Bower. It could get weird. The trailers for the new Doctor Strange movie suggest an embrace of these weirder versions of the multiverse, with one shot showing him trapped in some sort of cuboid dimension.

Elizabeth Olson as Wanda Maximoff in Doctor Strange In The Multiverse Of Madness Disney

But of course, the most popular iteration of the multiverse is level three, the many worlds interpretation of quantum mechanics. It states that every choice causes a split in the Universe, leading to infinite parallel realities. In popular culture, its the theory behind the multiple Spider-Men in Spider-Man: No Way Home.

There are many versions of you but youre only aware of one of those versions, explains Bower, who cites the famous Schrdingers cat experiment. Youre seeing a cat thats either alive or dead, and youre incapable of realising that theres a version of you where the cat is alive. Youre just conscious of the version where the cat is dead.

None of this has been proven, however. There are theories that if a neighbouring universe happened to collide with ours some time ago, it may have left behind proof in the form of cold or hot spots on the cosmic microwave background (electromagnetic radiation left over from the Big Bang).

Bower himself is optimistic that advances in quantum computing which utilises properties of quantum mechanics like entanglement and superposition could demonstrate the strength of the many worlds interpretation. But at the moment, all of this is hypothetical. In fact, many scientists believe the mystery of whether the multiverse is real to be a philosophical question rather than a scientific one.

I dont totally agree with my colleagues on that, because a lot of them seem to think, Oh, its a philosophical question, and therefore we cant try to address it scientifically, says Bower. No, we just have to be more inventive about how we try to come up with ways to test it and new ways to interpret things.

Who knows, maybe in another universe someone has already figured it all out?

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This Is The Real Scientist Behind The Big Bang Theory – Looper

Posted: at 10:02 pm

"The Big Bang Theory" goes pretty far into incredibly brainy information and advanced theories. As it turns out, all of that information is accurate, fact-checked, and presented in a true manner thanks to the likes of David Saltzberg, a real-life UCLA physics professor.

In an interview with NPR, Saltzberg said of his tenure on the hit series, "This has a lot more impact than anything I will ever do. It's hard to fathom, when you think about 20 million viewers on the first showing and that doesn't include other countries and reruns. I'm happy if a paper I write gets read by a dozen people." According to that same interview, Saltzberg's other function on the show, besides making sure all of the science is correct, was to fill in the appropriate information within the script and on the whiteboards. The whiteboards themselves have an incredible amount of detail when it comes to current scientific understanding, and Saltzberg would often reference real-life theoretical works, much to the delight of actual physicists familiar with the subjects.

When he's not working on shows like "The Big Bang Theory," Saltzberg works with proton colliders, researches neutrinos, and teaches physics classes that range from introductory courses to classes aimed at graduate students at the University of California's Los Angeles campus (via UCLA). Because of Saltzberg's work on "The Big Bang Theory," the show is as scientifically correct as it possibly can be.

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Research in 60 Seconds: Quantum Physics for the Future of Tech – UCF

Posted: April 29, 2022 at 3:35 pm

Whether its solving the worlds biggest problems or investigating the potential of novel discoveries, researchers at UCF are on the edge scientific breakthroughs that aim to make an impact. Through the Research in 60 Seconds series, student and faculty researchers condense their complex studies into bite-sized summaries so you can know how and why Knights plan to improve our world.

Name: Enrique Del Barco

Position(s):Pegasus Professor of Physics and associate dean of Research, Facilities

Why are you interested in this research?Understanding how the microscopic world functions is almost bucolic, as the laws governing this world (quantum mechanics) are absolutely unimaginable from our classical world perspective but explain the most fundamental phenomena with unnumerable repercussions in our day-to-day lives.

Who inspires you to conduct your research?My students. I reflect myself in my students, from high school to the Ph.D. level. They remind me of my youngest self, when I looked at the world with amusement and was looking to understand how everything works. I see this in my students faces when they are in the lab trying to unveil the next secret of the microscopic world.

Are you a faculty member or student conducting research at UCF? We want to hear from you! Tell us about your research at bit.ly/ucf-research-60-form.

How does UCF empower you to do your research?UCF has offered me the opportunity to build an extremely competitive research laboratory and has continuously supported me during the years in basically every single need I have had while putting me in contact with an amazing population of brilliant students.

What major grants and honors have you earned to support your research?I have received numerous grants from multiple external sponsors, including the U.S. National Science Foundation and the U.S. Department of Defense, that amount to over $12 million. This funding has been essential to support the research activities conducted in my group. As the main recognition that I have received from my colleague scientists was becoming fellow of the American Physical Society in 2017 for my accomplishments in nanoscale magnetism research.

Why is this research important?Our research in nanoscale spintronics has strong potential to represent a breakthrough in technology. To provide an example, spintronics-based circuitry may end consuming one thousand times less energy than the most advanced electronic technology. Only this would represent a revolution, as currently energy consumption by electronic circuits (including computers) represents one of the most important expenses of energy in the world, contributing significantly to our climate change. Decreasing this by a thousand would be amazing!

Are you a faculty member or student conducting research at UCF? We want to hear from you! Tell us about your research at bit.ly/ucf-research-60-form.

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The quantum wave function isn’t real | Eddy Keming Chen – IAI

Posted: at 3:35 pm

The dominant interpretation of the quantum wave function sees it as real as part of the physical furniture of the universe. Some even go as far as to argue that the entire universe is a quantum wave function. But this interpretation runs into a number of problems, including a clash with Einsteins theory of relativity. Karl Popper prize-winner, Eddy Keming Chen, suggests that we instead interpret the wave function as the basis for a law of nature that describes how particles, fields and ordinary objects move through space and time. That way, a number of puzzles around quantum mechanics are resolved.

Believe me when I say it's easy to love quantum mechanicsthe fundamental rules that describe our physical world, starting at the microscopic level but hard to interpret what its really about. Quantum mechanics is unquestionably useful as an algorithm for predicting the outcomes of experiments and has given birth to many technological innovations from MRIs to semiconductors. But when it comes to the question of what quantum mechanics tells us about the nature of physical reality, things get very complicated, very quickly. Does quantum mechanics really reveal what exists at the fundamental level of the universe?

Reality is just a quantum wave functionRead moreSuch questions are at the heart of the foundations of physics. Physicists and philosophers have debated them since the early days of quantum mechanics. And while there are many divergent interpretations, most of them agree that uncovering the physical reality of the quantum world requires us to come to terms with the wave function - the central mathematical object used in quantum mechanics. But what is the wave function? We have invented a beautiful mathematical framework to talk about the wave function, but it is very hard to give a physical interpretation of its abstract mathematics. One dominant interpretation of the wave function is that it in fact represents physical reality some even argue that the universe as a whole is just a quantum wave function. But that interpretation runs into a number of problems. What I suggest is that we stop thinking of the wave function as real, as part of physical reality, and instead interpret it as providing the basis for a simple law of nature.

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At first glance, the wave function stands to quantum mechanics as particles to classical mechanics and electromagnetic fields to classical electrodynamics. The wave function of quantum mechanics seems to have all the marks of something real, indispensable, and should presumably be just as much a part of the constitution of physical reality as ordinary objects like tables and chairs. This might motivate one to adopt a realist interpretation of the wave function. Proponents of this view include many prominent physicists and philosophers such as Sean Carroll, David Albert, and Alyssa Ney. Yet, compared to particles and electromagnetic fields, the wave function is a highly abstract mathematical object that lives in a high-dimensional space, and includes imaginary numbers. It is far from clear how the wave-function is connected to our ordinary world of physical reality.

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The task of interpreting quantum mechanics, I argue, becomes easier if we reject the orthodox view that the quantum universe must be described by a wave function (a pure state, in technical terms). We should reconsider the realist interpretations of the wave function. Instead of thinking of quantum mechanics as telling us that, at the fundamental level, the universe is actually a wave function, we should think of it as providing us with the basis for a simple law of nature, one that determines how ordinary physical objects, such as particles and fields, move in space and time.

To motivate the new picture, let me summarize some of the problems facing the realist interpretations of the wave function. First, if we take seriously the space on which the wave function is defined, we might need to accept that the real arena where physical events unfold is a space of extremely high dimensions - about 10 to the power of 80, which is a huge number. While we may believe our universe may contain the 20+ dimensions postulated by some versions of string theory, it is much harder to swallow the idea that in fact, the real number of dimensions of the universe is 10 to the power of 80. It is difficult to see how ordinary four-dimensional objects like dogs and cats can emerge from it.

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Second, if we assume that the wave function is a physical object living in four-dimensional spacetime, it leads to a surprising kind of holism. Suppose we have a group of particles in spacetime. The wave function would endow the group with properties that cannot be derived from properties of the individual particles. The whole is, as it were, more than its parts. That is related to what is called quantum entanglement.

Finally, realist interpretations of the wave function seem to be in tension with Einsteins relativity theory a pillar of modern physics. If there is no objective and unique way of slicing spacetime into space and time, as relativity theory tells us, admitting quantum entanglement as a fundamental feature of the physical world makes it difficult to describe the full history of the universe. As David Albert argues, the history of a quantum universe on one way of slicing spacetime cannot be related to that on another, just by changing the reference frame. Instead, it requires details about the laws of nature.

Hence, we already have motivations to seek an alternative to the realist interpretations of the wave function as a physical object. According to an earlier proposal (due to Detlef Drr, Sheldon Goldstein, Stefan Teufel, and Nino Zangh), the wave function of the universe is not a physical object, but a physical law, like Newtons second law of motion. The wave function determines the motion of physical objects - both at the quantum level, and at the everyday level - such as particles, fields, tables and chairs. My proposal is inspired by theirs, but I suggest there is an easier and simpler way to implement the idea.

A hypothetical wave function of the universe is fairly complex. As it carries so much information, it can be complicated to specify. Because of its complexity, it does not look like a law of nature, which we expect to be relatively simple, like the expression for the law of universal gravitation and Newtons second law F = m a.

I suggest that we take a step back, by zooming out a bit. There is a mathematically well-defined way to do so (yielding what is known as the density matrix) but let me use a metaphor. Think of each possible wave function as a pixel on a screen. Think of the wave function of the actual universe as a particular pixel marked in red. If we have a powerful microscope, we see every dot on the screen, including the red dot. Specifying the location of the red dot requires a lot of information. Now, if we adjust the magnification and zoom out a bit, we stop seeing individual pixels. At the right level of magnification, we see some pattern emerging. The pattern, being more coarse-grained, can be easier and simpler to describe than the exact locations of individual pixels. I suggest that such a coarse-grained pattern suffices as a law describing the motion of ordinary physical objects. This less detailed description is given by a density matrix.

If we zoom out too much, there is the danger of throwing away too much information and hence missing out on the pattern. So what is the right level of magnification to use? The answer to that question relates to another remarkable feature of our world---the arrow of time. Even though the microscopic dynamical laws do not distinguish between the past and the future, our ordinary experience is full of processes that do. Just think of the melting of ice, the spreading of smoke, and the decaying of fruits. The universe appears more orderly in the past and less orderly in the future. This observation is summarized in the Second Law of Thermodynamics, according to which isolated systems tend to increase in entropy, a measure of disorder. What is responsible for this arrow of time? A standard answer is to add a fundamental axiom or a law of nature called the Past Hypothesis, according to which the universe started in a special state of very low entropy, at or near the Big Bang. Such a state can be characterized in relatively simple terms using macroscopic variables such as entropy, temperature, density, and volume. The Past Hypothesis, as it were, picks out the magnification level for the microscope. It strikes the perfect balance and selects just the right amount of information we need for specifying a simple and yet empirically adequate law.

Because of the simplicity of the Past Hypothesis, the coarse-grained pattern obtained from it can be described by a remarkably simple object. It carries much less information than a hypothetical wave function. It is sufficiently simple to be a candidate law of nature and sufficiently informative to determine the motion of ordinary objects. As a result, we do not need to reify the wave function as either a physical object or a physical law. This has two implications. First, it shows that conceptual issues about the arrow of time are intimately connected to the interpretations of quantum mechanics. Second, it provides an attractive alternative to realist interpretations of the wave function.

I develop this idea in a proposal called the Wentaculus. (The name comes from the word Mentaculus, which, as used in the Cohen Brothers movieA Serious Man, means the probability map of the universe. In the philosophy of science literature, David Albert and Barry Loewer have named their theory the Mentaculus. For my proposal, Ive changed M to W as the latter is used to denote a density matrix.) The picture of the world it offers is easier to embrace than the realist interpretations of the wave function. The quantum universe includes ordinary objects made of particles, fields, and / or other localized entities. The wave function is no longer central in this theory as either a physical object or a physical law. Instead, we postulate a much more coarse-grained and simpler object that naturally arises from considerations about the Past Hypothesis. The simple object represents a law of nature determining the motion of ordinary objects.

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The Wentaculus reduces the types of randomness in the world. On the orthodox view, the outcomes of quantum experiments are random, and the randomness is predicted (probabilistically) by the wave function. However, the wave function itself is also chosen at random from a collection of many different hypothetical wave functions, and such randomness is an additional postulate in the theory. On the Wentaculus, the second postulate of randomness is eliminated; there is only one physically possible quantum state and it is not random at all.

Moreover, the Wentaculus unifies the universe with its subsystems (small parts of the universe). On the orthodox view, the universe is described by a wave function, but most subsystems cannot be described by wave functions because of the phenomenon of quantum entanglement. On the Wentaculus view, the entire universe---including all of its parts---can be described by the same mathematical equations.

Furthermore, the Wentaculus version of Everetts many-worlds quantum mechanics is the first realistic and simple example of strong determinism, the idea (introduced by Roger Penrose) that laws of nature allow only one possible model of physical reality. On the orthodox version of Everetts theory, the wave function gives rise to many different and parallel branches, each realizing a different history. All of them are real and included in a gigantic multiverse, a much larger version of what we commonly regard as the physical reality. However, on the orthodox version of Everetts theory, there can be different wave functions and hence different multiverses. The actual multiverse could be any one of them. In other words, physical reality is not pinned down by the laws of nature, as they allow distinct models of the multiverse. On the Wentaculus version of Everett, in contrast, the laws of nature completely specify the multiverse, so there is only one way physical reality could be. In other words, the actual multiverse could not have been different on pain of violating physical laws.

The orthodox view assumes that, if physical reality is quantum mechanical, the universe must be described by a wave function. This view leads to difficulties, because the wave function is not something we can easily regard as a physical object (as it is too abstract) or a physical law (as it is too complicated). The situation is transformed when we zoom out a bit. The most natural object of quantum mechanics compatible with the Past Hypothesis becomes simple enough to be a law of nature.

Quantum mechanics is hard to interpret. We can make progress if we stop being realists about the quantum wave function, and zoom out.

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Lasers and Ultracold Atoms Combine in One-of-a-Kind Lab – Dartmouth News

Posted: at 3:35 pm

Fully understanding the complexity of Kevin Wrights laboratory in Wilder Hall would require a deep knowledge of ultracold quantum physics. But who has time for that? Understanding a hot cup of coffee could do just fine.

To visualize what it means for something to be a superfluid, imagine stirring your coffee with a spoon, then removing it, explainsWright, assistant professor of physics and astronomy. And then imagine that the coffee keeps swirling in circles forever, never coming to rest.

Now imagine that the never-ending swirling coffee is not being stirred by a spoon but by a web of laser beams that crisscross in a way that somehow makes perfect sense in the spooky world of quantum physics.

And instead of coffee, its a cloud of lithium atoms thats swirling around.

Welcome to the worlds first tunable superfluid circuit that uses ultracold electron-like atoms. That maze of laser light and cloud of superfluid atoms are part of a one-of-a-kind microscopic test bed designed by Wright to explore how electrons work in real materials.

A web of lasers allow researchers to cool, move, and detect electron-like atoms in the superfluid circuit. (Photo by Robert Gill)

Much of modern technology revolves around controlling the flow of electrons around circuits, says Wright. For the first time, researchers can now analyze the strange behavior of these kinds of quantum particles in a highly controllable setting.

While common conductive materials such as copper are well understood, researchers do not fully know how electrons move or can be controlled in exotic materials like superconductors.

The challenge is isolating and controlling individual electrons to study their behavior. The novelty of Wrights circuit is that it uses a complete atom to demonstrate how one of its single, fundamental parts behaves. Unfortunately, there is no coffee analogy that suffices here, but according to Wright, We are learning about electrons without using electrons.

Kevin Wright, assistant professor of physics and astronomy. (Photo by Robert Gill)

Further comprehending Wrights research requires the understanding that atomic particles can be either bosons or fermions. Bosons, such as photons, tend to bunch together. Fermions, such as electrons, tend to avoid each other.

While superfluid circuits using ultracold boson-like atoms already existpioneered by Wright when he was at the National Institute of Standards and Technologythe Dartmouth circuit is the first to use ultracold atoms that act as those asocial fermions.

Electrons can do things that are far stranger and more rich than anyone has imagined, says Wright. By using electron-like atoms, we can test theories in ways that were not possible before.

Lithium-6 makes the work possible. Although the isotope is a complete atom with a nucleus, protons and electrons, it behaves like an electron. The lasers are used to cool the lithium to temperatures near absolute zero and then to move the atoms around in ways that mimic electrons flowing around superconducting circuits. The lasers also detect how the atoms are acting and even provide the structure of the circuita microscopic racetrack in an ultrahigh vacuum chamber for the atoms to circle around.

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By using electron-like atoms, we can test theories in ways that were not possible before.

Attribution

Kevin Wright, assistant professor of physics and astronomy.

Spread across three stainless steel optical tables stretching about 18-feet wide, the test bed gives physicists access to a quantum emulator that will allow them to study the formation and decay of currents that flow indefinitely without added energythat imaginary endlessly swirling coffee.

The labs success in creating the superfluid environment is detailed in a recent study written by Yanping Cai, Guarini 21,Daniel Allman, Guarini 23,Parth Sabharwal, Guarini 24, and Wright that was published inPhysical Review Letters.

Yanping Cai, Guarini 21; Parth Sabharwal, Guarini 24; and Daniel Allman, Guarini 23. (Yanping Cai-Courtesy of Yanping Cai; Parth Sabharwal-Courtesy of Parth Sabharwal; Daniel Allman- photo by Robert Gill)

Its amazing to be a part of something that nobody has ever done, says Allman, who Wright credits with being a master troubleshooter in the lab. This is the frontier of new research, and it is cool.

Wrights lab puts Dartmouth at the center of experimental research using ultracold fermions and has the potential to attract researchers looking to test theories and analyze special materials. Findings from the lab could also create opportunities for the development of new kinds of devices that use superconductors and other exotic quantum materials that can be useful for quantum computers.

We have crossed the threshold to build test circuits with fermionic quantum gases, says Wright with a hint of modest pride. Designing and controlling the atom flow around a circuit with ultracold fermions in the same way that is done in an electronic device has just never been accomplished before.

Daniel Allman, left, and Kevin Wright observe a ring of Lithium-6 atoms in the microscopic circuit. (Photo by Robert Gill)

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A regular person’s guide to the mind-blowing world of hybrid quantum computing – The Next Web

Posted: at 3:35 pm

Stephen Hawking once suggested Albert Einsteins assertion that God does not play dice with the universe was wrong. In Hawkings view, the discovery of black hole physics confirmed that not only did God play dice, but that he sometimes confuses us by throwing them where they cant be seen.

Are we here by chance or design?

A more pragmatic approach to the question, considering the subject matter, would be to assume that all answers are correct. In fact, thats the basis of quantum physics.

Heres the simplest explanation of how it all works that youll ever read: imagine flipping a coin and then walking away secure in the knowledge that it landed on heads or tails.

If we look at the entire universe and start zooming in until you get down to the tiniest particles, youll see the exact same effect in their interactions. Theyre either going to do one thing or another. And, until you observe them, that potential remains.

With all that potential out there in the universe just waiting to be observed, were able to build quantum computers.

However, like all things quantum, theres a duality involved in harnessing Gods dice for our own human needs. For every mind-blowing feat of quantum engineering we come up with just wait until you read about laser tweezers and time crystals we need some grounded technology to control it.

In reality, theres no such thing as a purely-quantum computer and there probably never will be. Theyre all hybrid quantum-classical systems in one way or another.

Lets start off with why we need quantum computers. Classical (or binary, as theyre often called) computers the kind youre reading this on complete goals by solving tasks.

We program computers to do what we want by giving them a series of commands. If I press the A key on my keyboard, then the computer displays the letter A on my screen.

Somewhere inside the machine, theres code telling it how to interpret the key press and how to display the results.

It took our species approximately 200,000 years to get that far.

In the past century or so, weve come to understand that Newtonian physics doesnt apply to things at very small scales, such as particles, or objects at particularly massive scales such as black holes.

The most useful lesson weve learned in our relatively recent study of quantum physics is that particles can become entangled.

Quantum computers allow us to harness the power of entanglement. Instead of waiting for one command to execute, as binary computers do, quantum computers can come to all of their conclusions at once. In essence, theyre able to come up with (nearly) all the possible answers at the same time.

The main benefit to this is time. A simulation or optimization task that might take a supercomputer a month to process could be completed in mere seconds on a quantum computer.

The most commonly cited example of this is drug discovery.In order to create new drugs, scientists have to study their chemical interactions. Its a lot like looking for a needle in a never-ending field of haystacks.

There are near-infinite possible chemical combinations in the universe, sorting out their individual combined chemical reactions is a task no supercomputer can do within a useful amount of time.

Quantum computing promises to accelerate these kinds of tasks and make previously impossible computations commonplace.

But it takes more than just expensive, cutting-edge hardware to produce these ultra-fast outputs.

Hybrid quantum computing systems integrate classical computing platforms and software with quantum algorithms and simulations.

And, because theyre ridiculously expensive and mostly experimental, theyre almost exclusively accessed via cloud connectivity.

In fact, theres a whole suite of quantum technologies out there aside from hybrid quantum computers, though theyre the technology that gets the most attention.

In a recent interview with Neural, the CEO of SandboxAQ (a Google sibling company under the Alphabet umbrella), Jack Hidary, lamented:

For whatever reason, the mainstream media seems to only focus on quantum computing.

There are also quantum sensing, quantum communications, quantum imaging, and quantum simulations although, some of those overlap with quantum hybrid computing as well.

The point is, as Hidary also told Neural, were at an inflection point. Quantum tech is no longer a far-future technology. Its here in many forms today.

But the scope of this article is limited to hybrid quantum computing technologies. And, for that, were focused on two things:

There are two kinds of problems in the quantum computing world: optimization problems and the kind that arent optimization problems.

For the former, you need a quantum annealing system. And, for everything else, you need a gate-based quantum computer probably. Those are still very much in the early stages of development.

But companies such as D-Wave have been building quantum annealing systems for decades.

Heres how D-Wave describes the annealing process:

The systems starts with a set of qubits, each in a superposition state of 0 and 1. They are not yet coupled. When they undergo quantum annealing, the couplers and biases are introduced and the qubits become entangled. At this point, the system is in an entangled state of many possible answers. By the end of the anneal, each qubit is in a classical state that represents the minimum energy state of the problem, or one very close to it.

Heres how we describe it here at Neural: have you ever seen one of those 3-D pin art sculpture things?

Thats pretty much what the annealing process is. The pin art sculpture thing is the computer and your hand is the annealing process. Whats left behind is the minimum energy state of the problem.

Gate-based quantum computers, on the other hand, function entirely differently. Theyre incredibly complex and there are a number of different ways to implement them but, essentially, they run algorithms.

These include Microsofts new cutting-edge experimental system which, according to a recent blog post, is almost ready for prime time:

Microsofts approach has been to pursue a topological qubit that has built-in protection from environmental noise, which means it should take far fewer qubits to perform useful computation and correct errors. Topological qubits should also be able to process information quickly, and one can fit more than a million on a wafer thats smaller than the security chip on a credit card.

And even the most casual of science readers have probably heard about Googles amazing time crystal breakthrough.

Last year, here on Neural, I wrote:

Googles time crystals could be the greatest scientific achievement of our lifetimes.

A time crystal is a new phase of matter that, simplified, would be like having a snowflake that constantly cycled back and forth between two different configurations. Its a seven-pointed lattice one moment and a ten-pointed lattice the next, or whatever.

Whats amazing about time crystals is that when they cycle back and forth between two different configurations, they dont lose or use any energy.

Heck, even D-Wave, the company that put quantum annealing on the map, has plans to introduce cross-platform hybrid quantum computing to the masses with an upcoming gate-based model of its own.

The quantum computing industry is already thriving. As far as were concerned here at Neural, the mainstream is just now starting to catch a whiff of what the 2030s are going to look like.

As Bob Wisnieff, CTO of IBM Quantum, told Neural back in 2019 when IBM unveiled its first commercial quantum system:

We get to be in the right place at the right time for quantum computing, this is a joy project This design represents a pivotal moment in tech.

According to Wisnieff and others building the hybrid quantum computer systems of tomorrow, the timeline from experimental to fully-implemented is very short.

Where annealing and similar quantum optimization systems have been around for years, were now seeing the first generation of gate-based models of quantum advantage come to market.

You might remember reading about quantum supremacy a few years back. Quantum advantage is the same thing but, semantically speaking, its a bit more accurate. Both terms represent the point at which a quantum computer can perform a given function in a reasonable amount of time that would take a classical computer too long to do.

The reason supremacy quickly went out of favor is because quantum computers rely on classical computers to perform these functions, so it makes more sense to say they give an advantage when used in tandem. Thats the very definition of hybrid quantum computing.

As for whats next? Its unlikely youll see a ticker-tape parade for quantum computing any time soon. There wont be an iPhone of quantum computers, or a cultural zeitgeist surrounding the launch of a particular processor.

Instead, like all great things in science, over the course of the next five, 10, 100, and 1,000 years, scientists and engineers will continue to pass the baton from one generation to the next as they stand upon the shoulders of giants to see into the future.

Thanks to their continuing work, in our lifetimes were likely to see vast improvements to power grids, a resolution to mass scheduling conflicts, dynamic shipping optimizations, pitch-perfect quantum chemistry simulations, and even the first inklings of far-future tech such as warp engines.

These technological advances will improve our quality of life, extend our lives, and help us to reverse human-caused climate change.

Hybrid quantum computing is, in our humble opinion here at Neural, the single most important technology humankind has ever endeavored to develop. We hope youll stick with us as we continue to blaze a trail of coverage at the frontier of this new and exciting realm of engineering.

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Quantum physics, planet formation and wrestling: Three U of T researchers awarded 2022 Guggenheim Fellowships – University of Toronto

Posted: at 3:35 pm

For research projects in quantum condensed matter, the cultural history of wrestlingand the formation of planetary systems, three University of Toronto scholars from the Faculty of Arts & Science have received prestigious2022 Guggenheim Fellowships.

Fellowships are awarded by the John Simon Guggenheim Memorial Foundation and this year the 97th year of the competition just 180 of 2500 applicants received the awards.

When honours like the Guggenheim Fellowships are awarded to multiple Faculty scholars, I am always impressed and fascinated by the diverse disciplines of the winners, saysMelanie Woodin, dean of the Faculty of Arts & Science. This years cohort is no exception. I am very happy that the fellowships will allow each to pursue their exciting and important work, and I congratulate them all.

Here are the three U of T scholars who receivedGuggenheim Fellowships this year:

Yong-Baek Kimis a professor in thedepartment of physics,as well as the director of theCentre for Quantum Materialsand a member of theCentre for Quantum Information & Quantum Control. Kims research focus is theoretical quantum condensed matter physics,which involves the study of matter and its exotic behaviour when subjected to extreme conditions such as low temperature and high pressure. His work has potential applications for diverse quantum technologies, including quantum computing.

I am particularly interested in emergent quantum phases of strongly interacting electrons in quantum materials which may serve as potential platforms for quantum technology, says Kim.

"Receiving the Guggenheim fellowship is a great honor for me. It's wonderful to see that my work is appreciated by peer intellectuals. I have been privileged to meet and work with so many talented people, especially my former and current students, postdoctoral fellows and collaborators. I thank them for generously sharing their insights."

Yanqin Wuis a professor of theoretical astrophysics in theDavid A. Dunlap department of astronomy and astrophysics. Throughout her career, she has studied planets both in and beyond our solar system. Using data gathered by the Kepler planet-hunting space telescope and other observing programs, she studies their internal structure, motions and formation.

Wus Guggenheim Fellowship will allow her to focus on research into proto-planetary disks of gas and dust around newly developing stars structures from which all planets arise. In particular, Wu is investigating an aspect referred to as segmented disks.

"The puzzle is that proto-planetary disks, when observed at sufficiently high resolutions, display prominent bright rings and dark gaps, says Wu. I am proposing ideas to resolve this puzzle and to understand how it affects planet formation.

Says Wu about the fellowship, It is a luxurious honour to be recognized for doing something that one enjoys and working with people one likes.

John Zilcoskyis a professor in thedepartment of Germanic languages and literaturesand theCentre for Comparative Literature. His expertise encompasses modern European literature, psychoanalysis, the art of traveland the history and philosophy of sports.

With the help of the fellowship, Zilcosky will be able to devote time to writing his next book,Wrestling: A Cultural History. In it, he attempts to answer big questions: Why do we wrestle? And why was wrestling humanitys first sport? He will explain why wrestling is not only humankind's oldest sport but also its most significant. The book will trace the history of grappling from early civilizations and mythsthrough the classical,Renaissance and modern eras all the way to todays pro wrestling.

It will also explore wrestlings presence in Indigenous cultures and also women practitioners from the Greek goddess, Palaistra, to todays Gorgeous Ladies of Wrestling (GLOW) television series. And it will delve into the erotic violence that is always just beneath wrestlings surface.

Says Zilcosky:What a thrill! This is a labour of love, returning me to my youth as a high school and U.S. collegiate wrestler. Its exciting that the Guggenheim Foundation finds this project which connects the histories of sport and of civilization compelling. Such recognition reminds me of my conversation with the world and injects me with new energy.

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Do singularities exist in nature? – Big Think

Posted: at 3:35 pm

Aristotle used to say that nature abhors a vacuum. So, he conjectured, there is no such thing. His model accounted for that absence by filling up space with an imponderable substance: the ether.

As students and researchers know, physics abhors singularities. Where we find a singularity, it usually means that the model we are using to describe a physical system or a phenomenon breaks down. Breaking down is a filler expression for something is happening here and we dont know what it is. Figuring out how to avoid singularities opens new possibilities in physics.

Indeed, behind every singularity in physics hides a secret door to a new understanding of the world.

The reader knows that physics is the art of modeling. We describe complex natural systems, such as the sun and the planets orbiting around it thats an easy one in terms of mathematical equations. The equations describe how functions of a variable or a set of variables change in time. In the case of planetary orbits, the equations describe how planets move in space along their orbits.

Singularity as a term is used in many contexts, including within mathematics. The word also appears in speculation about artificial intelligence, such as to describe the day when supposedly machines will become more intelligent than humans. This kind of singularity is something completely different, and it deserves its own essay. For today, lets stick to physics and math.

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Physicists have a love-hate relationship with singularities. On one hand, singularities signal the breakdown of a theory, or of the mathematical model describing the theory. But on the other hand, they can also be a gateway to new discoveries.

Perhaps the most famous singularities in physics have to do with gravity. In Newtonian physics, the gravitational acceleration caused by a body of mass M and radius R is g = GM/R2, where G is the gravitational constant (a measurable number that sets the strength of the gravitational force). Now consider the situation where the radius R of the body shrinks while its mass remains constant. (So, give it a good squeeze.) As R becomes smaller, the gravitational acceleration g becomes larger. In the limit (we love to say in the limit in physics and mathematics), when R goes to zero, the acceleration g goes to infinity. That is a singularity.

Okay, thats what mathematics says. But can this ever happen? This is where things get more interesting.

The quick answer is an emphatic no. First, mass occupies volume in space. If you keep on squeezing the mass to a smaller volume, where does the mass go? Well, you need new physics to think about that!

Classical Newtonian physics cannot handle physics at very small distances. You need to add quantum physics into your model. So, as you squeeze the mass to smaller volumes, quantum effects will help describe what is happening.

First, you need to know that matter itself is not a solid thing. It is made of molecules. Molecules, in turn, are made of atoms. By the time your ball becomes smaller than about one-billionth of a meter, it is no longer a ball at all. It is a collection of atomic clouds superimposed onto one another according to the laws of quantum mechanics. The very notion of an object being a ball ceases to have any meaning.

What if you could keep on squeezing this atomic cloud to smaller and smaller volumes? Well, you need to include the effects from Einsteins theory of relativity that says that a mass curves the space around it. Not only is the notion of a ball long gone now the very space around it is warped. Indeed, when the supposed radius of the supposed ball reaches a critical value,R = GM/c2, where c is the speed of light, what we had supposed to be a ball becomes a black hole!

Now we are in trouble. The black hole we formed creates an event horizon around it with the radius we just calculated. This is called the Schwarzschild radius. Whatever happens inside this radius is hidden from us on the outside. If you choose to go in there, you will never emerge to tell the story. As the pre-Socratic philosopher Heraclitus once quipped, nature loves to hide. A black hole is the ultimate hideout.

In our exploration, we started with an ordinary ball of ordinary material. We soon needed to expand our physics to include quantum physics and Einsteins general relativity. The singularity that exists by simply taking the limit of a variable to zero (the radius of the ball in our case) was the gateway to new physics.

But we finish this journey with the very unsatisfying feeling of a mission not accomplished. We do not know what goes on inside the black hole. If we push our equations at least Einsteins equation we get a singularity at the very center of the black hole. Here, gravity itself goes to infinity. Physicists call this a singularity point. It is a place in the universe that exists and does not exist at the same time. But then, we remember quantum physics. And quantum physics tells us that a point located in space means infinite precision of position. Such infinite precision cannot exist. Heisenbergs Uncertainty Principle tells us that a singularity point is actually a jittery thing, moving about every time we try to locate it. This means we cannot get to the center of a black hole, even in principle.

So, if we are to take our theories seriously, the mathematical singularity that appears in our models not only opens the door to new physics it also cannot exist in nature. Somehow, and we do not know how, nature finds a way to get around it. Unfortunately to us, this trick seems beyond the reach of our models, at least for now. Whatever it is that goes on inside a black hole, as tantalizing as it is to our imagination, needs a physics we do not yet have.

To make our exploration even more difficult, we cannot get data from inside there. And without data, how are we to decide which one of our new models makes sense? No wonder Einstein did not like black holes, creations of his own theory. As the realist that he was, discovering aspects of the natural world that are beyond our grasp was exasperating.

Here, perhaps, we find a new lesson. Although we should keep trying to figure this out, we should also embrace the mindset that it is okay not to find answers to all of our questions. After all, not knowing is what propels us to keep on looking. As the English playwright Tom Stoppard once wrote, Its wanting to know that makes us matter. Even if our question is unanswerable in the end.

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The Matter of Everything review: A pacy look at 20th-century physics – New Scientist

Posted: at 3:35 pm

From the discovery of the first subatomic particle to the confirmation of the Higgs boson in 2012, Suzie Sheehy's account of experiments that changed our world is detailed but lively

By Elle Hunt

The Large Hadron Collider at CERN near Geneva, Switzerland

Maximilien Brice/CERN

The Matter of Everything

Suzie Sheehy

Bloomsbury

IN 1930, Austrian physicist Wolfgang Pauli set out to solve a mystery. The variability of energy values for beta particles, defying the basic scientific principles of conservation of energy and momentum, had been confounding physicists since the turn of the century.

Pauli a physicist so rigorous in his approach that he had been called the scourge of God seemed well-placed to address it. And yet, when he put his mind to finding a theoretical solution for the problem of beta decay, Pauli created only further ambiguity.

He proposed the existence of an entirely new, chargeless and near-massless particle that would allow for energy and momentum to be conserved, but would be almost impossible to find. I have done a terrible thing, he wrote. I have postulated a particle that cannot be detected.

Pauli, a pioneer of quantum physics, is one of many names to cross the pages of The Matter of Everything, Suzie Sheehys lively account of experiments that changed our world. Through 12 significant discoveries over the course of the 20th century, Sheehy shows how physics transformed the world and our understanding of it in many cases, as a direct result of the curiosity and dedication of individuals.

Sheehy is an experimental physicist in the field of accelerator physics, based at the University of Oxford and the University of Melbourne, Australia. Her own expertise makes The Matter of Everything a more technical book than the framing of 12 experiments might suggest, and certainly more so than the average popular science title, but it is nonetheless accessible to the lay reader and vividly described.

From experiments with cathode rays in a German lab in 1895, leading to the detection of X-rays and to the discovery of the first subatomic particle, to the confirmation of the Higgs boson in 2012, The Matter of Everything is an opportunity to learn not just about individual success stories, but the nature of physics itself.

Sheehy does well to set out the questions that these scientists wanted to answer and what lay at stake with their discoveries, on the macro level as well as the micro one, showing how physics not only helped us to understand the world, but shaped it. These early firsts came from small-scale experiments, with researchers operating their own equipment and even building it from scratch.

The Matter of Everything also highlights those whose contributions might have historically been overlooked, such as Lise Meitner, dubbed the German Marie Curie by Albert Einstein. Her work on nuclear fission went unacknowledged for some 50 years after her colleague Otto Hahn was solely awarded the Nobel prize in 1944.

The commitment and collaboration of physicists and engineers through the second world war showed what was possible for good and evil. Sheehy describes how the development of the bombs that destroyed Hiroshima and Nagasaki awakened a social conscience in the field, paving the way to the international cooperation we see today, such as on the Large Hadron Collider.

United behind a common goal, and with cross-government support, answers that had never before seemed possible suddenly appeared within grasp. To Sheehy, this is evidence of the potential for physics to overcome the challenges that face science and society now from the nature of dark matter to tackling the climate crisis.

At the start of the 20th century, she points out, it was said that we knew everything there was to know about the universe; by the end of the century, the world had changed beyond recognition.

The terrible particles Pauli proposed which he called neutrons, but we now know as neutrinos were finally confirmed in 1956. His response was quietly triumphant: Everything comes to him who knows how to wait.

A sweeping but detailed and pacy account of 100 years of scientific advancement, The Matter of Everything has a cheering takeaway. What such leaps lie ahead? What questions seem intractable now that we wont give a thought to in the future?

Sheehy mounts the case that with persistence, curiosity and collaboration we may yet overcome challenges that now seem impossible.

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