Category Archives: Quantum Physics

The researchers show frequencies of spatially separated clocks can be compared more precisely

The researchers show frequencies of spatially separated clocks can be compared more precisely

An experiment carried out by the University of Oxford researchers combines two unique and one can say even mind-boggling discoveries, namely, high-precision atomic clocks and quantum entanglement, to achieve two atomic clocks that are entangled. This means the inherent uncertainty in measuring their frequencies simultaneously is highly reduced.

While this is a proof-of-concept experiment, it has the potential for use in probing dark matter, precision geodesy and other such applications. The two-node network that they build is extendable to more nodes, the researchers write, in an article on this work published in Nature recently.

Atomic clocks grew in accuracy and became so dependable that in 1967, the definition of a second was revised to be the time taken by 9,19,26,31,770 oscillations of a cesium atom. At the start of the 21st century, the cesium clocks that were available were so accurate that they would gain or lose a second only once in about 20 million years. At present, even this record has been broken and there are optical lattice clocks that are so precise that they lose a second only once in 15 billion years. To give some perspective, that is more than the age of the universe, which is 13.8 billion years.

The more mundane uses to which these clocks can be put include accurate time keeping in GPS, or monitoring stuff remotely on Mars.

If you can measure the frequency difference between these two clocks that are in different locations, that opens up a host of applications, says Raghavendra Srinivas, from the Department of Physics, Clarendon Laboratory, University of Oxford, U.K., who is an author of the Nature paper.

Their work is a proof-of-principle demonstration that two strontium atoms separated in space by a small distance, can be pushed into an entangled state so that a comparison of their frequencies becomes more precise. Potential applications of this when extended in space and including more nodes than two, are in studying the space-time variation of the fundamental constants and probing dark matter deep questions in physics.

In quantum physics, entanglement is a weird phenomenon described as a spooky action at a distance by Albert Einstein. Normally, when you consider two systems separated in space that are also independent and you wished to compare some physical attribute of the two systems, you would make separate measurements of that attribute and this would involve a fundamental limitation to how precisely you can compare the two for two separate measurements have to be made.

On the other hand, if the two were entangled, it is a way of saying that their physical attributes, say spin, or in this case, the frequency, vary in tandem. Measuring the attribute on one system, tells you about the other system. This in turn improves the precision of the measurement to the ultimate limit allowed by quantum theory.

Quantum networks of this kind have been demonstrated earlier, but this is the first demonstration of quantum entanglement of optical atomic clocks.

Dr. Srinivas says, The key development here is that we could improve the fidelity and the rate of this remote entanglement to the point where its actually useful for other applications, like in this clock experiment.

For their demonstration, the researchers used strontium atoms for the ease in generating remote entanglement. They plan to try this with better clocks such as those that use calcium.

We showed that you can now generate remote entanglement in a practical way. At some point, it might be useful for state-of-the art systems, says Dr. Srinivas.

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Using spooky action at a distance to link atomic clocks - The Hindu

Observing todays world and all conundrums of postmodernism, along with pluralism and the tyranny of choice, one can witness an era of gaps, where great lack of common denominators is a contemporary hazard. The situations redefine diligence and empowers individuals to act like agents of change, not solemnly passive receivers. Now in the era of artificial intelligence, a new underreported challenge has emerged when will humans become obsolete? If one believes that this question is yet another example of philosophical melodrama, it is important to consider that society will soon have to redefine what it considers to be life itself (Bajrektarevi, 2020).

In this article I discuss and investigate the idea of unity and pluralism, inclusion nor integration of EU Members and mostly focus on philosophical and existentialistic constituents of stability in the post-covid era of meaning loss. I specially introduce the triad trust-collaboration- mediation.

Many contemporary reflections on the events of last few decades are surmounting the genuine role of pluralism to unfold democratic standards. Major changes and shifts were induced by general alternations of beliefs, conduct and perception. When our sporadic breakthroughs finally became faster than their infrequent transmissions, this marked a major turning point in the history of human development. Simply put, our civilizations started to significantly differentiate from each other in their respective techno-agrarian, politico-military, ethno-religious, ideological, and economic structures (Bajrektarevi, 2020).

We can bow to the idea of multilateral and plural, dignifying understanding of many different views, aspects, and perceptions. Unquestionably we as humanity are denoting diversity of views or standards alongside our brutal colonial, postcolonial and post war conditions. Pluralism can be an answer, side off totalitarianisms and one-sided approaches. Since everyone is unique from one another, whilst there are infinite differences in humans, our backgrounds, education, and expectation, we must learn to recognize, interlace, and adapt to historic and social-economic context of our fellow beings. We need to question our grounding positioning and reembrace the idea of enlightened argumentation.

Essential question here is, who is managing common denominators of the modern and contemporary pluralisms? Who is translating the gaps of meaning, contexts, and perceptions? To whom we justify our modus operandi? Is there any kind of individual responsibility behind the international clusters and organizations?We do not dispute the idea and practice of pluralism rather searching for unfolded ground, solid in structure and prone to any kind of criticism. But we encounter technological devolvement of human affairs; engendering the idea of biological relativity upholds the question of what life really is. For example, AI now has it all quantum physics, quantum computing, nanorobotics, bioinformatics, and organic tissue tailoring. All of this could eventually lead to a synthesis of all the above into what are usually referred to as xenobots a sort of living robot and biodegradable symbiotic nanorobots that exclusively rely on self-navigable algorithms (Bajrektarevi, 2020).

Pluralism certainly is an ecosystem of democracy, shielding the subtle nuances of partitions, supporting the core, and distinguishing it from the tainted and awry interpretations. The diligence of modern diplomacy faced with conundrum of believes and brown-nosing interests, outdoes the schism, self-regarding positioning, and frictions in the map of human empathy and wisdom.

This is also a reason why diplomats need to respond to cumbersome media in the wake of interpretative realties attacks (e.g. fake news), lukewarmly summoned in social media and e-worlds.

Todays pundits are more likely to study neuroscience, philosophy, and anthropology rather solely art of diplomacy against contemporary labyrinth of possible realities, yielding and era where no mind can encompass it all, rather estimates, prescribes, visions, and predicts. And all we can dwell into is a structure of possible scenarios, relying only on our knowledge, clean perception and trustworthy colleagues, social groups, and intimate circles. And we need to search for common denominators where we suggest one of them.

Trust is a new category not just in contemporary workplaces where we need to create environments of psychological safety to support mutual and successful cooperation. As well it is a genuine link in the chain of negotiating in desultory or hostile environments of contemporary global politics.

Since each international milieu deploys a diverse team of people, reflecting their own culture and believes, we need to be aware of a fragile equilibrium to support strong HR inclusion politics. As definitions says, diversity encompasses the spectrum of infinite dissimilarities that distinguish individuals from one another. Whilst search for common denominator is a big ask, one must conscientiously foster and uphold focus on things that bind, not separate us. Impactful are diverse surroundings we originate and derive from, that can easily put question mark to our cognition, hence to possible misunderstandings: citizenship status, cognitive abilities, cultural differences, education, ethnicity, family, gender, gender expression, geographical location, ideologies, income, language, marital status, morals, neurodiversity, parental status, physical abilities, political beliefs, privilege, race, religious beliefs, skills, social roles, socio-economic status, sexual orientation, upbringing, work experiences etc.

But if we follow the formula of three stated notions, is clear that what we UNDERSTAND, we can ACCEPT; what we FEEL, we can CO-RELATE TO and what we INTERNALIZE, we can CO-CREATE.

In pursuing the goal of collective abundance and stability, leaders sometimes carry to heavy burden. They need to address collective imagination of peoples and create framework of shared reality, identity, bringing together four particulate and individual dimensions: body (healthy living), mind (smart decisions), heart (trustworthy relationships) and spirit (contribution to the benefit of all) and other important cultural beliefs of EU.

While social scientists classically studied trust, conceptualized it as a mental state and measured as such, they were assuming that high levels of trust reflect a social reality in which people are more trustworthy and tend to cooperate more frequently. Only actors who trust one another should cooperate with each other, e.g., exchange information, resources, etc. Of course, reality is relentlessly far away from stated ideal; entering a cooperative relationship normally requires a certain level of trust, and the same is necessary to sustain that relationship. We have accounts of trust as a form of moral commitment, a character disposition, or a dynamic of encapsulated interests, where trust emerges as a mutual co-implication of interests on all transacting parties.

These conceptions turn on a notion of trust as a cognitive category because all depend on assessments of the trustworthiness of the potentially trusted person. (Hardin 2006: 17)

We could estimate that trust emerges as an epiphenomenon of social knowledge: what peoples relationships look like after the fact of cognitive re-appraisals is a sine qua non of the idiom of trust. Can we just bluntly trust, willing to meet all perils of such an irrational decision?

There is more to trust that its relation to cognitive and knowledgeable structures. Trust may be encapsulated in reciprocal expectations (Hardin 2006), but it is also distributed in a variety of human and nonhuman forms; it is as much as cognitive category as it is a material one; indeed, it belongs to the realm of the intersubjective in as much as it belongs to the interobjective. It is as much an anthropological object (of theory) as an object of social knowledge. The question of trust therefore qualifies as an anthropological concept.

In this respect we introduce the TABLES OF TRUST.

TABLE 1.: LEVELS OF TRUST

TABLE 2.: WHOM WE TRUST TO?

TABLE 3.: IN WHAT WE TRUST

TABLE4.: LEVELS OF TRUST / MATERIAL, SPIRITUAL

Collaboration is an old way to work efficiently; at the core of collaboration is trust and exercise of agreed meaning, which can be achievable in many ways, one of which is mediation. Sincerely trust needs to be evident in the relationships how work is done, how words are spoken, and how the results are driven. Without trust, collaboration falls apart quickly and, sometimes, irreparably.

Before entering any sorts of ADRs, one must ask oneself the following introspective questions, regarding ones inner inclination towards trust to be sincere, truthful or the opposite:

TABLE 5: ESSENTIAL QUESTIONS BEFORE ADR

Meanwhile, The Trust Game, designed by Berg et al. (1995) and otherwise called the investment game, is the experiment of choice to measure trust in economic decisions. The experiment is designed to demonstrate that trust is an economic primitive, or that trust is as basic to economic transactions as self-interest (give and get, get, and give). What about higher visons, missions, and inspiration? Of goodness, sacred and beneficial to all? How can we discern the subtle and hidden pivots of status quo or change in the process of mediation for example? How can we set the grounding for effective collaboration in international set up?

We generally expect the role of the mediator is to consist in assisting the parties, finding common ground and business interests that may be explored to settle the dispute through reaching a mutually satisfactory settlement agreement. The mediator is bound to always keep the substance of the mediation confidential. Also, mediators are independent and impartial and may not be involved in any further proceedings involving the case at issue, or any related case. As we know the European Union actively promotes methods of alternative dispute resolution (ADR), such as mediation. The Mediation Directive applies in all EU countries. The Directive concerns mediation in civil and commercial matters. Mediation is at varying stages of development in Member States. The role of the mediator consists of assisting the parties in finding common ground and business interests that may be explored to settle the dispute https://euipo.europa.eu/ohimportal/en/mediation.

So, the mediation as a process needs to be aware of gaps in meaning and trust algorithms described above. The rapid growth of social networks facilitates the exchange of information, whereas malicious behaviours in those ecosystems are also steadily increasing, meanwhile the chances to find correct common denominators vary distinctively. This results in a challenging situation for individuals to trust other parties, mediators or new models and approaches of ADR.

This reflection on pluralism, trust and collaborations shows the propagation of trust within a chain of trust relations.

The precise selection of trustworthy paths as well as the integration of indigenous values, contexts, and inherent plurality of idioms, shows the significant importance of awareness and mindfulness.

What we allocate and are ready to reflect upon or project in comparison to ability to observe with trust and introspection, is pivotal.

Therefore, trust models play a significant role in the context of social, political, and geopolitical trustworthiness. Inferring the trust levels between two unknown parties is a challenging task, specially in the realm of ADR methods, what would certainly be a major and crucial future agenda.

References:

Hardin, Russell (2006): Trust. Cambridge: Polity Press.

Mllering, Guido (2001): The nature of trust: from Georg Simmel to a theory of expectation, interpretationand suspension. Sociology 35(2):403-420.

OHara, Kieron (2004): Trust: from Socrates to spin. Duxford: Icon Books.

ONeill, Onora (2002): A question of trust. The BBC Reith Lectures 2002. Cambridge: Cambridge University Press.

https://euipo.europa.eu/ohimportal/en/mediation

A future filled with empty choices? | New Europe

Prof. Lucija Mulej, Ph.D is an author, columnist, professor and creator of the non-technological innovations (such as her own method: Connectivity of Intelligences 4 Q )

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Of Tyranny Of Choice And The Trust In Pluralistic Societies Analysis - Eurasia Review

This week, scientists will put the finishing touches on the Zetawatt-Equivalent Ultrashort Pulse Laser System (ZEUS) at the University of Michigan, ushering in a new era in high-powered laser experiments, as reported first byNew Atlas.

The device, touted as the most potentlasersystem in the US, will aid researchers in their study of a variety of phenomena, such as quantum physics, space exploration, and cancer therapy.

(Photo : Marcin Szczepanski, Michigan Engineering)

It is worth noting that the ZEUS laser at theUniversity of Michiganwill serve as the replacement for the 0.5-Petawatt Herculeslaser, which was used to set the Guinness World Record for the Highest Intensity Focused Laser in 2008.

ZEUS is built to replicate a beam approximately a million times more powerful than its maximum strength of 3 Petawatts by aiming its laser towards a high-energy electron beam traveling in the opposite direction.

This full power operation of ZEUS will imitate a zetawatt laser pulse, allowing researchers to study extreme plasmas and explore quantum electrodynamics.

The tests could result in the generation of matter and antimatter that could explain the origins of some of the cosmos' most fundamental phenomena.

"Magnetars, which are neutron stars with extremely strong magnetic fields around them, and objects like active galactic nuclei surrounded by very hot plasma - we can recreate the microphysics of hot plasma in extremely strong fields in the laboratory," ZEUS' Associate Director Louise Willingale said in a statement.

But that kind of operation is not anticipated to happen soon since n ewX-rayimaging technologies will be studied first using low-power laser pulses of 30 terawatts, but 500 terawatt experiments are scheduled for the local fall before starting zetawatt operations in 2023, which is referred to as ZEUS's signature experiment.

Read also:Researchers Use Infrared Laser Light to Wirelessly Transmit Power Over 98 Feet of Thin Air!

In addition to helping scientists understand how materials change over very short periods of time, ZEUS is anticipated to contribute to the development of technologies that enhancenuclear weaponsdetection in shipping materials.

The facility's research could potentially result in more compact and effective particle accelerators that produce radioactive isotopes and proton beams, speeding up the creation of cancer treatments.

Karl Krushelnick, director of the Center for Ultrafast Optical Science, which houses ZEUS, said that it would be among the most powerful laser systems in the world and the highest peak power laser in the US.

The high-repetition target area, which conducts tests with more frequent but lower strength laser pulses, is the first target area of the team to start the system's operation.

Franklin Dollar, a graduate of Michigan who is currently an associate professor of physics and astronomy at the University of California Irvine, is the instrument's first user, and his group is investigating a novel form of X-ray imaging.

They will utilize ZEUS to fire infrared laser pulses into a helium gas target, converting the gas to plasma. By accelerating electrons to high energy, this plasma creates very small X-ray bursts as the electron beams flicker, according to scientists.

Related Article:Laser Coffee? Researchers Create A 'Laser-Powered Extractor' That Pumps Out Cold-Brew 300 Times Faster Than Regular Methods!

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Written by Joaquin Victor Tacla

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Scientists Will Activate The 'Most Powerful Laser' in the US Later This Week - Tech Times

With the teaser release of Gehraiyaan earlier this year, the world woke up to the musical genius of Kabeer Kathpalia aka OAFF. Having made his name in the indie music scene for his eclectic atmospheric pop sound and for his ability to lend a theatrical vibe to tracks, the music producer is now tasting mainstream success and rightfully so. Having been following his journey for a while, it is almost unmissable to trace his sonic evolution, his love for music that evokes nostalgia and a need to reinvent and experiment. If there is a music producer to watch out for in this generation, it is him. In a tell-all conversation with Homegrown, OAFF lets us in on his punk rock band days from high school, his love for quantum physics, and creating music.

It is quite known that you were in a punk rock band in high school with Savera and thats what started your musical journey. Was there ever a moment before that when you thought Maybe I want to make music for the rest of my life?

Was there ever a moment before the punk rock band? No, I dont think that moment came even during the punk rock band. It was mostly to be cool in school and impress girls. It was only after that I got into learning music theory because I picked up the guitar for the band. I used to sing before and then I realised I should probably hold something so I picked up the guitar. It wasnt until many many many years later that I thought that this could be a career option. I actually wanted to become a physicist. (Oh thats on quite the opposite end of what you ended up doing) yeah, it worked out that way but in an alternate lifetime maybe I would have done that.

We listen to very different music growing up, whats the kind of music you grew up listening to? What were some of your favourites?

I think I was lucky, in the sense that my family was interested in different kinds of music and I remember waking up, we had this speaker at home when I was a child and there used to be music playing. My father would put something. There was a lot of Indian classical, a lot eclectic Western classical, Philip Glass and stuff like that and then there was the Beatles and Simon and Garfunkel and stuff like that. I remember now and I think now that it left a big impression on me, there used to be this record label called Wildermin records which was this small record label that started there and my father used to collect these CDs cause he liked the artwork when he was younger. He had these CDs and they were these ambient-y kind of very soothing music. And I think a lot of it, (not consciously) stayed in my music-making process. Somehow it has crept in.

In the playlist you shared in an interview, your playlist seems to be dominated by an indie folk sound one that has an atmospheric and cinematic feel to it. Whats your favourite album of all time? And do you feel like its impacted the way you create music?

I feel like that Bon Iver album, which was his second album Bon Iver, Bon Iver. Then theres an album called Dive, its Tychos album. Theres an Asian ambi-electronic producer, I remember that one song, called Walk in the Hills. Even now when I listen to it, it just feels like its been years and years and its the one song I played throughout. Ive been listening to it and I still love it. It was really interesting how he created this cinematic, atmospheric environment using a lot of sounds that are kind of going through some distortion or sounds that are going through a tape effect. So I got really fascinated by how you make things sound old also.

So, basically what youre essentially saying is this the theres this imperfect sound that you feel drawn to?

Yeah. I think that is it, because in both of these Bon Iver albums and with the other producer, theres this like really human element to it. I dont know how much of that translates to my music because I dont know if I do that, but I love listening to that. At least I feel like then theres honesty in the music.

Youve coined the phrase atmospheric pop to describe the kind of music you create. Have you felt a sort of evolution in the kind of music youve been making? Do you feel like youve come into yourself sonically?

Thats a difficult question because I dont like to think this is who I am, but as you change your interests change and youre like, Oh wait, maybe thats just who I was at that point or an aspect to me.

But there are these other things that I havent explored that I want to explore. So more than trying to decide who I am and trying to discover that solely for me, its more fun to kind of explore things that are new and exciting for me. So whether people think thats my sound or some different sound. For me, I think the only way to make music is if Im excited about what Im doing and that constantly changes with new music that Im listening to.

Whats one genre youre excited about experimenting with?

A bunch of stuff. Firstly it was new for me to make music in Hindi. Its not a new genre or anything but it is a new experience for me because the first Hindi song I made was with Kayan, who is a really amazing independent artist. Then I did Gehraiyaan and thats opened up a whole new world to me. Im listening to so many new artists that I didnt listen to before. Recently Ive been listening to bedroom-produced indie pop, which has guitars in it and like badly recorded drums, but like, its kind of cool. I like that vibe.

Do you think its an exciting time to be in the music industry? Especially with people moving away from the perception of needing a studio space to create music to artists creating music from with their laptops in the four walls of their homes.

So the interesting thing is that all the music of Gehraiyaan was made on this laptop that Im having this Zoom call on. It was literally on this one laptop that the songs Doobey and Gehraiyaan, the main title track were made and then later in the studio we finished them. But a lot of it happened at home like a bedroom producer. So I really dont believe this thing about people needing super fancy studios and equipment to make music. I do feel like its always fun to have a new instrument because thats inspiring. Thats a different thing, but youre not limited because your laptop has enough to make whatever you want if you can figure it out. So I feel like a lot of these artists are coming up that are doing this. I feel like the next generation is going to be even far more removed and just be recording via their phones, but theyll be connected to those sounds in a different way.

From an indie music space to seeing commercial success in Gehraiyaan, whats that journey been like? Has it in any way changed the way you create music? What was the creative process for Gehraiyaan like?

I mean, first of all, I wish I knew what that process is. It can be anything at any point in time and you dont really know it. You think that you have a structure, but usually, the good things happen somewhere else. Its not really in that formula or its not in that design that you had. So, the process pretty much stays the same, except that now a few more people are involved in the process. I feel like Im just learning more and more about music and what makes good music good. So thats, whats changed. I dont think the process itself has changed.

What do you think has been your personal favorite project till date?

Personally, I feel Gehraiyaan. I cant say anything except that at this point because it has changed so much for me in terms of not just music, but life, like things change after that. After having a movie like that and having songs that people like so much, every song is special, but Gehraiyaan made a big difference in my life for sure.

How did Gehraiyaan happen to you in that sense?

Shakun Batra, the director reached out to me on Instagram saying he likes my music and if we could meet. We met and he was interested. He had heard some of my independent music and wanted my sound to be the sound of the background score. Then they offered us a song asking Do you guys wanna give it a shot? So we gave it a shot, then there was a long waiting period but finally, that song got approved. Then we were offered one more song, then that got approved and then they were like, Just do the whole album.

Thats very interesting. You started from one song and ended up doing the entire thing.

We werent even supposed to do the song. We were supposed to do the score. And we were like Wow! Were getting to do a score where he wants us to do what we do anyway and then it became like full-fledged songs.

Whats been the most joyous part of creating music for you?

The joyous part is always that moment when youre creating something that initial first time youre sitting on the computer or whatever instrument and you come up with something new and that excites you. Thats amazing. Like thats the feeling that everybody chases.

Who is Kabeer as a person, when removed from the artist?

I dont think Im too different from what I put up on. Like what people see of me, Im pretty similar to that because I think itll be harder to be someone else and to have this artist persona and then go back to living your normal life. I find that has more effort involved than just being whoever you are. But one thing that people might not know is that Im a bit of an obsessive person. Im a nerd, a geek where if theres something that interests me, physics, for example, then I want to really know everything about it and Im consumed by it. So I feel like that happens to me every once in a while about some new topic. And then I need to know everything about it.

Whats the latest obsession at the moment then?

Quantum physics. I started that in college and I started physics in college in my bachelors and then I didnt study physics because I got into music. So I always had this fascination of understanding how the universe works. What is it all about? What are we made of? What is happening? What is the nature of reality? So, Im getting back to studying those things again a little more seriously.

What defines OAFF as an artist?

I think its a constant process of experimentation trying new things and a sense of wonder for me as an artist. That is the feeling that Im always gravitating towards, this sort of bittersweet feeling, which is happy but when its over you feel sad about it. Its almost like nostalgia. I think thats what I really gravitate towards. I think its such a beautiful feeling. Even TV shows or books or songs, the ones which are kind of sad, but really beautiful. I think thats what I love a lot. I think its got to do with trying to remember your childhood or remembering an old memory. Theres something about that is very beautiful to me.

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Inside The Inimitable Atmospheric Pop World Of OAFF - Homegrown

The Standard Model of physics is the theory of particles, fields and the fundamental forces that govern them.

It tells us about how families of elementary particles group together to form larger composite particles, and how one particle can interact with another, and how particles respond to the fundamental forces of nature. It has made successful predictions such as the existence of the Higgs boson, and acts as the cornerstone for theoretical physics.

One way to think about the Standard Model is as a family tree for particles. For example, the Standard Model tells us how the atoms that make up our bodies are made of protons and neutrons, which in turn are made of elementary particles called quarks.

Related: What are bosons?

Keith Cooper is a freelance science journalist and editor in the United Kingdom, and has a degree in physics and astrophysics from the University of Manchester. He's the author of "The Contact Paradox: Challenging Our Assumptions in the Search for Extraterrestrial Intelligence" (Bloomsbury Sigma, 2020) and has written articles on astronomy, space, physics and astrobiology for a multitude of magazines and websites.

The Standard Model is considered by physicists, such as Glenn Starkman at Case Western Reserve University, as one of the most successful scientific theories (opens in new tab) of all time, but on the flip-side, scientists have also recognized that it is incomplete, in the same way that Isaac Newton's theory of universal gravitation derived from his laws of motion, while remarkably successful, was not the whole picture and required Albert Einstein's General Theory of Relativity to fill in the missing gaps.

The Standard Model was drawn together in the 1960s and early 1970s from the work of a cadre of pioneering scientists, but in truth its origins extend back almost 100 years earlier. By the 1880s, it was becoming apparent that there were positively and negatively charged particles produced when gasses are ionized, and that these particles must be smaller than atoms, which were the smallest known structures at the time. The first subatomic particle to be identified, in cathode rays (opens in new tab), was the negative electron in 1897 by the British physicist and subsequent Nobel Prize winner, J. J. Thomson (opens in new tab).

Then, in 1911, Hans Geiger and Ernest Madsen, under the supervision of the Nobel Laureate Ernest Rutherford (opens in new tab) at the University of Manchester, performed their famous 'gold foil' experiment, in which alpha particles (helium nuclei) were fired at a thin gold foil. Some of the alpha particles passed right through the atoms in the foil, while others were scattered left and right and a small fraction bounced right back.

Rutherford interpreted this as meaning that atoms contained a lot of empty space that the alpha particles were passing through, but that their positive charge was concentrated in a nucleus at their center, and on the occasions an alpha particle hit this nucleus dead on, it was scattered. Further experimentation by Rutherford in 191920 found that an alpha particle fired into air could knock a positively charged particle out of a nitrogen atom in the air, turning it into carbon in the process. That particle was the proton (opens in new tab), which gives the atomic nucleus its positive charge. The proton's neutrally charged partner, the neutron, was identified in 1932 by James Chadwick (opens in new tab) at Cambridge, who also won the Nobel Prize.

So, the picture of particle physics in the early 1930s seemed relatively straightforward atoms were made of two kinds of 'nucleons', in the guise of protons and neutrons, and electrons orbited them.

But things were already quickly starting to become more complicated. The existence of the photon was already known, so technically that was a fourth particle. In 1932 the American physicist Carl Anderson discovered the positron (opens in new tab), which is the antimatter equivalent of an electron. The muon was identified in 1936 by Anderson and Seth Neddermeyer (opens in new tab), and then the pion was discovered in 1947 (opens in new tab) by Cecil Powell. By the 1960s, with the advent of fledgling particle accelerators, hundreds of particles were being discovered, and the scientific picture was becoming very complicated indeed. Scientists needed a way of organizing and streamlining it all, and their answer to this was to create the Standard Model, which is the crowning glory of the cumulative work of the physics community of that era.

According to the Standard Model, there are three families of elementary particles. When we say 'elementary', scientists mean particles that cannot be broken down into even smaller particles. These are the smallest particles that together make up every other particle.

The three families are leptons, quarks and bosons. Leptons and quarks are known as Fermions because they have a half-integer spin. Bosons, on the other hand, have a whole-integer spin. What does this mean?

Spin, in the context of quantum physics, refers to spin angular momentum. This is different to orbital angular momentum, which describes Earth's spin around the sun, Earth's spin around its rotational axis, and even the spin of a spinning top. On the other hand, spin angular momentum is a quantum property intrinsic to each particle, even if that particle is stationary. Half-integer spin particles have spin values that are half-integers, so 1/2, 3/2, etc. The bosons have whole integer spin values, eg 1, 2, 3 etc.

Leptons include electrons, muons, tau particles and their associated neutrinos. Quarks are tiny particles that, when joined together, form composite particles such as protons and neutrons. Particles that are made of quarks are called hadrons (hence the Large Hadron Collider), with composite particles formed of odd numbers of quarks, usually three, being called baryons, and those made of two quarks called mesons. Bosons are force carriers they transfer the electromagnetic force (photons), the weak force (Z and W bosons), the strong nuclear force (gluons), and the Higgs force (Higgs boson).

Each 'family' consists of six known particles (except the bosons, which we'll explain later) that come in pairs called 'generations.' The most stable and least massive particles of the family form the first generation. Because of their stability, meaning that they don't decay quickly, all stable matter in the universe is made from first generation elementary particles. For example, protons are formed of two 'up' quarks and one 'down' quark, which are the two most stable quarks.

There are 17 known elementary particles 6 leptons, 6 quarks, but only 5 bosons. There's one force carrier missing the graviton. The Standard Model predicts that gravity should have a force-carrying boson, in the guise of the graviton. Gravitational waves are, in theory, formed from gravitons. However, detecting the graviton will be no mean feat. Gravity is the weakest of the four fundamental forces. You might not think so, after all it keeps your feet on the ground, but when you consider that it takes the entire mass of the planet to generate enough gravity to keep your feet on the ground, you might get a sense that gravity isn't as strong as, say, magnetism can be, which can pick up a paperclip against the gravitational pull of Earth. Consequently, individual gravitons do not interact with matter that easily they are said to have a low cross section of interaction (opens in new tab). Gravitons may have to remain hypothetical for the time being.

As wonderful as the Standard Model is, it describes only a small fraction of the universe. The European Space Agency's Planck spacecraft (opens in new tab) has confirmed that everything that we can see in the cosmos planets, stars and galaxies accounts for just 4.9% of all the mass and energy in the universe (opens in new tab). The rest is dark matter (26.8%) and dark energy (68.3%), the nature of which are completely unknown and which are definitely not predicted by the Standard Model.

That's not all that's unknown. One big question in physics is whether the elementary particles really are elementary, or whether there is hidden physics underlying them. For example, String Theory posits that elementary particles are made from tiny vibrating strings. Then there's the question of antimatter equal amounts of matter and antimatter (opens in new tab) should have been created in the Big Bang, but this would mean we should not be here at all, because all the matter and antimatter should have annihilated each other. Today we see that the universe contains mostly matter, with very little antimatter. Why is there this asymmetry?

Then there's the question of why particles have the masses that they do, and why the forces have the strengths that they have, and why particles are broken down into the three families of leptons, quarks and bosons. That they just are isn't a good enough answer for physicists they want to understand why, and the Standard Model does not tell them.

In an effort to bring the Standard Model up to speed to face these challenges, scientists have introduced the idea of supersymmetry. If true, then supersymmetry would mean that every particle in the Standard Model has a supersymmetric partner with a much greater mass, and a spin that is different by one-half to their Standard Model partners. This would unify fermions with bosons, since the integer-spin fermions would have half-integer-spin super-partners, and the half-integer-spin bosons would have integer-spin super-partners. The least massive and most stable supersymmetry particles would also have no electric charge and interact only very weakly with normal matter, which sounds very much like the properties of dark matter.

Meanwhile, at the very highest energies analogous to those that existed in the first moment after the Big Bang, supersymmetry predicts that the weak force, the strong force and the electromagnetic force would all have the same strength, and essentially be the same force. Scientists call such a concept a 'Grand Unified Theory'.

According to the CERN website, supersymmetry could also help explain the surprisingly small mass of the Higgs boson (opens in new tab), which is 125 GeV (125 billion electronvolts). While this is relatively high, it is not as high as expected. The existence of extremely massive supersymmetric partners would balance things out. And they must be extremely massive, because the Large Hadron Collider (LHC), nor any other particle accelerator before it, has found any evidence for the existence of supersymmetric partners so far, leading some scientists to doubt that supersymmetry is real. If supersymmetric particles exist, then they must be more massive than the LHC can detect; for example, the mass of the gluino (opens in new tab), which is the supersymmetric partner of the gluon that mediates the strong force binding quarks together inside protons and neutrons, has been ruled out up to 2 trillion eV.

So supersymmetry is in danger and physicists are now scrambling to find a replacement theory that can advance upon the Standard Model and explain the Higgs boson's mass, as well as dark matter, Grand Unified Theories and everything else. There are no strong candidates to replace supersymmetry yet, and supersymmetry may still win out, but for now physicists will have to make do with the imperfect world of the Standard Model.

CERN's website (opens in new tab) features more information about the Standard Model.

The U.S. Department of Energy explains the Standard Model (opens in new tab) on their own site.

The Institute of Physics also describes the Standard Model (opens in new tab) on their website.

Follow Keith Cooper on Twitter @21stCenturySETI (opens in new tab). Follow us on Twitter @Spacedotcom (opens in new tab) and on Facebook (opens in new tab).

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What is the standard model? - Space.com

In a laboratory in Kyoto, Japan, researchers are working on some very cool experiments. A team of scientists from Kyoto University and Rice University in Houston, Texas has cooled matter to within a billionth of a degree of absolute zero (the temperature when all motion stops), making it the coldest matter in the entire universe. The study was published in the September issue of Nature Physics, and opens a portal to an unexplored realm of quantum magnetism, according to Rice University.

Unless an alien civilization is doing experiments like these right now, anytime this experiment is running at Kyoto University it is making the coldest fermions in the universe, said Rice University professor Kaden Hazzard, corresponding theory author of the study, and member of the Rice Quantum Initiative, in a press release. Fermions are not rare particles. They include things like electrons and are one of two types of particles that all matter is made of.

The Kyoto team led by study author Yoshiro Takahashi used lasers to cool the fermions (or particles like protons, neutrons, and electrons whose spin quantum number is an odd half integer like 1/2 or 3/2) of ytterbium atoms to within about one-billionth of a degree of absolute zero. Thats roughly 3 billion times colder than interstellar space. This area of space is still warmed by the cosmic microwave background (CMB), or the afterglow of radiation from the Big Bang about 13.7 billion years ago. The coldest known region of space is the Boomerang Nebula, which has a temperature of one degree above absolute zero and is 3,000 light-years from Earth.

[Related: How the most distant object ever made by humans is spending its dying days.]

Just like electrons and photons, atoms are are subject to the laws of quantum dynamics, but their quantum behaviors only become noticeable when they are cooled to within a fraction of a degree of absolute zero. Lasers have been used for more than 25 years to cool atoms to study the quantum properties of ultracold atoms.

The payoff of getting this cold is that the physics really changes, Hazzard said. The physics starts to become more quantum mechanical, and it lets you see new phenomena.

In this experiment, lasers were used to to cool the matter by stopping the movements of 300,000 ytterbium atoms within an optical lattice. It simulates the Hubbard model, a quantum physics first proposed by theoretical physicist John Hubbard in 1963. Physicists use Hubbard models to investigate the magnetic and superconducting behavior of materials, especially those where interactions between electrons produce collective behavior,

This model allows for atoms to show off their unusual quantum properties, which include the collective behavior between electrons (a bit like a group of fans performing the wave at a football or soccer game) and superconduction, or an objects ability to conduct electricity without losing energy.

The thermometer they use in Kyoto is one of the important things provided by our theory, said Hazzard. Comparing their measurements to our calculations, we can determine the temperature. The record-setting temperature is achieved thanks to fun new physics that has to do with the very high symmetry of the system.

[Related: Chicago now has a 124-mile quantum network. This is what its for.]

The Hubbard model simulated in Kyoto has special symmetry known as SU(N). The SU stands for special unitary group, which is a mathematical way of describing the symmetry. The N denotes the possible spin states of particles within the model.

The greater the value of N, the greater the models symmetry and the complexity of magnetic behaviors it describes. Ytterbium atoms have six possible spin states, and the simulator in Kyoto is the first to reveal magnetic correlations in an SU(6) Hubbard model. These types of calculations are impossible to calculate on a computer, according to the study.

Thats the real reason to do this experiment, Hazzard said. Because were dying to know the physics of this SU(N) Hubbard model.

Graduate student in Hazzards research group and study co-author Eduardo Ibarra-Garca-Padilla added that the Hubbard model aims to capture the very basic ingredients needed for what makes a solid material a metal, insulator, magnet, or superconductor. One of the fascinating questions that experiments can explore is the role of symmetry, said Ibarra-Garca-Padilla. To have the capability to engineer it in a laboratory is extraordinary. If we can understand this, it may guide us to making real materials with new, desired properties.

The team is currently working on developing the first tools capable of measuring the behavior that arises a billionth of a degree above absolute zero.

These systems are pretty exotic and special, but the hope is that by studying and understanding them, we can identify the key ingredients that need to be there in real materials, conculed Hazzard.

Originally posted here:

Scientists used lasers to make the coldest matter in the universe - Popular Science

If you're a fan of ambitious new TV shows based on genre classics you know and love, then the fading days of summer are turning out to be an especially sweet time to tune in. HBO is rekindling that Game of Thrones smolder with House of the Dragon, Amazon is tapping J.R.R. Tolkien with The Lord of the Rings: The Rings of Power, and even as we speak, NBC is putting the final touches on an all-new Imaging Chamber for the hugely hyped series launch of the freshly-revived Quantum Leap.

By the time Quantum Leap skips back to the airwaves with its Sept. 19 debut, all the above-mentioned awesomeness will have arrived in the span of just a single month which is pretty mind-boggling, when you think about it. But before the excitement fades our brain, its probably a good idea to take a deep breath and break down just what we really do know about NBCs new adventures in time travel.

This ones easy: NBC describes the new Quantum Leap as a sequel series thats set 30 years after the original show. Expect a mix of new storylines, as well as a tug or two at threads that the original left dangling: Fans of the original Quantum Leap are in for a few surprises, including the return of some original characters and the continuation of the most popular plot points, the network teases.

If youre a fan of the original series, feel free to skip ahead: This section covers the basics of the old-school Quantum Leap you know, the big-picture stuff about the shows premise and setting that should still apply in its new 2022 incarnation.

Both the original Quantum Leap and NBCs new series are sci-fi shows set in their respective present-day, real-world trappings. Theyre based on the idea that technologys just a little farther ahead than we think it isespecially if youve got the governments super-secret science resources at your disposal.

In both series, the key hero is an accomplished physicist who leaps through spacetime into different eras from humanitys past, courtesy of Project Quantum Leap an insanely sophisticated (and expensive) R&D program tucked away in a remote, hush-hush lab. Scott Bakula played the now-iconic role of Dr. Sam Beckett in the original series as the hero who gets himself stuck in an unending sequence of time leaps. In the new show, the stranded-hero honors fall to new star Raymond Lee in the role of physicist Dr. Ben Song.

Time travel isnt the only big twist, though: For one thing, the leaper in each series, wellthey sort of, kind of go rogue to make their initial jump in the first place. Thats a polite way of saying that the government in no way, shape, or form gave them permission to take its fancy particle machine for a free spin, and losing a star scientist to the invisible ether of spacetime leaves the projects suit-wearing overseers with plenty of stern questions (and probably a touch of high blood pressure).

For another thing, theres no way to control (or even predict) where in humanitys past Project Quantum Leap will spit our hero out, as original series scientist Dr. Sam Beckett learned the hard way in the shows very first 1989 episode. If thats not enough, our hero doesnt even get to inhabit their own flesh and blood once theyve made the jump: Instead, they emerge in the body of a completely different person native to the particular time and place where their latest leap has taken them.

Most importantly, theres no known escape at least, not one that Project Quantum Leap has the advanced technology to devise. Taking that first-episode time dive sets off an endless cycle of leap after leap, with the only real reprieve coming not by going home to the present but to another place (and another body) where the entire process resets while our hero waitsyou guessed it, for the next leap.

In order to even do that, theyve got to identify and solve some kind of pivotal problem unique to their temporary human host one that typically changes the course of that persons life for the better. When that key quandary has finally been fixed, the mysteries of physics kick in and its off to another new time and another new host.

Thankfully, Quantum Leap offers its stranded, time-drifting scientist one emotional lifeline that preserves their ties to the home they know and love. Thanks to a sweet piece of lab tech known as the Imaging Chamber, a human back in our own time is able to see and talk to the leaper via holographic image. In the original series, that honor went to Sam Becketts friend Al Calavicci(the late Dean Stockwell), a colorful character whom only Sam could see and hear (a twist that served up endless opportunities for cool plot twists and tons of comic relief). NBCs new Quantum Leap similarly features a new holographic companion characterbut well get to that in a moment.

Though the cast and characters are new, the upcoming Quantum Leap bears a lot of the same creative DNA that made the original such a 1990s sci-fi favorite. Original show creator Donald P. Bellisario is on board as an executive producer alongside Quantum Leap veteran Deborah Pratt, both of whom were producers on the earlier series (Pratt also voiced the old-school supercomputer Ziggy.)

Heres a quick look at the shows main characters, as well as the actors wholl be playing them:

Raymond Lee as Dr. Ben SongRaymond Lee (Kevin Can F**k Himself) takes center stage as the new series time-leaping scientist Dr. Ben Song, a highly-intelligent quantum physicist who jumps through time to explore the mysteries of the original Quantum Leap experiment, via NBC. While Ben will have the help of the Quantum Leap team, it is up to Ben to finally put things in order after the chaotic events of the original experiment.

Ernie Hudson as Herbert Magic Williams Those poking, prodding government types we mentioned earlier? Theyll be represented in the person of Herbert Magic Williams, played in the new show by Ghostbusters alum Ernie Hudson. Every science fiction story needs an authoritarian figurehead, explains NBC, describing Magic as the leader of the Quantum Leap project, torn between the responsibility of answering to his bosses in the Pentagon or taking care of the Quantum Leap team. Old school fans might also remember the character from one of Sam's leaps during the original series.

Nanrisa Lee as Jenn Chou Working closely alongside Magic will be Jenn Choi (Bosch and Star Trek: Picard alum Nanrisa Lee). Jenn is the head of digital security for the Quantum Leap project, and shes focused on discovering why Ben decided to leap in the first place, according to the networkall in the hope of eventually bringing Ben home.

Mason Alexander Park as Ian Wright As Ian Wright, Mason Alexander Park (The Sandman, Cowboy Bebop) isnt just your typical research project egghead, but the computer whiz responsible for bringing Ziggy out of the 20th Century and into the present day. The projects lead programmer, Ian rebuilds the originals shows Pratt-voiced AI, a bot that provides crucial information about Ben's leaps through time, NBC teases.

Caitlin Bassett as Addison Augustine Last but definitely not least is the character wholl serve as Dr. Songs holographic pal the same position held by Al (Dean Stockwell) in the original series. Addison Augustine (TV newcomer Caitlin Bassett) is an ex-Army intelligence officer who has an important role in the Quantum Leap project, NBC explains, showing up amid Bens travels as a hologram that only he can can see. Like Al before her, Addison will dish up valuable insight into the past that Ben uses as a guide throughout his adventures.

Rounding out the rest of the creative team, the new series is written and executive produced by Steven Lilien and Bryan Wynbrandt, with Bellisario, Pratt, and Martin Gero (Stargate Atlantis, Blindspot) teaming up with Dean Georgaris (Life of Pi, The Meg) as executive producers. Gero will also reportedly serve as showrunner, via Deadline.

The short answer? No, but it always helps! This article outlines the shows premise in strokes broad enough to get any viewer started, though the new Quantum Leap, like its predecessor, will have you oriented in no time even if the dog happened to eat your TV-history homework. But if you really want to go into the new show fully prepared, hit up Peacock, where all five seasons of the original series are streaming round the clock. Pressed for time? Its okay to cheat! Heres our handy crash-course lineup of the five most essential Quantum Leap episodes.

NBC is the place to be to catch all new Quantum Leap episodes as they air. The series premiere is set for 10 p.m. ET on Monday, Sept. 19 (immediately following The Voice), with new episodes arriving weekly through the fall season. If you miss one, theres no need to get your feathers in a ruffle: Peacock has your back with day-after streaming on demand for every episode.

Continue reading here:

Everything to know about the new 'Quantum Leap': Where to watch? What's the story? Who returns? - Syfy

The HERMES experiment A Personal Story, by Richard Milner and Erhard Steffens, World Scientific

One hundred years ago, Otto Stern and Walther Gerlach performed their ground-breaking experiment shooting silver atoms through an inhomogeneous magnetic field, separating them according to their spatially quantised angular momentum. It was a clear victory of quantum theory over the still widely used classical picture of the atom. The results also paved the way to the introduction of the concept of spin, an intrinsic angular momentum, as an inherent property of subatomic particles.

The idea of spin was met with plenty of scepticism. Abraham Pais noted in his book George Uhlenbeck and the Discovery of Electron Spin that Ralph Kronig finishing his PhD at Columbia University in 1925 and travelling through Europe, introduced the idea to Heisenberg and Pauli, who dryly commented that it is indeed very clever but of course has nothing to do with reality. Feeling ridiculed, Kronig dropped the idea. A few months later, still against strong resistance by established experts but this time with sufficient backing by their mentor Paul Ehrenfest, Leiden graduate-students George Uhlenbeck and Samuel Goudsmit published their seminal Nature paper on the spinning electron. In the future I shall trust my own judgement more and that of others less, wrote Kronig in a letter to Hendrik Kramers in March 1926.

Spin quickly became a cornerstone of 20th-century physics. Related works of paramount importance were Paulis exclusion principle and Diracs description of relativistic spin-1/2 particles, as well as the spin-statistics theorems (namely the FermiDirac and BoseEinstein distributions for identical half-integerspin and integerspin particles, respectively). But more than half a century after its introduction, spin re-emerged as a puzzle. By then, a rather robust theoretical framework, the Standard Model, had been established within which many precision calculations became a comfortable standard. It could have been all that simple: since the proton consists of two valence-up and one valence-down quarks, with spin up and down (i.e. parallel and antiparallel to the protons spin, respectively), the origin of its spin is easily explained. The problem dubbed spin crisis arose in the late 1980s, when the European Muon Collaboration at CERN found that the contribution of quarks to the proton spin was consistent with zero, within the then still-large uncertainties, and that the so-called EllisJaffe sum rule ultimately not fundamental but model-dependent was badly violated. What had been missed?

Today, after decades of intense experimental and theoretical work, our picture of the proton and its spin emerging from high-energy interactions has changed substantially. The role of gluons both in unpolarised and polarised protons is non-trivial. More importantly, transverse degrees of freedom, both in position and momentum space, and the corresponding role of orbital angular momentum, have become essential ingredients in the modern description of the proton structure. This description goes beyond the picture of collinearly moving partons encapsulated by the fraction of the parent protons momentum and the scale at which they are probed; numerous effects, unexplainable in the simple picture, have now become theoretically accessible.

The HERMES experiment at DESY, which operated between 1995 and 2007, has been a pioneer in unravelling the mysteries of the proton spin, and the experiment is the protagonist in a new book by Richard Milner and Erhard Steffens, two veterans in this field as well as the driving forces behind HERMES. The subtitle and preface clarify that this is a personal account and recollection of the history of HERMES, from an emergent idea on both sides of the Atlantic to a nascent collaboration and experiment, and finally as an extremely successful addition to the physics programme of HERA (the worlds only leptonproton collider, which started running at DESY 30 years ago for one and a half decades).

Milner and Steffens are both experts on polarised gas targets, with complementary backgrounds leading to rather different perspectives. Indeed, HERMES was independently developed within a North American initiative, in which Milner was the driving force, and a European initiative around the Heidelberg MPI-K led by Klaus Rith, with Erhard Steffens as a long-time senior group member. In 1988 two independent letters of intent submitted to DESY triggered sufficient interest in the idea of a fixed-target experiment with a polarised gas target internal to the HERA lepton ring; the proponents were subsequently urged to collaborate in submitting a common proposal. In the meantime, HERMES feasibility needed to be demonstrated. A sufficiently high lepton-polarisation had to be established, as well as smooth running of a polarised gas target in the harsh HERA environment without disturbing the machine and the main HERA experiments H1 and Zeus.

By summer 1993, HERMES was fully approved, and in 1995 the data taking started with polarised 3He. The subsequently used target of polarised hydrogen or deuterium employed the same concepts that Stern and Gerlach had already used in their famous experiment. The next decade saw several upgrades and additions to the physics programme, and data taking continued until summer 2007. In all those years, the backbone of HERMES was an intense and polarised lepton beam that traversed a target of pure gas in a storage cell, highly polarised or unpolarised, avoiding extensive and in parts model-dependent corrections. This constellation was combined with a detector that, from the very beginning, was designed to not only detect the scattered leptons but also the spray produced in coincidence. These features allowed a diverse set of processes to be studied, leading to numerous pioneering measurements and insights that motivated, and continue to motivate, new experimental programmes around the world, including some at CERN.

Richard Milner and Erhard Steffens provide extensive insights, in particular into the historic aspects of HERMES, which are difficult to obtain elsewhere. The book gives an insightful discussion of the installation of the experiment and of the outstanding efforts of a group of highly motivated and dedicated individuals who worked too often in complete ignorance of (or in defiance of) standard working hours. Their account enthrals the reader with vivid anecdotes, surprising twists and personal stories, all told in a colloquial style. While clearly not meant as a textbook indeed, one might notice small mistakes and inconsistencies in a few places this book makes for worthwhile and enjoyable reading, not only for people familiar with the subject but equally for outsiders. In particular, younger generations of physicists working in large-scale collaborations might be surprised to learn that it needs only a small group and little time to start an experiment that goes on to have a tremendous impact on our understanding of natures basic constituents.

The rest is here:

Hymn to HERMES CERN Courier - CERN Courier

Quantum theory is perhaps the most successful scientific idea ever. So far, it has never been proved wrong. It is stupendously predictive, it has clarified the structure of the periodic table, the functioning of the sun, the colour of the sky, the nature of chemical bonds, the formation of galaxies and much more. The technologies we have been able to build as a result range from computers to lasers to medical instruments.

Yet, a century after its birth, something remains deeply puzzling about quantum theory. Unlike its illustrious predecessor, Newtons classical mechanics, it does not tell us how physical systems behave. Instead, it confines itself to predicting the probability that a physical system will affect us in one way or another. When an electron is fired from one side of a wall with two holes, for instance, quantum theory tells us where it will end up on the other side, stubbornly saying nothing plausible about which hole it has gone through. It treats any physical system as a black box: if you do this to it now, it will react like that later. What happens in between? The theory simply doesnt tell us.

Many scientists are content with this, but others are puzzled. Among the latter, some make hypotheses: they propose complicated stories about parts of nature that are hidden from us for ever, or multiple universes that underpin the part of reality we do see. Others resign themselves to the notion that science is not about what things really are: it is only about what we are able to directly observe.

Another idea has recently begun to catch on. Perhaps there is no need to make anything up about what lies behind quantum theory. Perhaps it really does reveal to us the deep structure of reality, where a property is no more than something that affects something else. Perhaps this is precisely what properties are: the effects of interactions. A good scientific theory, then, should not be about how things are, or what they do: it should be about how they affect one another.

The idea seems radical. It pushes us to rethink reality in terms of relations instead of objects, entities or substances. The possibility that this could be what quantum physics is telling us about nature was first suggested a quarter of a century ago. For a while it remained largely unnoticed, then several major philosophers picked it up and began to discuss it. Nowadays interest in the idea, called the Relational Interpretation of Quantum Mechanics, is steadily growing. It is a possible solution to the puzzle of quantum theory: what quantum phenomena are is evidence that all properties are relational.

There is a strikingly similar definition of existence at the root of the western philosophical tradition. Platos The Sophist contains the following phrase: Anything which possesses any sort of power to affect another, or to be affected by another, if only for a single moment, however trifling the cause and however slight the effect, has real existence; and I hold that the definition of being is simply action. [] And in the eastern tradition, the Buddhist philosopher Ngrjunas central notion of emptiness (nyat) tells us that nothing has independent existence: anything that exists, exists thanks to, as a function of, or according to the perspective of, something else.

So maybe this is not such a radical idea after all. We all know that a chemical substance is defined by how it reacts, a biological species is defined according to the niche it occupies in the biosphere, and what defines us as human beings is our relationships. Think of a simple object such as a blue teacup. Its being blue is not a property of the cup alone: colours happen in our brain as a result of the structure of the receptors in the retina of our eyes and as a consequence of the interactions between daylight and the cups surface. Its being a teacup refers to its potential function as a drinking vessel: for an alien who doesnt know about drinking tea, the very notion of a teacup is meaningless. What is more, its stability as an object depends on the timescale in which we consider it: take a longer view and it is just a fleeting aggregation of atoms. And are these atoms themselves independent elements of reality? No they are not, as quantum theory shows: they are defined by their physical interactions with the rest of the world.

So quantum physics may just be the realisation that this ubiquitous relational structure of reality continues all the way down to the elementary physical level. Reality is not a collection of things, its a network of processes.

If this is correct, I think it comes with a lesson. We understand reality better if we think of it in terms of interactions, not individuals. We, as individuals, exist thanks to the interactions we are involved in. This is why, in classic game theory, the winners in the long run are those who collaborate. Too often we foolishly measure success in terms of a single actors fortunes. This is both short-sighted and irrational. It misunderstands the true nature of reality, and is ultimately self-defeating. I believe, for example, that we make this mistake all the time in international politics. Prioritising individual countries, or groups of countries, over the common good, is a catastrophic error. It leads to the devastation of war and prevents us from addressing the true challenges that all of humankind a node in natures network faces as a whole.

Carlo Rovelli is a professor of physics. To support the Guardian and the Observer buy a copy at guardianbookshop.com. Delivery charges may apply.

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Helgoland: Making Sense of the Quantum Revolution by Carlo Rovelli (Allen Lane, 9.34)

The World According to Physics by Jim Al-Khalili (Princeton, 12.99)

Theaetetus & Sophist by Plato (Cambridge, 17.99)

Meeting the Universe Halfway: Quantum Physics and the Entanglement of Matter and Meaning by Karen Barad (Duke, 23.99)

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The big idea: why relationships are the key to existence - The Guardian

Mayer Hall recognized as the birthplace of density functional theory

(L-R): Dean Boggs, Professor Schuller, Professor Emeritus Sham and Executive Vice Chancellor Simmons hold the plaque commemorating Mayer Hall as a historic landmark. Photos by: Daniel Orren / UC San Diego Health.

Is there magic in the walls of Mayer Hall? This is the question Oleg Shpyrko, chair of the Department of Physics at the University of California San Diego, asked the audience gathered in the auditorium for a daylong series of events to celebrate the buildings designation as a historical site by the American Physical Society (APS).

Mayer Hall, after all, was named after famed theoretical physicist Maria Goeppert Mayerthe second woman ever to win the Nobel Prize in physics. It was also the birthplace of metamaterials which, among other things, have been used to create Harry Potter-like invisibility cloaks. In the labs of Mayer Hall, many novel high-temperature superconductors and quantum materials were developed. It was also in Mayer Hall where Walter Kohn and Lu Jeu Sham created the Kohn-Sham equation as part of their work in establishing density functional theory, or DFT.

Shpyrko concluded that, no, there wasnt magic inside the walls of Mayer Hall, but there was magic in the people who worked there.

And there was magic in the pivotal Kohn-Sham equation. Its subsequent impact on everything from new materials design to drug discovery led APS to designate Mayer Hall a historical site, stating that DFT is the most used technique for calculating the properties of nuclei, molecules, polymers, macromolecules, surfaces and bulk materials in the chemical, biological and physical sciences.

In the early part of the 20th century, the development of quantum mechanics allowed physicists to learn about the properties and behavior of atoms. Traditionally, the Schrdinger equation was used to determine the probabilistic location and behavior of a particle, including the complexity associated with quantum superposition, which is the basis of the famous Schrdingers cat paradox.

As a result, this equation requires a significant amount of computational effort for each individual electron as well as interactions with every other electron and nuclei. Even a single water molecule contains 10 electrons. Thus, determining the electron behavior of larger molecules quickly becomes prohibitive, akin to controlling the behavior of hundreds of quantum-mechanical Schrdingers kittens who are actively interacting with each other while occupying many locations at once.

From 1964-1966, Kohn and Sham laid the foundation of a computation method based on a single-particle approach, which became known as the Kohn-Sham equation and formed the basis of density functional theory.

DFT simplified the previous process by using the density of all the electrons in the system to determine electron behavior. Researchers no longer needed to focus on each individual electron, but used their collective density as the single variable to solve for, transforming the way quantum mechanics research was performed.

DFT is known as an ab initio, or first principle method, because it can predict material properties for unknown systems without any experimental input. So while it does not precisely solve the Schrdinger equation, it does offer a close approximation at a fraction of the computational effort.

Understanding the electronic properties of complex systems is essential to the design and engineering of new materials and drugs. DFT has been used to study and develop the properties of important materials such as novel semiconductors, new catalysts, neuromorphic materials and complex molecules.

For instance, drug discovery uses DFT as a fast and efficient method to limit the number of drugs that must be experimentally tested for their efficacy in the treatment of many diseases. Thanks to DFT, the time and cost of drug development have been considerably reduced.

The UC San Diego School of Physical Sciences and the physics department worked together to create an engaging, informative day of events to celebrate Mayer Halls designation. Although APS officially named Mayer Hall a historic site in 2021, the celebration was postponed until now due to the pandemic.

Distinguished Professor of Physics Ivan Schuller and Shpyrko welcomed attendees before opening the day with a series of lectures on the impacts of DFT. Researchers and experts from around the world provided insight into the ways DFT continues to shape science, engineering and medicine. The talks touched on everything from materials physics and molecular dynamics to drug discovery and supercomputing.

Dean Boggs spoke about the spirit of discovery that exists in the School of Physical Sciences.

We were thrilled to welcome everyone in-person for this event, stated Dean of the School of Physical Sciences Steven E. Boggs. More than just background on DFT itself, these talks highlighted the spirit of discovery that is still present on our campus. The School of Physical Sciences has lived at the heart of that spirit since the universitys founding.

After the lectures and a panel discussion, the university held a dedication ceremony and plaque unveiling. From APS, President Jon Bagger and former President Jim Gates commented on how meaningful the designation was and the continuing importance of DFT.

UC San Diegos Executive Vice Chancellor Elizabeth H. Simmons noted that the groundbreaking work of Kohn, Sham and colleague Pierre Hohenberg was only one example of the extraordinary talent found in the School of Physical Sciences.

The efforts of faculty like Kohn, Sham, Mayer, Roger Tsien, Sally Ride, Harold Urey and others are testament to our universitys remarkable history as a community of visionaries who push boundaries and break barriers to change the world, she said. Their transformative impacts across academic disciplines and in the lives of student and faculty colleagues will continue to reverberate into the future.

Excerpt from:

Honoring a UC San Diego Landmark and Its Lasting Impact on Physics - University of California San Diego