Category Archives: Quantum Physics

Professor Somnath Bhattacharyya next to the vapor deposition chamber that is used to produce diamonds in the lab. Credit: Wits University

The discovery of triplet spin superconductivity in diamonds has the potential to revolutionize the high-tech industry.

Diamonds have a firm foothold in our lexicon. Their many properties often serve as superlatives for quality, clarity, and hardiness. Aside from the popularity of this rare material in ornamental and decorative use, these precious stones are also highly valued in industry where they are used to cut and polish other hard materials and build radiation detectors.

More than a decade ago, a new property was uncovered in diamonds when high concentrations of boron are introduced to it superconductivity. Superconductivity occurs when two electrons with opposite spin form a pair (called a Cooper pair), resulting in the electrical resistance of the material being zero. This means a large supercurrent can flow in the material, bringing with it the potential for advanced technological applications. Yet, little work has been done since to investigate and characterize the nature of a diamonds superconductivity and therefore its potential applications.

New research led by Professor Somnath Bhattacharyya in the Nano-Scale Transport Physics Laboratory (NSTPL) in the School of Physics at the University of the Witwatersrand in Johannesburg, South Africa, details the phenomenon of what is called triplet superconductivity in diamond. Triplet superconductivity occurs when electrons move in a composite spin state rather than as a single pair. This is an extremely rare, yet efficient form of superconductivity that until now has only been known to occur in one or two other materials, and only theoretically in diamonds.

Professor Somnath Bhattacharyya next to a dilution fridge a specialised piece of equipment that enables quantum properties of diamond. Credit: Wits University

In a conventional superconducting material such as aluminum, superconductivity is destroyed by magnetic fields and magnetic impurities, however triplet superconductivity in a diamond can exist even when combined with magnetic materials. This leads to more efficient and multifunctional operation of the material, explains Bhattacharyya.

The teams work has recently been published in an article in the New Journal of Physics, titled Effects of Rashba-spin-orbit coupling on superconducting boron-doped nanocrystalline diamond films: evidence of interfacial triplet superconductivity. This research was done in collaboration with Oxford University (UK) and Diamond Light Source (UK). Through these collaborations, beautiful atomic arrangement of diamond crystals and interfaces that have never been seen before could be visualized, supporting the first claims of triplet superconductivity.

Professor Somnath Bhattacharyya and members of the Wits Nano-Scale Transport Physics Lab. They are Professor Yorick Hardy, Dr Christopher Coleman, Kayleigh Mathieson and Professor Somnath Bhattacharyya. Credit: Wits University

Practical proof of triplet superconductivity in diamonds came with much excitement for Bhattacharyya and his team. We were even working on Christmas day, we were so excited, says Davie Mtsuko. This is something that has never been before been claimed in diamond, adds Christopher Coleman. Both Mtsuko and Coleman are co-authors of the paper.

Despite diamonds reputation as a highly rare and expensive resource, they can be manufactured in a laboratory using a specialized piece of equipment called a vapor deposition chamber. The Wits NSTPL has developed their own plasma deposition chamber which allows them to grow diamonds of a higher than normal quality making them ideal for this kind of advanced research.

This finding expands the potential uses of diamond, which is already well-regarded as a quantum material. All conventional technology is based on semiconductors associated with electron charge. Thus far, we have a decent understanding of how they interact, and how to control them. But when we have control over quantum states such as superconductivity and entanglement, there is a lot more physics to the charge and spin of electrons, and this also comes with new properties, says Bhattacharyya. With the new surge of superconducting materials such as diamond, traditional silicon technology can be replaced by cost effective and low power consumption solutions.

The induction of triplet superconductivity in diamond is important for more than just its potential applications. It speaks to our fundamental understanding of physics. Thus far, triplet superconductivity exists mostly in theory, and our study gives us an opportunity to test these models in a practical way, says Bhattacharyya.

Reference: Effects of Rashba-spinorbit coupling on superconducting boron-doped nanocrystalline diamond films: evidence of interfacial triplet superconductivity by Somnath Bhattacharyya, Davie Mtsuko, Christopher Allen and Christopher Coleman, 14 September 2020, New Journal of Physics.DOI: 10.1088/1367-2630/abafe9

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Diamonds Are a Quantum Scientist's Best Friend: Discovery May Revolutionize the High-Tech Industry - SciTechDaily

LEXINGTON, Ky. (Oct. 20, 2020) Sumit R. Das, the Jack and Linda Gill Professor in the University of Kentucky Department of Physics and Astronomy, is serving as the 2019-20 UK College of Arts and Sciences Distinguished Professor and will deliver the annual Distinguished Professor Lecture next week.

The lecture, titled Deconstructing Space-Time, will be held 7-8 p.m. Thursday, Oct. 29, on Zoom.

Developments in theoretical physics over the past couple of decades have led to a set of ideas that "space" is not a fundamental notion, but arises as an emergent concept from more abstract entities. This view has led to remarkable progress in reconciling the laws of gravity with the principles of quantum mechanics and has shed valuable light on puzzles related to black holes. This talk will discuss the historical origins of some of these ideas and recent results that have enriched our understanding of the fundamental laws of nature.

Das received his bachelor's and master's degrees in physics from the University of Calcuttaand his doctorate from the University of Chicago in 1984. After postdoctoral positions at Fermi National Accelerator Laboratories and California Institute of Technology, he joined the faculty of Tata Institute of Fundamental Research inMumbai in 1987. In 2002 he moved to the University of Kentucky as a full professor. He served as the department chair from 2013 to 2017. Over the years he has held visiting professor positions in several institutions around the world.His research has meandered through several areas of theoretical physics: the theory of strong interactions, string theory, quantum aspects of black holes and aspects of nonequilibrium phenomena. He has published more than 140 research papers, several chapters in books and two encyclopedia articles. He is a recipient of the S.S. Bhatnagar Award and a fellow of the Indian Academy of Sciences.

To register for the lecture, visit https://uky.zoom.us/webinar/register/WN_cqbe095LQg-WrP4kL6IPmA.

Since 1944, the College of Arts and Sciences has recognized the accomplishments of its faculty in the humanities, social sciences, and natural and mathematical sciences, with the Distinguished Professor Award. The award is the highest professional recognition offered by the college and is bestowed on the basis of three criteria: outstanding research, exceptionally effective teaching and distinguished professional service.

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Sumit Das to Deliver 2019-20 A&S Distinguished Professor Lecture on 'Deconstructing Space-Time' - UKNow

In China, I was fascinated by the use of electric scooters everywhere. Students were zipping past me at considerable speed, with tires making the only sound. At night, walking across campus could be a challenge. Like phantoms, people on dark scooters crossed my path unexpectedly, making me jump aside. They were reluctant to turn their lights on because it would use some of the battery power that they needed for travel.

And theres the problem. When you run low on gas, a 5-minute fill-up at a gas station will get you going again for a long time. Electric vehicles require a recharge, and depending on the kind of charger thats used, it can take hours. Batteries for electric cars are improving significantly, though. The latest lithium-ion types provide a range of more than 200 miles.

For those of us who are planning to build their own electric car, there are some choices. One could make do with a 100-mile range, using 14 standard lead-acid batteries. This comes with a substantial amount of weight, although it eliminates the need for a fuel system, exhaust pipes, and a transmission. A high-grade lithium-ion battery will double the range. Prices have been dropping continuously, currently at $156 per kilowatt-hour (kWh) according to Bloomberg New Energy Finance. This means that if you want the latest 68 kWh battery pack like the one used in the 2020 Nissan Leaf Plus, youll still pay $10,000 for that part alone. The engine-less 1971 VW Beetle body I have waiting to be converted into an electric car will probably be more modest. Classic Beetles have traditionally been near-impossible to heat and air-condition anyway, so theres no anticipation of electricity use by those two power-hungry consumers.

A new light on the horizon comes in the form of the quantum battery. This latest invention relies on quantum physics instead of chemical reactions like the current batteries. Essentially, the principle is based on the energy exchange between electrons and photons on the atomic scale. Quantum batteries dont lose power over time. Companies working on this innovation, including Tesla, Panasonic and Toyota, are tight-lipped about details and current status of the project. Dont expect to be able to buy a quantum battery at your local autoparts store soon. But it looks like a new, more powerful option for running electric vehicles may be coming.

Rudi Kiefer, Ph.D., is a professor at Brenau University, teaching physical and health sciences on Brenaus Georgia campuses and in China. His column appears Sundays and at gainesvilletimes.com.

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Column: A new era of electric vehicles could be on the way - Gainesville Times

First the good news. Exclusive News Channels in India, despite the good old DD, started about a quarter of a century ago, but actually came in vogue abut two decades ago. Most were backed by publication houses, some came later, again media people. The better news is that instead of complaints against government gags, tags not entirely honourable as pro establishment channels, or somewhat neutral, were the only adjectives that were entertained. For instance, a popular one by a journalist who could explain the demographics of Indian general electoral trends methodically, took his position. Regional channels are mostly tuned to a respective two- party system of the state, as is the paper media.

The present TRP war, came about to be, considering whether it is really that serious, due to a sudden formation of a new channel by an energetic, intelligent rebel of a journo, who got the right timing to prey upon sitting ducks of scams. It became a one man show with such vehemence, that no government or political spokes persons had enough knowledge or liberty or the solace from their party to reveal beyond a certain quantum.

I, as a neurologist am not an activist, but could see a new talent of delivery, oration, incisive phrases, picking up local but common mans jargon. Not without well worked hand movements now with a single hand the right being bandaged. Decent, too loud, too obsessed with ambition, say what you may. One has to accept that he knows the works-showmanship, choosing topics, aligning and re-aligning a broadcast at will.

With a pardon, that I may not know all rules and trespasses of journalism, one realizes how much behind the scene competition there is in Indian media. Acknowledging the mastery of presentable, pleasant and all covering concept for the publication house, that gave me the opportunity to enlist me as a Blog writer, the presentation on electronic media needs a new change.

Actually, some who went overboard, well versed and long -term entrepreneurs, could have just sat and watched. It was possibly a sudden loss of neve, missing the full thrust on a slower delivery, caught, without crossing the ropes. Probably this new renegade talent, forced too many bouncers and quietly gave a slower one. So, was it a ploy of the grand Republican, to incite a TRP overdoing under his well laid contraptions!

I am not invoking intra-media rivalry, just studying a sudden change of broadcasting. The impact in delivery is being modulated by other channels, that ran on didactic rules of the producer. There is a place of movie directors, script writers, dialogue fillers. Good for the Indian media. Indian channels shall be watched more by NRIs and the western audiences.

As for the content, I stay away from what is good, bad, ethical or otherwise. The news -burger should be well stuffed, veg or non-veg. That is what gives the TRP. In a quiet candle-light upscale restaurant, if the customers have changed to noisy Furtunner/Scorpia/Harrier owners, it may be a nice marketing idea to start serving sizzlers, with a concealed microphone and speaker on the tray, which the waiter can modulate as he takes a circuitous turn to destination table, imagine, how many shall start ordering that one with the noise Even if the stuff is mediocre, modest in value, you are paying for the sound for an eatable!

The TRP, or the target rating point, is a method of measuring the total viewership, that is the viewers and time duration of viewing. Generally done by placing a few thousand meters attached to regular TVs, randomly, but also by representing the users preferences of language, timing of maximum watching, and the viewership pull on ads. The final number is calculated by using the viewers as denominator, the numerator as the total impressions delivered to the target x 100.

As an example, if the viewers are 10, 000, and impressions, 1000 x 100, the TRP is 10. Thereafter begins the baking and frying as per rules! Not discrete to analyse further. By all types of maths including Quantum Physics. Consider that electromagnetic waves can be deviated by a magnetic field. You finally get a sore between 0-3-0! If sliding from a perennial 2. 3 to 2.2 is a calamitous as a rate cut on a assured bond, it might be an issue with mega- investors!

How correct is the TRP to actual viewership? Well this is the best and a universal method followed. The value is the rating of the channel, that impacts the minds towards more viewership, and attracting revenues through ads.

Talking of previous such self- designed programmes, was Rajat Sharmas, Aap ki Adalat. He softly invited every luminary, icon, politician, but not without a few awkward questions. Arun Shouries scam under CM A R Antulay, surely was on paper media but one of the most daring ones.

Tehelka initially a one- time event, where perhaps for the first time concealed electronic devices were used, and later converted into a weekly publication. Had the media and public been so charged then, it had the ingredients of a news channel!

The history of television news broadcasting somewhat begins with David Sarnoff, a young man who joined the most popular network NBC. Those were war days bur Sarnoff had envisioned that the coming of television would be the main thing. Catching up in competition was a smaller company CBS, that had more funds, and even borrowed NBC talent.

Technological hurdles were the availability of a co-axial cable that would run on land. Finally, the task was handed over to part government owned AT&T. Even before the end of the war, Sarnoff had announced, that US shall have its own TV broadcasting, rather than the anticipated Imperial stations.

Funds were always a problem. R J Reynolds, the makers of Camel came to help. They improvised their ow popular programme, Caravans on Camels Went well.

The heave came in the 1948 election convention. Philadelphia was chosen by political parties, as it had the maximum density of cable networks. One case where the presence of broadcast technology influenced political decision. TV sales were on the rise. Sure, there had to be new talent for visual presentations but some old radio voices were kept due their appeal to the audience. Broadcasting had to be tutored. Interest generated by sending teams to broadcast from the site of the incident began.

TRPs is just a symbol of the intense media, competition, as on-coming digitalization has been hurried by Covid.Next shall be cable TV, Computer domestic AI all combined. It is already there.

The wise shall allow, accommodate, modulate the electronic media. India has the worlds largest English -speaking audience. New more riveting methods are seen. The first launch of TV broadcasting by NBC was a political convention. Its the circumstance that gives the opening. Beyond that the road is long and not without struggle!

dil se to har mo.mla kar ke chale the saaf ham,kahne me un ke smne baat badal badal ga.Faiz

(I left clarifying all issues of the heart before the meeting,While clarifying, before her, somehow the issues kept changing)

DISCLAIMER : Views expressed above are the author's own.

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The TRP turf - The Times of India Blog

Any extraterrestrial organisms we find will be made of the same atoms we are, observes Harvards Center for Astrophysics, Avi Loeb, about the recent detection of a potential biosignature in the atmosphere of Venus, the nearest planet to Earth where NASA is currently considering sending a spacecraft.

Microbes may reside there in the Venusian cloud deck 35 miles above ground level, where the temperature and pressure are similar to what they are in the lower atmosphere of Earth, writes Loeb in Scientific American, in droplets at a density that is orders of magnitude smaller than in air on Earth; if so, they could have common ancestry to terrestrial life, given that asteroids occasionally graze the atmospheres of both planets, potentially transferring material from one to the other.

This week, though, three independent studies announced that they have failed to find evidence of phosphine in the Venusian atmosphere, casting doubt on whether the gas could be produced by alien microbes.

Venus The Solar Systems First Habitable Planet

Yet recent research by Yale astronomers suggests that our Moon may harbor clues that Venus described by Stephen Hawking as Earths kissing cousin may have had an Earth-like environment billions of years ago, with water and a thin atmosphere. Their findings follow research suggesting that our sister planet may have been the solar systems first habitable planet.

Clues to Alien Life Billions of Fragments of Venus May Exist on the Moon

Darwins Dice

The possibility of current or past life on Venus raises a hotly debated question of how closely extraterrestrial life would evolve to resemble that on Earth, with some scientists, such as Harvards evolutionary theorist, Stephen Jay Gould, who argued that with a slightly different roll of the Darwinian dice, earth would have been inhabited by creatures unimaginable, while others such as Charles S. Cockell, an astrobiologist at the University of Edinburgh and Director of the UK Center for Astrobiology, conjecture that if there is biology elsewhere in the universe we would find it strikingly familiar down to the carbon-based machinery in its cells. All life is simply living matter, material capable of reproducing and evolving.

Alien Evolution Advanced Life Will Mirror Homo Sapiens

Physics of Life

In his book, The Equations of Life: How Physics Shapes Evolution, Cockell conjectures that the cosmos if populated, would harbor creatures more like like those lined up at Mos Eisleys dimly-lit cantina on the Star Wars planet Tatooine. No matter how different the conditions on distant worlds, suggests Cockell, all life being living matter material capable of reproducing and evolvingis presumably subject to the same laws of physics from quantum mechanics to thermodynamics and the laws of gravity.

Early Earth was covered with carbonaceous material from meteorites and comets that provided the raw materials from which first life emerged. In his book, The Eerie Silence, astrophysicist Paul Davies echoes Harvards Gould suggesting that the original cells would have been able to pick and choose from the early Earths organic cocktail. To the best of our knowledge, he writes, the twenty-one chosen by known life do not constitute a unique set; other choices could have been made, and maybe were made if life started elsewhere many times.

Physics of Alien Life

Biologys Great Mystery

Cockell writes George Johnson for the New York Times, lucidly addresses biologys great mystery: If we grant that life is an interplay of chance and necessity, in the words of the French biochemist Jacques Monod, then which has the upper hand? In a nod to Monod, Cockel argues that even at this deep level, the possibilities of life were tightly circumscribed. Rerun the tape of evolution, and DNA, RNA, ATP, the Krebs cycle the rigmarole of Biology 101 would probably arise again, here or in distant worlds. Single cells would then join together, seeking the advantages of metazoan life, until before you know it something like the earthly menagerie would come to be.

The Daily Galaxy, Jake Burba, via Scientific American and New York Times Science

Image credit: Shutterstock License

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Beyond Homo Sapiens A Slightly Different Roll of the Darwinian Dice (Weekend Feature) - The Daily Galaxy --Great Discoveries Channel

As humans, we take time for granted. Were born into an innate understanding of the passage of events because its essential to our survival. But AI suffers from no such congenital condition. Robots do not understand the concept of time.

State of the art AI systems only understand time as an implicit construct (we program it to output time relevant to a clock) or as an explicit representation of mathematics (we use the time it takes to perform certain calculations to instruct its understanding of the passage of events). But an AI has no way of understanding the concept of time itself as we do.

Time doesnt exist in our classical reality in a physical, tangible form. We can check our watch or look at the sun or try and remember how long its been since we last ate, but those are all just measurements. The actual passage of time, in the physics sense, is less proven.

In fact, scientists have proven that times arrow a bedrock concept related to the classical view of time doesnt really work on quantum computers. Classical physics suffers from a concept called causal asymmetry. Basically, if you throw a bunch of confetti in the air and take a picture when each piece is at its apex, itll be easier for a classical computer to determine what happens next (where the confetti is going) than what happened before (what direction the confetti would travel in going backwards through time).

Quantum computers can perform both calculations with equal ease, thus indicating they do not suffer causal asymmetry. Times arrow is only relevant to classical systems of which the human mind appears to be, though our brains are almost certainly quantum constructs.

Where things get most interesting is if you consider the addition of artificial intelligence into the mix. As mentioned previously, AI doesnt have a classical or quantum understanding of time: time is irrelevant to a machine.

But experts such as Gary Marcus and Ernest Davis believe an understanding of time is essential to the future of AI, especially as it relates to human-level artificial general intelligence (AGI). The duo penned an op-ed for the New York Times where they stated:

In particular, we need to stop building computer systems that merely get better and better at detecting statistical patterns in data sets often using an approach known as deep learning and start building computer systems that from the moment of their assembly innately grasp three basic concepts: time, space and causality.

While the statement is intended as a sweeping indictment on relying on bare bones deep learning systems and brute force to achieve AGI, it serves as a bit of a litmus test as to where the computer science community is at when it comes to AI .

Currently, were building classical AI systems with the hopes theyll one day be robust enough to mimic the human mind. This is a technology endeavor, meaning computer experts are continuously pushing the limits of what modern hardware and software can do.

The problem with this approach is that its creating a copy of a copy. Quantum physics tells us that, at the very least, our understanding of time is likely different from what might be theultimate universal reality.

How close can robots ever come to imitating humans if they, like us, only think in classical terms? Perhaps a better question is: what happens when AI learns to think in quantum terms while us humans are still stuck with our classical interpretation of reality?

So youre interested in AI? Thenjoin our online event, TNW2020, where youll hear how artificial intelligence is transforming industries and businesses.

Published September 17, 2020 18:52 UTC

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Quantum and classical computers handle time differently. What does that mean for AI? - The Next Web

For the better part of a century, the world's greatest minds have struggled with the mathematical certainty that objects can be in multiple positions at the same time before something causes them to snap into place.

A number of physicists have wondered if good old gravity is responsible for forcing the particle equivalent of a roulette ball to settle into its metaphorical pocket. That's looking a little less likely in the wake of a new experiment.

Researchers from across Europe recently tested a potential explanation of the apparent collapse of a waveform, determined not by observations or weirdly branching multiverses, but by the geometry of spacetime.

It's an idea that has its roots in a paperpublished back in 1966 by the Hungarian physicist Frigyes Karolyhazy, championed decades later by renowned minds like Roger Penrose and Lajos Disi.

In fact, it was Disi who teamed up with a handful of scientists to determine if we could blame gravity for one of quantum physics' most brain-numbing paradoxes.

"For 30 years, I had been always criticised in my country that I speculated on something which was totally untestable," Disi told Science Magazine's George Musser.

New technology has finally made the untestable a possibility. But to understand how it works, we need to take a brief dive into quantum insanity.

Back in the early 20th century, theorists modelled particles as if they were waves in order to reconcile what they were learning about atomics and light.

These particles weren't quite like waves rippling across the surface of a pond, though. Think of the curving line you might draw on a graph to describe your chances of winning a bet in a dice game.

To some physicists, this whole gambling analogy was just a convenient fudge-factor, to be later resolved when we worked out more about the fundamental nature of quantum physics.

Others were adamant quantum physics is as complete as it gets. Meaning it really is a muddy mess of maybes down in the depths of physics.

Explaining how we get from a rolled dice to a clearly defined number describing things like particle spin, position, or momentum is the part that has had everybody stumped.

The famous Swiss physicist Erwin Schrdinger was firmly on team 'fudge factor'.

He came up with that outrageous thought experiment involving a hidden cat that was alive and dead at the same time (until you looked at it), just to show just how nuts the whole 'undecided reality' thing was.

And yet here we are, a century on, and still superposition the idea of objects like electrons(or bigger) occupying multiple states and positions at once until you measure them is a core feature of modern physics.

So much so, we're developing a whole branch of technology quantum computing around the concept.

To avoid needing to invoke half-baked notions of consciousness or infinite co-existing versions of reality to explain why many possibilities become one when we look at a particle, something less whimsical is needed for quantum probability to collapse into.

For physicists like Penrose and Disi, gravity might be that very thing.

Einstein's explanation of this force rests upon a curving fabric of three-dimensional space woven with time's single dimension.Frustratingly, a quantum description of this 'spacetime' continues to elude theorists.

Yet this firm discrepancy between the two fields makes for a good backbone to pull waves of possibility into line.

Penrose's version of this idea rests on the assertion that it takes different amounts of energy for particles to persist in different states.

If we follow Einstein's old E=mc^2 rule, that energy difference manifests as a difference in mass; which, in turn, influences the shape of spacetime in what we observe as gravity.

Given enough of a contrast in all possible states, spacetime's immutable shape will ensure there's a substantial cost to pay, effectively choosing a single low-energy version of a particle's properties to yank into place.

It's an alluring idea, and luckily one with a potentially testable component.For all purposes, that snap should affect a particle's position.

"It is as if you gave a kick to a particle," Frankfurt Institute for Advanced Studies physicist Sandro Donadi told Science Magazine.

Kick an electron enough and you'll force it to cry photons of light. Logically, all that's left is to create a kind of Schrdinger's cat experiment by locking the right kind of material inside a lead box, buried far from the confounding effects of radiation, and listen for its cries. That material, in this case, is germanium.

If Penrose's sums are right, a crystal of germanium should generate tens of thousands of photon flashes over several months as its superpositioned particles settle into measured states.

But Disi and his team didn't observe tens of thousands of photons.

Over a two month period when they conducted the experiment underground five years ago at INFN Gran Sasso National Laboratory, they measured barely several hundred just what you'd expect from the radiation that managed to leak through.

Penrose isn't too worried. If gravity were to cause particles to emit radiation on collapse, it might run against the Universe's tightly controlled laws of thermodynamics, anyway.

Of course, this isn't the end of the story. In future experiments, gravity might yet be shown to be responsible for flattening quantum waves. Right now, anything seems possible.

This research was published in Nature Physics.

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The Fate of Schrdinger's Cat Probably Isn't in The Hands of Gravity, Experiment Finds - ScienceAlert

People thought what we did was totally wacky, recalls Thomas Ebbesen from the University of Strasbourg in France. When we tried to submit [our 2012 Angewandte Chemie] paper,1 there was one referee report that was very short and simply said: This is not science, this is science fiction.

For many, Ebbesens study might indeed sound like make-believe. His team showed it could change the rate and yield of a photoisomerisation reaction by instead of carrying it out in a beaker putting it in a small space between two mirrors. The space contained no chemical catalyst, nothing obvious that might make this possible. What the researchers did is tap into the power of the vacuum field, a weird quantum mechanical soup that surrounds everything.

2012 was an eye-opener for everyone, says Felipe Herrera who leads a molecular quantum technology group at the University of Santiago, Chile. Nobody believed this, and people spent maybe two or three years until they could reproduce the results.

Although vacuum-field catalysis is still in its infancy and doesnt have any practical applications yet, it could bring catalyst-free catalysis, ultra-selective carbon dioxide reduction and new photosensitisers. It might become a powerful tool to steer chemical reactions akin to photocatalysis. I think this field is going to have far-reaching implications, says Herrera.

It is the view of modern physics that there is no such thing as truly empty space, wrote physicist Brian Skinner from Ohio State University, US, on his blog over a decade ago. Physicists discovered that the universe is filled with an energetic soup, boiling and bubbling with particles that appear as fast as they disappear. Although this almost sounds like a ridiculous return to the long-discarded aether theory, experimental results like the Casimir effect have long since established the vacuum fields existence.

But what has been firmly in the realm of physics is now starting to interest chemists, who hope to one day catalyse reactions with this vacuum field. They do this by creating polaritons, hybrid particles that are part light, part matter. They form even in the absence of light when molecules strongly interact with the so-called virtual photons spontaneously thrown up by the vacuum field.

Creating polaritons out of light and matter is not unlike creating a molecule out of two atoms, Herrera explains. Bring two atoms close enough together and they form a molecule, a new entity with new orbitals, and new chemical properties. Similarly, polaritons often have dramatically different reactivities to their parent molecules so dramatic in fact that they could be likened to a new state of matter.

Although a small field, it has seen an uptick in attention from the scientific community. According to Web of Science, the number of studies containing the keyword molecular polariton has doubled, rising from less than 25 in 2017 to more than 50 in 2019. Since the start of the Covid-19 lockdown, around 200 scientists have been attending weekly webinars on polariton chemistry hosted by researchers at the University of California San Diego, US.

I think this field will open many minds, especially among experimental chemistry colleagues, says Herrera. Thats why I like this field so much, because its a bridge between maybe 50 or 60 years of quantum optics and perhaps 100 years of physical chemistry.

Making molecules interact with the vacuum field is as easy as putting them in a cavity. Simply put, optical cavities consist of two mirrors facing each other and separated by only a few nanometres in some cases. Cavities are a major component of lasers where they form a resonator for light waves. But in the dark, they can be used to create polaritons. Free space is infinite and vacuum field fluctuations are very tiny, which is why we dont see strong coupling in free space, Herrera explains. If you confine the field into tiny spaces, then these vacuum fluctuations are very large.

The dream would be to have super selective chemical protocols using cavities

Joel Yuen-Zhou,University of California San Diego

The cavitys size dictates the wavelength of the virtual photons that can live inside it. Matching this wavelength to be resonant with a molecules bond vibration or an electronic transition creates the conditions for lightmatter mixing, forming molecular polaritons.

An experiment to create polaritonic states might seem surprisingly crude: silver-coated glass slides serve as mirrors sandwiching a layer of target molecules. The setup is held together with screws, so the cavitys resonance frequency can be fine-tuned by minutely changing the mirror-to-mirror distance with a screwdriver.

Before 2012, physicists had modified molecules optical properties like light emission rates in this way. But Ebbesens team showed for the first time that sticking molecules inside a cavity can also alter their chemical properties. It was a proof of concept, and other studies conducted since hinted at the tantalising prospect of controlling chemistry in an entirely new way. It was revolutionary, certainly challenging how we think about chemical reactions, says Wei Xiong who works on ultrafast spectroscopy at the University of California San Diego in the US.

Although synthetic chemists might not see cavity catalysts in the catalogues of their favourite chemicals suppliers anytime soon, there has been progress in the field. In a preprint published in 2018, a team around Hidefumi Hiura from Japans NEC Corporation reported a 10,000-fold increase in the rate of ammonia borane hydrolysis when it was put inside a cavity containing water polaritons.2 Last year, the groups of Ebbesen and Strasbourg colleague Joseph Moran showed how coupling to the vacuum field changes the product ratio in a reaction that can produce two different products.3 And earlier this year, scientists led by Kenji Hirai and Hiroshi Ujii from Hokkaido University, Japan, tuned a cavity to the carbonyl stretching motion of ketones and aldehydes, slowing down the rate of a Prins cyclisation by up to 70%.4

People who learn quantum electrodynamics dont often sit in advanced organic chemistry classes and vice versa

Prineha Narang, Harvard University

How far could we push these changes? wonders computational materials scientist Prineha Narang from Harvard University, US. Could we have something that is completely selective to one product and shuts off all the other products, in particular for reactions that are of technological relevance? Carbon dioxide reduction would be one of those reactions, she adds.

While polaritonic chemistry might not become the next big thing for industrial synthesis, flow setups that funnel reagents through a cavity could provide a solution to scaling up reactions. I think it would be very nice to see controlling chemistry of triplet states, suggest Herrera. There are many photosensitisers that are used in industry that rely on electrons becoming unpaired.

The dream would be to have super selective chemical protocols using cavities, says Joel Yuen-Zhou who works on polariton chemistry at the University of California San Diego, US. This is still under development, but it might be the case that with appropriate photonic architectures, this will be possible.

However, so far, researchers havent been able to show that vacuum-field catalysis can do reactions that are impossible or hard to do with other types of chemistry. This is what we would love to demonstrate, says Ebbesen. But for the moment, were trying to understand the underlying mechanism of why some reactions are enhanced and some reactions are slowed down.

For the most part, scientists still dont understand the microscopic mechanism underlying vacuum-field catalysis. When molecules sit inside a cavity, only a small fraction less than 1% are actually occupying polaritonic states. The rest are in dark states, which can be likened to non-bonding orbitals. How exactly macroscopic changes happen with most molecules remaining dark is still a mystery.

Sometimes the evidence is confusing or contradictory, says Herrera. The mechanism that colleagues conclude in one paper doesnt work for a very similar molecule in another paper. Initially, researchers tried to reason that polaritons unpredictable behaviour was due to energetic variations like changes in reaction barrier.

However, first theoretical5 and then experimental6 evidence like the fact that like polar bonds are more strongly influenced than non-polar ones now point to vibrational symmetry as the key to solving the dark state paradox. Vibrational modes can be naturally self-excited or de-excited by the vacuum field depending on their dipolar symmetry, explains Herrera though how this links to reaction rate changes remains unclear.

A model that reproduces let alone predicts how different compounds behave is still missing. What scientists are after is a set of rules not unlike the WoodwardHoffman rules: something simple that nevertheless reflects the complexity of the underlying quantum mechanics.

Most reactions studied so far are slowed down by cavities rather than accelerated not something chemists usually look for in a catalyst. But why this happens and how they can be speeded up remain open questions, says Xiong. Only if we can understand what knobs we need to turn, we can control the selectivity, he adds.

Still, the prospect of doing reactions by simply putting reagents between two mirrors remains intriguing. Whether this is going to be a universal tool or not I think, as of now, I would say no but I wouldnt discard it in the future, says Yuen-Zhou. Just like with photoredox catalysis, you just need to find the right class of reactions.

There might certainly be something said for more people becoming involved and working together within this field. People who learn quantum electrodynamics dont often sit in advanced organic chemistry classes and vice versa theres a gap to be bridged, Narang says. But of course thats also where a lot of exciting discoveries come from.

Read the rest here:

Hybrid lightmatter particles offer tantalising new way to control chemistry - Chemistry World

Of all the reasons for wanting to time-travelsaving someone from a fatal mistake, exploring ancient civilizations, gathering evidence about unsolved crimesrecovering lost information isnt the most exciting. But even if a quest to recover the file that didnt auto-save doesn't sound like a Hollywood movie plot, weve all had moments when weve longed to go back in time for exactly that reason.

Theories of time and time-travel have highlighted an apparent stumbling block: time travel requires changing the past, even simply by adding in the time traveller. The problem, according to chaos theory, is that the smallest of changes can cause radical consequences in the future. In this conception of time travel, it wouldnt be advisable to recover your unsaved document since this act would have huge knock-on effects on everything else.

New research in quantum physics from Los Alamos National Laboratory has shown that the so-called butterfly effect can be overcome in the quantum realm in order to unscramble lost information by essentially reversing time.

In a paper published in July, researchers Bin Yan and Nikolai Sinitsyn write that a thought experiment in unscrambling information with time-reversing operations would be expected to lead to the same butterfly effect as the one in the famous Ray Bradburys story A Sound of Thunder In that short story, a time traveler steps on an insect in the deep past and returns to find the modern world completely altered, giving rise to the idea we refer to as the butterfly effect.

In contrast," they wrote, "our result shows that by the end of a similar protocol the local information is essentially restored.

"The primary focus of this work is not 'time travel'physicists do not have an answer yet to tell whether it is possible and how to do time travel in the real world, Yan clarified.

[But] since our protocol involves a 'forward' and a 'backward' evolution of the qubits, achieved by changing the orders of quantum gates in the circuit, it has a nice interpretation in terms of Ray Bradbury's story for the butterfly effect. So, it is an accurate and useful way to understand our results."

What is the butterfly effect?

The world does not behave in a neat, ordered way. If it did, identical events would always produce the same patterns of knock-on effects, and the future would be entirely predictable, or deterministic. Chaos theory claims that the opposite: total randomness is not our situation either. We exist somewhere in the middle, in a world that often appears random but in fact obeys rules and patterns.

Patterns within chaos are hidden because they are highly sensitive to tiny changes, which means similar but not identical situations can produce wildly different outcomes. Another way of putting it is that in a chaotic world, effects can be totally out of proportion to their causes, like the metaphor of a flap of butterfly wings causing a tornado on the other side of the world. On the tornado side of the world, the storm would seem random, because the connection between the butterfly-flap and the tornado is too complex to be apparent. While this butterfly effect is the classic poetic metaphor illustrating chaos theory, chaotic dynamics also play out in real-world contexts, including population growth in the Canadian lynx species and the rotation of Plutos moons.

Another feature of chaos is that, even though the rules are deterministic, the future is not predictable in the long-term. Since chaos is so sensitive to small variations, there are near-infinite ways the rules could play out and we would need to know an impossible amount of detail about the present and past to map out exactly how the world will evolve.

Similarly, you cant reverse-engineer some piece of information about the past simply by knowing the current and even future situations; time-travel doesnt help retrieve past information, because even moving backwards in time, the chaotic system is still in play and will produce unpredictable effects.

Information scrambling

Unscrambling information which has previously been scrambled is not straightforward in a chaotic system. Yan and Sinitsyns key discovery is that it is nonetheless possible in quantum computing to get enough information via time-reversal which will then enable information unscrambling.

According to Yan, the fact that the butterfly effect does not occur in quantum realms is not a surprising result, but demonstrating information unscrambling is both novel and important.

In quantum information theory, scrambling occurs when the information encoded in each quantum particle is split up and redistributed across multiple quantum particles in the same quantum system. The scrambling is not random, since information redistribution relies on quantum entanglement, which means that the states of some quantum particles are dependent on each other. Although the scrambled result is seemingly chaotic, the information can be put back together, at least in principle, using the entangled relationships.

Importantly, information scrambling is not the same as information loss. To continue the earlier analogy: information loss occurs when a document is permanently deleted from your computer. For information scrambling, imagine cutting and pasting tiny bits of one computer file into every other file on your machine. Each file now contains a mess of information snippets. You could reconstruct the original files, if you remembered exactly which bits were cut and pasted, and did the entire process in reverse.

Physicists are interested in information scrambling for two main reasons. On the theoretical side, its been proposed as a way to explain what happens to information sucked into a black hole. On the more applied side, it could be an important mechanism for quantum computers to store and hide information, and could produce fast and efficient quantum simulators, which are used already to perform complex experiments including new drug discovery.

Yan and Sinitsyn fall into the second camp, and construct what they call a practically accessible scenario to test unscrambling by time-travel. This scenario is still hypothetical, but explores the mathematics of the actual quantum processor used by Google to demonstrate quantum supremacy in 2019.

Yan says: Another potential application is to use this effect to protect information. A random evolution on a quantum circuit can make the qubit robust to perturbations. One may further exploit the discovered effect to design protocols in quantum cryptography.

The set-up

In Yan and Sinitsyn's quantum thought experiment, Alice and Bob are the protagonists. Alice is using a simplified version of Googles quantum processor to hide just one part of the information stored on the computer (called the central qubit) by scrambling this qubits state across all the other qubits (called the qubit bath). Bob is cast as the intruder, much like a malicious computer hacker. He wants the important information originally stored on the central qubit, now distributed across entangled quantum particles in the bath.

Unfortunately, Bobs hack, while successful in getting the information he wanted, leaves a trail of destruction.

If her processor has already scrambled the information, Alice is sure that Bob cannot get anything useful, the authors write. However, Bobs measurement changes the state of the central qubit and also destroys all quantum correlations between this qubit and the rest of the system.

Bob's method of information theft has altered the computer state so that Alice can also no longer access the hidden information. In this case, the damage occurs because quantum states contain all possible values they could have, with assigned probabilities of each value, but these possibilities (represented by the wave function) collapse down to just one value when a measurement is taken. Quantum computing relies on unmeasured quantum systems to store even more information in multiple possible states, and Bobs intrusion has totally altered the computer system.

Reversing time

Theoretically, the behaviour of a quantum system moving backwards in time can be demonstrated mathematically using whats called a time-reversed evolution operator, which is exactly what Alice uses to de-scramble the information.

Her time-reversal is not actually time travel the way we understand it from science fiction, it is literally a reversal of times direction; the system evolves backwards following whatever dynamics are in play, rather than Alice herself revisiting an earlier time. If the butterfly effect held in the quantum world, then this backwards evolution would actually increase the damage Bob had caused, and Alice would only be able to retrieve the hidden information if she knew exactly what that damage was and could correct her calculations accordingly.

Luckily for Alice, quantum systems behave totally differently to non-quantum (classical or semiclassical) chaotic systems. What Yan and Sinitsyn found is that she can apply her time-reversal operation and end up at an "earlier" state which will not be identical with the initial system she set up, but it will also not have increased the damage which occurred later. Alice can then reconstruct her initial system using a method of quantum unscrambling called quantum state tomography.

What this means is that a quantum system can effectively heal and even recover information that was scrambled in the past, without the chaos of the butterfly effect.

Classical chaotic evolution magnifies any state damage exponentially quickly, which is known as the butterfly effect, explain Yan and Sinitsyn. The quantum evolution, however, is

linear. This explains why, in our case, the uncontrolled damage to the state is not magnified by the subsequent complex evolution. Moreover, the fact that Bobs measurement does not damage the useful information follows from the property of entanglement correlations in the scrambled state.

Hypothetical though this scenario may be, the result already has a practical use: verifying whether a quantum system has achieved quantum supremacy. Quantum processors can simulate time-reversal in a way that classical computers cannot, which could provide the next important test for the quantum race between Google and IBM.

So, while time travel is still not in the cards, the quantum world continues to mess with our classical conception of how the world evolves in time, and pushes the limits of computing information.

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Scientists Have Shown There's No 'Butterfly Effect' in the Quantum World - VICE

The expanding Universe, full of galaxies and the complex structure we observe today, arose from a ... [+] smaller, hotter, denser, more uniform state. But even that initial state had its origins, with cosmic inflation as the leading candidate for where that all came from.

Of all the questions humanity has ever pondered, perhaps the most profound is, where did all of this come from? For generations, we told one another tales of our own invention, and chose the narrative that sounded best to us. The idea that we could find the answers by examining the Universe itself was foreign until recently, when scientific measurements began to solve the puzzles that had stymied philosophers, theologians, and thinkers alike.

The 20th century brought us General Relativity, quantum physics, and the Big Bang, all accompanied by spectacular observational and experimental successes. These frameworks enabled us to make theoretical predictions that we then went out and tested, and they passed with flying colors while the alternatives fell away. But at least for the Big Bang it left some unexplained problems that required us to go farther. When we did, we found an uncomfortable conclusion that were still reckoning with today: any information about the beginning of the Universe is no longer contained within our observable cosmos. Heres the disconcerting story.

The stars and galaxies we see today didn't always exist, and the farther back we go, the closer to ... [+] an apparent singularity the Universe gets, as we go to hotter, denser, and more uniform states. However, there is a limit to that extrapolation, as going all the way back to a singularity creates puzzles we cannot answer.

In the 1920s, just under a century ago, our conception of the Universe changed forever as two sets of observations came together in perfect harmony. For the past few years, scientists led by Vesto Slipher had begun to measure spectral lines emission and absorption features of a variety of stars and nebulae. Because atoms are the same everywhere in the Universe, the electrons within them make the same transitions: they have the same absorption and emission spectra. But a few of these nebulae, the spirals and ellipticals in particular, had extremely large redshifts that corresponded to high recession speeds: faster than anything else in our galaxy.

Starting in 1923, Edwin Hubble and Milton Humason began measuring individual stars in these nebulae, determining the distances to them. They were far beyond our own Milky Way: millions of light-years away in most instances. When you combined the distance and redshift measurements together, it all pointed to one inescapable conclusion that was also theoretically supported by Einsteins General theory of Relativity: the Universe was expanding. The farther away a galaxy is, the faster it appears to recede from us.

The original 1929 observations of the Hubble expansion of the Universe, followed by subsequently ... [+] more detailed, but also uncertain, observations. Hubble's graph clearly shows the redshift-distance relation with superior data to his predecessors and competitors; the modern equivalents go much farther. Note that peculiar velocities always remain present, even at large distances, but that the general trend is what's important.

If the Universe is expanding today, that means that all of the following must be true.

Those are some remarkable and mind-bending facts, as they enable us to extrapolate whats going to happen to the Universe as time marches inexorably forwards. But the same laws of physics that tell us whats going to happen in the future can also tell us what happened in the past, and the Universe itself is no exception. If the Universe is expanding, cooling, and getting less dense today, that means it was smaller, hotter, and denser in the distant past.

While matter (both normal and dark) and radiation become less dense as the Universe expands owing to ... [+] its increasing volume, dark energy, and also the field energy during inflation, is a form of energy inherent to space itself. As new space gets created in the expanding Universe, the dark energy density remains constant.

The big idea of the Big Bang was to extrapolate this back as far as possible: to ever hotter, denser, and more uniform states as we go earlier and earlier. This led to a series of remarkable predictions, including that:

All four of these predictions have been observationally confirmed, with that leftover bath of radiation originally known as the primeval fireball and now called the cosmic microwave background discovered in the mid-1960s often referred to as the smoking gun of the Big Bang.

Arno Penzias and Bob Wilson at the location of the antenna in Holmdel, New Jersey, where the cosmic ... [+] microwave background was first identified. Although many sources can produce low-energy radiation backgrounds, the properties of the CMB confirm its cosmic origin.

You might think that this means that we can extrapolate the Big Bang all the way back, arbitrarily far into the past, until all the matter and energy in the Universe is concentrated into a single point. The Universe would reach infinitely high temperatures and densities, creating a physical condition known as a singularity: where the laws of physics as we know them give predictions that no longer make sense and cannot be valid anymore.

At last! After millennia of searching, we had it: an origin for the Universe! The Universe began with a Big Bang some finite time ago, corresponding to the birth of space and time, and that everything weve ever observed has been a product of that aftermath. For the first time, we had a scientific answer that truly indicated not only that the Universe had a beginning, but when that beginning occurred. In the words of Georges Lemaitre, the first person to put together the physics of the expanding Universe, it was a day without yesterday.

A visual history of the expanding Universe includes the hot, dense state known as the Big Bang and ... [+] the growth and formation of structure subsequently. The full suite of data, including the observations of the light elements and the cosmic microwave background, leaves only the Big Bang as a valid explanation for all we see. As the Universe expands, it also cools, enabling ions, neutral atoms, and eventually molecules, gas clouds, stars, and finally galaxies to form.

Only, there were a number of unresolved puzzles that the Big Bang posed, but presented no answers for.

Why did regions that were causally disconnected i.e., had no time to exchange information, even at the speed of light have the same temperatures as one another?

Why were the initial expansion rate of the Universe (which works to expand things) and the total amount of energy in the Universe (which gravitates and fights the expansion) perfectly balanced early on: to more than 50 decimal places?

And why, if we reached these ultra-high temperatures and densities early on, are there no leftover relic remnants from those times in our Universe today?

Throughout the 1970s, the top physicists and astrophysicists in the world worried about these problems, theorizing about possible answers to these puzzles. Then, in late 1979, a young theorist named Alan Guth had a spectacular realization that changed history.

In the top panel, our modern Universe has the same properties (including temperature) everywhere ... [+] because they originated from a region possessing the same properties. In the middle panel, the space that could have had any arbitrary curvature is inflated to the point where we cannot observe any curvature today, solving the flatness problem. And in the bottom panel, pre-existing high-energy relics are inflated away, providing a solution to the high-energy relic problem. This is how inflation solves the three great puzzles that the Big Bang cannot account for on its own.

The new theory was known as cosmic inflation, and postulated that perhaps the idea of the Big Bang was only a good extrapolation back to a certain point in time, where it was preceded (and set up) by this inflationary state. Instead of reaching arbitrary high temperatures, densities, and energies, inflation states that:

until inflation ends. When it ends, the energy that was inherent to space itself the energy thats the same everywhere, except for the quantum fluctuations imprinted atop it gets converted into matter and energy, resulting in a hot Big Bang.

The quantum fluctuations that occur during inflation get stretched across the Universe, and when ... [+] inflation ends, they become density fluctuations. This leads, over time, to the large-scale structure in the Universe today, as well as the fluctuations in temperature observed in the CMB. New predictions like these are essential for demonstrating the validity of a proposed fine-tuning mechanism.

Theoretically, this was a brilliant leap, because it offered a plausible physical explanation for the observed properties the Big Bang alone could not account for. Causally disconnected regions have the same temperature because they all arose from the same inflationary patch of space. The expansion rate and the energy density were perfectly balanced because inflation gave that same expansion rate and energy density to the Universe prior to the Big Bang. And there were no left over, high-energy remnants because the Universe only reached a finite temperature after inflation ended.

In fact, inflation also made a series of novel predictions that differed from that of the non-inflationary Big Bang, meaning we could go out and test this idea. As of today, in 2020, weve collected data that puts four of those predictions to the test:

The large, medium and small-scale fluctuations from the inflationary period of the early Universe ... [+] determine the hot and cold (underdense and overdense) spots in the Big Bang's leftover glow. These fluctuations, which get stretched across the Universe in inflation, should be of a slightly different magnitude on small scales versus large ones.

With data from satellites like COBE, WMAP, and Planck, weve tested all four, and only inflation (and not the non-inflationary hot Big Bang) yields predictions that are in line with what weve observed. But this means that the Big Bang wasnt the very beginning of everything; it was only the beginning of the Universe as were familiar with it. Prior to the hot Big Bang, there was a state known as cosmic inflation, that eventually ended and gave rise to the hot Big Bang, and we can observe the imprints of cosmic inflation on the Universe today.

But only for the last tiny, minuscule fraction of a second of inflation. Only, perhaps, for the final ~10-33 seconds of it (or so) can we observe the imprints that inflation left on our Universe. Its possible that inflation lasted for only that duration, or for far longer. Its possible that the inflationary state was eternal, or that it was transient, arising from something else. Its possible that the Universe did begin with a singularity, or arose as part of a cycle, or has always existed. But that information doesnt exist in our Universe. Inflation by its very nature erases whatever existed in the pre-inflationary Universe.

The quantum fluctuations that occur during inflation do indeed get stretched across the Universe, ... [+] but they also cause fluctuations in the total energy density. These field fluctuations cause density imperfections in the early Universe, which then lead to the temperature fluctuations we experience in the cosmic microwave background. The fluctuations, according to inflation, must be adiabatic in nature.

In many ways, inflation is like pressing the cosmic reset button. Whatever existed prior to the inflationary state, if anything, gets expanded away so rapidly and thoroughly that all were left with is empty, uniform space with the quantum fluctuations that inflation creates superimposed atop it. When inflation ends, only a tiny volume of that space somewhere between the size of a soccer ball and a city block will become our observable Universe. Everything else, including any of the information that would enable us to reconstruct what happened earlier in our Universes past, now lies forever beyond our reach.

Its one of the most remarkable achievements of science of all: that we can go back billions of years in time and understand when and how our Universe, as we know it, came to be this way. But like many adventures, revealing those answers has only raised more questions. The puzzles that have arisen this time, however, may truly never be solved. If that information is no longer present in our Universe, it will take a revolution to solve the greatest puzzle of all: where did all this come from?

Read more:

How Physics Erases The Beginning Of The Universe - Forbes