Category Archives: Quantum Physics

Im not saying its all true, says Christoph Simon, a physicist at the University of Calgary in Canada. Im just saying it is not crazy to look for it. He is talking about the possibility that life has found ways to make use of quantum effects in a host of essential phenomena, from photosynthesis and the navigational abilities of birds to consciousness.

The idea has long been seen as a bit fringe, on the assumption that such fragile effects must quickly disappear in the warm, wet environment of cells. Quantumness tends to prosper in very cold systems that are carefully isolated rather than part of a tepid soup awash with other activity.

But that is beginning to change, with tentative evidence for quantum behaviours in the machinery of cells and hints that quantum biology may not play by the conventional rules governing the subatomic world, raising new questions about the boundary between the classical and quantum realms.

You could say, well, all molecules are quantum mechanical, so everything in biology is quantum mechanical, says Greg Scholes, a chemist at Princeton University. But the idea of quantum biology only really gets interesting, he says, with the possibility that it explains emergent macroscopic behaviour that cant be predicted using classical laws.

Finding such behaviour typically means searching for evidence of archetypal quantum traits such as superposition, in which a system appears to exist in multiple states simultaneously before it loses this so-called quantum coherence and collapses into one state or another a process called decoherence.

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Quantum biology: New clues on how life might make use of weird physics - New Scientist

CAMBRIDGE, Mass. Could moving atoms closer together than ever before open the door to the next quantum breakthrough? Physicists at the Massachusetts Institute of Technology have developed a new technique that allows them to arrange atoms in two distinct layers separated by a mere 50 nanometers about 2,000 times thinner than a human hair. This monumental achievement opens up exciting possibilities for studying exotic quantum phenomena and developing novel technologies.

The study, published in Science andled by Professor Wolfgang Ketterle, used laser light to trap and cool dysprosium atoms to ultra-low temperatures near absolute zero. At these extreme conditions, the atoms behave more like waves than particles, enabling researchers to manipulate them with exquisite precision.

Imagine a pair of invisible sheets, each made up of a single layer of atoms. Now, picture bringing those sheets so close together that theyre almost touching, but not quite. Thats essentially what the MIT scientists have accomplished, except on a scale so tiny its difficult to wrap your head around.

To put it in perspective, if an atom were the size of a marble, the two layers would be separated by just a few inches. But because atoms are so incredibly small, the actual distance between the layers is only 50 nanometers. Thats like taking two pieces of paper and holding them apart with a single strand of spider silk.

We have gone from positioning atoms from 500 nanometers to 50 nanometers apart, and there is a lot you can do with this, says Wolfgang Ketterle, the John D. MacArthur Professor of Physics at MIT, in a media release. At 50 nanometers, the behavior of atoms is so much different that were really entering a new regime here.

Creating these atomic bilayers required a clever trick. The researchers used two different colors of laser light, each one specifically tuned to interact with atoms in a particular quantum state, or energy level. Its a bit like having two TV remote controls, one for each layer of atoms. By carefully adjusting the laser beams, they were able to trap the atoms and move them around with nanometer precision.

What makes this setup truly special is the way the atoms in the two layers interact with each other. Even though theyre not physically touching, the atoms can still feel each others presence through a peculiar force called dipolar interaction. Its similar to how two tiny bar magnets would attract or repel each other, even from a short distance.

In the atomic realm, these dipolar interactions can give rise to all sorts of strange and wonderful behaviors. For example, the researchers observed that the atoms in one layer could actually talk to the atoms in the other layer and exchange energy, almost like they were engaged in a microscopic game of telephone. This phenomenon, known as sympathetic cooling, could potentially be used to build ultra-efficient refrigerators for cooling down quantum computers.

But the most exciting possibilities lie in the realm of fundamental physics. By studying how atoms behave in these closely spaced bilayers, scientists hope to gain new insights into exotic states of matter like superfluids and quantum magnets. These materials have properties that seemingly defy the laws of classical physics, such as the ability to flow without friction or resist changes in magnetic fields.

Down the road, the atomic bilayer setup could also be used as a platform for developing quantum technologies, such as ultra-precise sensors, secure communication networks, and powerful computers that can solve problems beyond the reach of any classical machine. Its a bit like having a miniature quantum playground where scientists can tinker with the building blocks of matter and see what new gadgets they can dream up.

Of course, theres still a lot of work to be done before these applications become a reality. The MIT team plans to conduct more experiments to better understand the subtle dance of dipolar interactions between the atomic layers. They also want to explore what happens when the atoms are cooled down even further to temperatures so low that quantum effects completely take over.

But even at this early stage, the results are nothing short of remarkable. By pushing the boundaries of atomic manipulation, these researchers have given us a glimpse into a world thats both strangely familiar and utterly alien a world where the rules of quantum mechanics reign supreme, and the line between science and science fiction starts to blur.

As we continue to explore this strange and wonderful frontier, one thing is clear: the future of physics is looking brighter than ever, and it all starts with a humble pair of atomic sheets, separated by a distance so small its almost hard to believe. But in the grand scheme of things, that tiny gap might just be the key to bridging the gap between the world we know and the one weve only begun to imagine.

StudyFinds Editor-in-ChiefSteve Fink contributedto this report.

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Scientists move atoms so close together it may change quantum physics forever - - Study Finds

Pan, a professor of modern physics and executive vice-president at the University of Science and Technology of China (USTC), has done pioneering work in multi-article interferometry and quantum experiments in space, the societys Fellows Directory says.

It also praises his team for having closed major loopholes for secure quantum communication associated with imperfect devices, making it a viable technology under realistic conditions.

Pan also featured on the 2017 Natures 10, the premier magazines annual list of the people who matter most in science. He had lit a fire under Chinas quantum technology efforts since returning full-time in 2008 after training in Europe, Nature said, labelling Pan as a physicist who took quantum communication to space and back.

In 2016, under Pans leadership, China launched the worlds first quantum science space satellite, Micius, with a mission to establish a secure communication line between China and Europe, a fact mentioned also in the Royal Society directory.

The Royal Society bio also lauded Pan for his achievements in quantum computing technology. His team demonstrated quantum computational advantage, validating the feasibility of quantum computing systems to outperform classical machines in solving specific problems, his bio says.

The breakthroughs made by Pans USTC team are often reported by top academic journals.

Pan is also an academician of the Chinese Academy of Sciences (CAS), Chinas premier research institute, and is director of the CAS Centre for Excellence in Quantum Information and Quantum Physics in Anhui province, where he is based with the USTC.

The USTC is not only home to leading quantum physicists such as Pan, but also an innovation hub that has spawned many start-ups, thanks to steady scientific breakthroughs, a competitive talent pool and generous local government support.

The Royal Society, formally the Royal Society of London for Improving Natural Knowledge, was founded in 1660 and is the worlds oldest continuous scientific academy.

In 2022, George Gao Fu, then head of the Chinese Centre for Disease Control and Prevention, a leading scientist in the field of virology and immunology, was elected by the society for his contribution to the fight against the Covid-19 pandemic.

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Chinas father of quantum named Royal Society fellow as US targets sector - South China Morning Post

In the realm of quantum physics, proximity plays a crucial role. As atoms interact more strongly when they are positioned closely together, scientists have long sought ways to arrange them as tightly as possible in quantum simulators.

These simulators allow researchers to explore exotic states of matter and build novel quantum materials. However, there has been a limit to how close atoms could be positioneduntil now.

Typically, scientists cool the atoms to a stand-still and use laser light to arrange them, but the wavelength of light has restricted the minimum distance between particles to around 500 nanometers.

Now, a team of physicists at MIT has developed a breakthrough technique that enables them to position atoms a mere 50 nanometers apart. To put this into perspective, a red blood cell measures about 1,000 nanometers in width.

The MIT team, led by Wolfgang Ketterle, the John D. MacArthur Professor of Physics, demonstrated their new approach using dysprosium, the most magnetic atom in nature.

By manipulating two layers of dysprosium atoms and precisely positioning them 50 nanometers apart, they observed magnetic interactions 1,000 times stronger than if the layers were separated by the previous limit of 500 nanometers.

We have gone from positioning atoms from 500 nanometers to 50 nanometers apart, and there is a lot you can do with this, says Ketterle. At 50 nanometers, the behavior of atoms is so much different that were really entering a new regime here.

Furthermore, the researchers were able to measure two new effects caused by the atoms proximity: thermalization, where heat transfers from one layer to another, and synchronized oscillations between the layers. These effects diminished as the layers were spaced farther apart.

Conventional techniques for manipulating and arranging atoms have been limited by the wavelength of light, which typically stops at 500 nanometers. This optical resolution limit has prevented scientists from exploring phenomena that occur at much shorter distances.

Conventional techniques stop at 500 nanometers, limited not by the atoms but by the wavelength of light, explains Ketterle. We have found now a new trick with light where we can break through that limit.

The teams innovative approach begins by cooling a cloud of atoms to about 1 microkelvin, just above absolute zero, causing the atoms to come to a near-standstill.

They then use two laser beams with different frequencies and circular polarizations to create two groups of atoms with opposite spins.

Each laser beam forms a standing wave, a periodic pattern of electric field intensity with a spatial period of 500 nanometers.

By tuning the lasers such that the distance between their respective peaks is as small as 50 nanometers, the atoms gravitating to each lasers peaks are separated by the same distance.

To achieve this level of precision, the lasers must be extremely stable and resistant to external noise. The team realized they could stabilize both lasers by directing them through an optical fiber, which locks the light beams in place relative to each other.

The idea of sending both beams through the optical fiber meant the whole machine could shake violently, but the two laser beams stayed absolutely stable with respect to each others, says lead author and physics graduate student Li Du.

By applying their technique to dysprosium atoms, the researchers observed two novel quantum phenomena at the extremely close proximity of 50 nanometers.

First is collective oscillation, where vibrations in one layer caused the other layer to vibrate in sync. Next is thermalization, where one layer transferred heat to the other purely through magnetic fluctuations in the atoms.

Until now, heat between atoms could only by exchanged when they were in the same physical space and could collide, notes Du. Now we have seen atomic layers, separated by vacuum, and they exchange heat via fluctuating magnetic fields.

The teams results introduce a new technique that can be applied to many other atoms to study quantum phenomena.

They believe their approach can be used to manipulate and position atoms into configurations that could generate the first purely magnetic quantum gate.

This would be a key building block for a new type of quantum computer.

We are really bringing super-resolution methods to the field, and it will become a general tool for doing quantum simulations, says Ketterle. There are many variants possible, which we are working on.

In summary, the MIT teams pioneering technique opens up a new frontier in quantum physics, enabling scientists to explore previously inaccessible phenomena and build novel quantum materials.

By positioning atoms a mere 50 nanometers apart, they have unlocked a realm where magnetic interactions reign supreme and quantum effects emerge in stunning clarity.

As researchers continue to refine and expand upon this approach, they inch closer to the development of purely magnetic quantum gates and the realization of cutting-edge quantum computers.

The future of quantum simulations looks brighter than ever, and the possibilities are limited only by the imagination of the scientists who dare to push the boundaries of what is possible.

The studys co-authors include Pierre Barral, Michael Cantara, Julius de Hond, and Yu-Kun Lu, all members of the MIT-Harvard Center for Ultracold Atoms, the Department of Physics, and the Research Laboratory of Electronics at MIT.

The full study was published in the journal Science.

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"Impossible" quantum effects seen when squishing atoms together - Earth.com

Tauonium: The Smallest and Heaviest Atom with Pure Electromagnetic Interaction. Credit: Science China Press

Recent discoveries in quantum physics have revealed simpler atomic structures than hydrogen, involving pure electromagnetic interactions between particles like electrons and their antiparticles. This advancement has significant implications for our understanding of quantum mechanics and fundamental physics, highlighted by new methods for detecting tauonium, which could revolutionize measurements of particle physics.

The hydrogen atom was once considered the simplest atom in nature, composed of a structureless electron and a structured proton. However, as research progressed, scientists discovered a simpler type of atom, consisting of structureless electrons (e-), muons (-), or tauons (-) and their equally structureless antiparticles. These atoms are bound together solely by electromagnetic interactions, with simpler structures than hydrogen atoms, providing a new perspective on scientific problems such as quantum mechanics, fundamental symmetry, and gravity.

To date, only two types of atoms with pure electromagnetic interactions have been discovered: the electron-positron bound state discovered in 1951 (Phys Rev 1951;82:455) and the electron-antimuon bound state discovered in 1960 (Phys Rev Lett 1960;5:63). Over the past 64 years, there have been no other signs of such atoms with pure electromagnetic interactions, although there are some proposals to search for them in cosmic rays or high-energy colliders.

Tauonium, composed of a tauon and its antiparticle, has a Bohr radius of only 30.4 femtometers (1 femtometer = 10-15 meters), approximately 1/1741 (0.057%) of the Bohr radius of a hydrogen atom. This implies that tauonium can test the fundamental principles of quantum mechanics and quantum electrodynamics at smaller scales, providing a powerful tool for exploring the mysteries of the micro material world.

Recently, a study titled Novel method for identifying the heaviest QED atom was published in the comprehensive journal Science Bulletin, proposing a new approach used to discover tauonium. The study demonstrates that by collecting data of 1.5 ab-1 near the threshold of tauon pair production at an electron and positron collider, and selecting signal events containing charged particles accompanied by the undetected neutrinos carrying away energy, the significance of observing tauonium will exceed 5. This indicates a strong experimental evidence for the existence of tauonium.

The study also found that using the same data, the precision of measuring the tau lepton mass can be improved to an unprecedented level of 1 keV, two orders of magnitude higher than the highest precision achieved by current experiments. This achievement will not only contribute to the precise testing of the electroweak theory in the Standard Model but also have profound implications for fundamental physics questions such as lepton flavor universality.

This achievement serves as one of the most important physical objectives of the proposed Super Tau-Charm Facility (STCF) in China or the Super Charm-Tau Factory (SCTF) in Russia: to discover the smallest and heaviest atom with pure electromagnetic interactions by running the machine near the tauon pair threshold for one year and to measure the tau lepton mass with a high precision. These discoveries will provide deeper insights and understanding into humanitys exploration of the microscopic world.

Reference: Novel method for identifying the heaviest QED atom by Jing-Hang Fu, Sen Jia, Xing-Yu Zhou, Yu-Jie Zhang, Cheng-Ping Shen and Chang-Zheng Yuan, 4 April 2024, Science Bulletin. DOI: 10.1016/j.scib.2024.04.003

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Beyond Hydrogen: Discovery of Tiny New Atom Tauonium With Massive Implications - SciTechDaily

Harvard scientists have demonstrated that quantum coherence can persist through chemical reactions in ultracold molecules, suggesting broader applications for quantum information science and potentially in more common environmental conditions.

If you zoom in on a chemical reaction to the quantum level, youll notice that particles behave like waves that can ripple and collide. Scientists have long sought to understand quantum coherence, the ability of particles to maintain phase relationships and exist in multiple states simultaneously; this is akin to all parts of a wave being synchronized. It has been an open question whether quantum coherence can persist through a chemical reaction where bonds dynamically break and form.

Now, for the first time, a team of Harvard scientists has demonstrated the survival of quantum coherence in a chemical reaction involving ultracold molecules. These findings highlight the potential of harnessing chemical reactions for future applications in quantum information science.

I am extremely proud of our work investigating a very fundamental property of a chemical reaction where we really didnt know what the result would be, said senior co-author Kang-Kuen Ni, Theodore William Richards Professor of Chemistry and Professor of Physics. It was really gratifying to do an experiment to find out what Mother Nature tells us.

In the paper, published in Science, the researchers detailed how they studied a specific atom-exchange chemical reaction in an ultra-cold environment involving 40K87Rb bialkali molecules, where two potassium-rubidium (KRb) molecules react to form potassium (K2) and rubidium (Rb2) products. The team prepared the initial nuclear spins in KRb molecules in an entangled state by manipulating magnetic fields and then examined the outcome with specialized tools. In the ultra-cold environment, the Ni Lab was able to track the nuclear spin degrees of freedom and to observe the intricate quantum dynamics underlying the reaction process and outcome.

The work was undertaken by several members of Nis Lab, including Yi-Xiang Liu, Lingbang Zhu, Jeshurun Luke, J.J. Arfor Houwman, Mark C. Babin, and Ming-Guang Hu.

Utilizing laser cooling and magnetic trapping, the team was able to cool their molecules to just a fraction of a degree above Absolute Zero. In this ultracold environment, of just 500 nanoKelvin, molecules slow down, enabling scientists to isolate, manipulate, and detect individual quantum states with remarkable precision. This control facilitates the observation of quantum effects such as superposition, entanglement, and coherence, which play fundamental roles in the behavior of molecules and chemical reactions.

By employing sophisticated techniques, including coincidence detection where the researchers can pick out the exact pairs of reaction products from individual reaction events, the researchers were able to map and describe the reaction products with precision. Previously, they observed the partitioning of energy between the rotational and translational motion of the product molecules to be chaotic [Nature 593, 379-384 (2021)]. Therefore, it is surprising to find quantum order in the form of coherence in the same underlying reaction dynamics, this time in the nuclear spin degree of freedom.

The results revealed that quantum coherence was preserved within the nuclear spin degree of freedom throughout the reaction. The survival of coherence implied that the product molecules, K2 and Rb2, were in an entangled state, inheriting the entanglement from the reactants. Furthermore, by deliberately inducing decoherence in the reactants, the researchers demonstrated control over the reaction product distribution.

Going forward, Ni hopes to rigorously prove that the product molecules were entangled, and she is optimistic that quantum coherence can persist in non-ultracold environments.

We believe the result is general and not necessarily limited to low temperatures and could happen in more warm and wet conditions, Ni said. That means there is a mechanism for chemical reactions that we just didnt know about before.

First co-author and graduate student Lingbang Zhu sees the experiment as an opportunity to expand peoples understanding about chemical reactions in general.

We are probing phenomena that are possibly occurring in nature, Zhu said. We can try to broaden our concept to other chemical reactions. Although the electronic structure of KRb might be different, the idea of interference in reactions could be generalized to other chemical systems as well.

Reference: Quantum interference in atom-exchange reactions by Yi-Xiang Liu, Lingbang Zhu, Jeshurun Luke, J. J. Arfor Houwman, Mark C. Babin, Ming-Guang Hu and Kang-Kuen Ni, 16 May 2024, Science. DOI: 10.1126/science.adl6570

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Quantum Coherence: Harvard Scientists Uncover Hidden Order in Chemical Chaos - SciTechDaily

Netflixs 3 Body Problem premiered March 21, and theres a lot of science! The new Netflix series from screenwriter Alexander Woo and Game of Thrones shepherds David Benioff and D.B. Weiss adapts a bestselling sci-fi trilogy by Chinese writer Liu Cixin, an engineer with a high-level understanding of physics. The story that unfolds over 3 Body and its two sequels, also known as the Remembrance of Earths Past series, won acclaim for its vision of a future based on a variety of ideas about quantum mechanics and how they might impact a future interstellar existential crisis. In 3 Bodys fictional universe, far-flung theory plays out in real time in the lives of a far-away alien species and its attempts to both interact with and influence humans here on Earth.

Fortunately for audiences who arent Einsteins, the Netflix series shifts much of the drama away from the skies and onto humans it even creates a bunch of entirely new characters to give us people to care about in between all the physics. Lius series includes two more books following the first novel; the Netflix series follows the first book, then spins off in its own direction for a while before setting us up for book two. What they both have in common is a zoomed-out view of quantum mechanics and astrophysics underlying all the cool space stuff. Our heroes and villains are all scientists whose decisions and conflicts dictate humanitys course both now and in the distant future. With the assistance of an actual astrophysicist, lets go through the basics you need to know to understand what the heck is happening in this show.

The three-body problem has existed ever since humans began to understand gravity and how it works. You probably know that the Earth rotates around the sun because the suns gravitational field is exerting a pull over our planet and all the others in our solar system. Were able to interact with the sun in that way because as planets, our individual gravitational spheres are all less powerful than the sun, and none are powerful enough to exert a hold on each other. Its the same with our moon its caught in Earths gravitational field, so it floats along hanging out with us.

In other words, two objects whose gravitational fields interact will always form stable orbits along a predictable, unchanging path. Newton figured this out, along with the formula for predicting their orbits, in 1687. Its sometimes called the two-body problem. If you were to introduce another star into the mix, youd probably wind up with a binary star system where both stars form stable orbits around a gravitational center. The most common sort of star is one with a stable binary partner, which makes our sun, a solo star, fairly rare. Binary star systems can have stable planets, too, and these types of systems can often be mapped and plotted and predicted by astronomers and physicists.

But that only works with two objects with gravitational forces. When you add a third object into the mix, all bets are off. Instead of stabilizing, the third element creates chaos and causes the objects to fly around and interact in completely unpredictable ways spinning off into space, crashing into each other, or bouncing off one anothers gravitational spheres and careening in completely different directions.

To explain why this happens, I turned to astrophysicist Dr. Charles J. Horowitz, who told me that the key here is the law of conservation of energy thats the one that tells us that energy in a closed system can never be created or destroyed. Conservation of energy implies that a planet will orbit a single star forever and can never escape to infinity, Horowitz wrote in an email. In other words, once a planet becomes trapped inside of a stars gravitational field, it cant create the additional energy it would need to propel itself out of it.

Two stars, on the other hand, can exchange energy and possibly eject an orbiting planet, Horowitz said.

This, then, is the three-body problem: How do we stabilize three gravitational objects or predict what their orbits might be?

For centuries, scientists were unable to find any starting point from which the three objects could form stable orbits in relationship to one another. In recent decades, scientists have come closer; increasingly, using computational algorithms and, in at least one instance, modeling their predictions on intoxicated humans, weve found multiple solutions to create stability among our three hypothetical objects. But the majority of these solutions are difficult if not impossible to model in reality, so its not clear how well they work out of the realm of theory.

The central conceit of 3 Body Problem is exactly this scenario an alien species on a distant planet has evolved the capacity to become a technologically advanced civilization but its planet exists within a solar system with three different suns.

Because of the three-body problem, these suns are constantly exerting gravitational chaos over one another, flinging each other to and fro across the cosmos and in the process wreaking climate havoc on the planet caught in the middle. The alien race, called the Trisolarans, has thus had its civilizations wiped out and destroyed, over and over, for millennia.

I asked Horowitz how likely this scenario would be, and he essentially backed up Three Bodys author, Liu Cixin. In the short term it might be fine, Horowitz said. Over very long times (say, billions of years) many orbits of planets around two stars are thought to be unstable.

If life takes billions of years to evolve (as it did on Earth) then such a planet may not provide a suitable environment. However, there may be certain configurations of the three bodies that are stable for long times and could be suitable for life. Or life could develop or colonize the world more quickly, he added.

This is precisely the situation the Trisolarans face: From time to time, their three bodies stabilize for long periods, giving their civilizations enough time to rapidly advance and flourish. Inevitably, though, the stable eras give way to chaotic eras, when their suns resume their volatility.

The existential problem of the Trisolarans which a select group of Earthlings eventually devote themselves to solving as well is how to know and prepare for a chaotic era when you cant predict one. In essence, theyre living out the three-body problem in real time.

This scenario might sound improbable, but its actually not and its a crucial part of the plot of 3 Body Problem. In the show, we learn that the Trisolarans are able to essentially spy on Earth through the use of a proton thats been transmitted to Earth to act as a simultaneous receiver and transmitter for its twin proton, which remains on Trisolaris.

This is possible through a mind-bending phenomenon known as quantum entanglement. Scientists have observed this property in subatomic particles which essentially operate as one entity, even when theyre separated by billions of light years. In fact, notes Dr. Horowitz, [Its] perhaps better to say the two entangled particles share the information rather than receive and transmit it. In other words, they arent so much communicating with one another as simultaneously receiving information from both locations even though theyre on completely different planets.

This may sound like the most unbelievable part of the 3 Body series even in the show, when our plucky cosmologist, Jin Cheng, presents the idea to her colleagues, they laugh at her and dismiss the idea as a silly game rather than real science.

In fact, Chengs idea is based on a real phenomenon known as nuclear thermal propulsion, sometimes called nuclear pulse propulsion. As it turns out, nuclear propulsion produces very little radiation if the engines using it are activated in space instead of on Earth and the benefits include reduced energy use, reduced exposure to cosmic radiation, and speedier rockets. The Department of Energy even has a web page devoted to touting the benefits of nuclear propulsion.

Although the series presents Chengs domino effect idea as far-fetched, the US has a history of experimenting with nuclear thermal propulsion. As Horowitz explained, Project Orion, early in the Cold War, tried to develop a rocket powered by small atomic bombs.

However, if youre wondering about all that radiation, youre not alone. The first version of Project Orion was ultimately canceled because mid-century scientists were unable to solve the big problem: the near-certainty of deadly nuclear fallout that would result from any attempt to launch a nuclear-powered rocket into space from Earth.

A shame, really. It would have been a very good rocket, Horowitz said. Modern iterations of Orion have focused on launching similar rockets from within space and limiting astronauts exposure to radiation.

Perhaps the most difficult aspect of 3 Body to conceptualize involves exactly what the Trisolarans do to the aforementioned proton before they shoot it off into space: They unfold its multiple dimensions into a massive, planet-sized amount of space, inscribe a giant super-computer onto its planes, and then re-fold it back into its original microscopic size.

This is a difficult feat to imagine, much less conceive in reality. Yet this practice exists, at least in theory, as an idea of multidimensional unfolding. Imagine this the way you might imagine creating a simple paper fortune-teller. The paper shape starts out almost fully flat, on a single plane but it can be uncompressed to reveal more and more layers, until you have a neat schoolyard divination tool.

Now imagine this happening on a grand scale, and with even more dimensions than the three we experience here on Earth. There are multiple processes for how to do it, and multiple ways to try to illustrate what examples might look like in reality. The most famous example is an object that mathematicians and physicists call a hypercube or a tesseract (no, not that one) a cube equivalent that exists in at least four dimensions. Heres one attempt to imagine what one might look like:

Humans have devoted considerable time to trying to capture the essence of this; one famous early work of science fiction, Flatland, was published in 1884 by Edwin Abbott Abbot as a satirical attempt to introduce Victorians to the whole idea of higher dimensions by positing the existence of a society of people who existed in two planes only. Today, we can find equivalent thought experiments in places like YouTube:

Of course, none of this fully explains whether it would be possible to unfold a proton into the size of a planet and then inscribe a super-computer onto it. When I asked Horowitz about this, he replied with ??

And honestly, that might be a fair way to respond to many of the scientific ideas we find in Lius expansive series. Ultimately, its built less on whats real, and what we definitely know, than whats possible given the incredible advances weve made in theoretical physics emphasis on theory.

In other words, 3 Body collides science and fiction like two protons. The result is a wild, unique ride thats worth suspending a little disbelief.

No. Do not try this trick at home. Thankfully, some parts of 3 Body remain purely in the realm of the fantastic.

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Netflixs 3 Body Problem: The science explained by an astrophysicist - Vox.com

Article Highlight | 22-Mar-2024

Quantum entanglement changes in atomic nuclei in ways that differ from other systems

DOE/US Department of Energy

image:

Left: partitions where the set of blue points occupy one region and the set of black points another region, similar to how many systems work. Right: the partitions that occur in nuclei, where the partitions of blue and black points occupy the same regions

Credit: Image courtesy of Thomas Papenbrock.

Entanglement is what Einstein called spooky action at a distance. It is a key part of what distinguishesquantum mechanicsfrom our everyday experience. In quantum mechanics, scientists use a measurement called entanglement entropy to quantify the amount of the entanglement between two subsystemsfor example, between a system being studied and its environment. Large entanglement entropies indicate that a system has strong correlations to its environment. In many systems, the entanglement entropies are proportional to the area that separates a system from its environment. This is also true for black holes, where the energy-related entropy growth is proportional to the area of the event horizon. But thenucleiof atoms are different. The complicated interactions innucleilead to entanglement entropies that grow like the volume of the system of interest, not like its surface area.

Computing the state of a quantum system is hard because doing so requires scientists to accurately capture the systems entanglement with its environment. New research quantifies entanglement entropies forneutronmatter. Using related measures, the research also quantifies this entropy for atomicnuclei. This work can contribute toquantum computingby helping researchers understand how the number of operations necessary to prepare a state on a quantum chip grows with increasing entanglement entropy.

The researchers studied entanglement entropies between the mean-field space and its environment in nuclear systems. As entanglement entropies are hard to compute, the researchers also derived relations to easier-to-compute measures. The research showed that entanglement entropies are related to other quantities that are easier to compute and that can serve as entanglement witnesses. General arguments also suggest that the entanglement entropy in nuclear systems fulfills a volume law instead of an area law. This work tested and confirmed these results by computing entanglement entropies of models for atomicnucleiand neutron matter.

This material is based on work supported by the Department of Energy (DOE) Office of Science, Office of Nuclear Physics and by the Quantum Science Center, a DOE National Quantum Information Science Research Center. Computer time was provided by the Innovative and Novel Computational Impact on Theory and Experiment (INCITE) program. This research used resources from the Oak Ridge Leadership Computing Facility at Oak Ridge National Laboratory.

Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.

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Entanglement entropies of nuclear systems gro - EurekAlert

By University of Virginia College and Graduate School of Arts & Sciences March 23, 2024

The quest for a theory of everything, tracing back to before Archimedes and significantly advanced in the last century through Albert Einsteins theory of general relativity and quantum mechanics, has encountered a major challenge due to their conflicting explanations of gravity. Kent Yagis innovative research at the University of Virginia, utilizing artificial intelligence and backed by a prestigious CAREER grant from the National Science Foundation, aims to bridge this gap, offering new insights into gravity and the universes fundamental forces, while also enhancing STEM education through community and educational outreach. (Artists concept). Credit: SciTechDaily.com

Long before Archimedes suggested that all phenomena observable to us might be understandable through fundamental principles, humans have imagined the possibility of a theory of everything. Over the past century, physicists have edged nearer to unraveling this mystery. Albert Einsteins theory of general relativity provides a solid basis for comprehending the cosmos at a large scale, while quantum mechanics allows us to grasp its workings at the subatomic level. The trouble is that the two systems dont agree on how gravity works.

Today, artificial intelligence offers new hope for scientists addressing the massive computational challenges involved in unraveling the mysteries of something as complex as the universe and everything in it, and Kent Yagi, an associate professor with the University of Virginias College and Graduate School of Arts & Sciences is leading a research partnership between theoretical physicists and computational physicists at UVA that could offer new insight into the possibility of a theory of everything or, at least, a better understanding of gravity, one of the universes fundamental forces. The work has earned him a CAREER grant from the National Science Foundation, one of the most prestigious awards available to the nations most promising young researchers and educators.

One aspect of Einsteins theory of general relativity is that objects moving through space generate waves, much like a boat moving through the water, but even when those waves are created by planets, stars and galaxies, or even black holes that can create the strongest gravitational fields possible, they are still incredibly small. Consequently, it was almost a hundred years after Einstein first published his ideas on gravitational waves that the technological means to observe them were developed. In 2015, a program known as LIGO, or the Laser Interferometer Gravitational Wave Observatory, one of the largest projects ever funded by the NSF, detected gravitational waves for the first time, which led to a Nobel Prize in Physics for the projects leaders.

Physicist Kent Yagi, an associate professor with the University of Virginias College and Graduate School of Arts & Sciences has won a CAREER grant from the National Science Foundation, one of the most prestigious awards available to the nations most promising young researchers and educators. University of Virginia College and Graduate School of Arts & Sciences

The discovery was one of the most important moments in physics in the last hundred years, Yagi said.

And as the technology needed to observe subatomic phenomena advances, the computing capacity necessary to process massive amounts of data astronomers are collecting about the universe has also advanced. Additionally, new developments in machine learning and artificial intelligence in recent years are allowing scientists to create and test complex mathematical models describing the phenomenon they observe at a pace that was once unimaginable.

Yagi studies the massive gravitational waves generated by pairs of black holes and binary neutron stars some of the densest objects in the universe that are as much as 1013 times more powerful than a typical fridge magnet, according to Yagi and he uses those phenomena to test Einsteins theories about gravity and to probe the fundamental laws of nuclear physics looking for information that will help resolve the disconnect between Einsteins theory and quantum mechanics.

The CAREER grant, which will bring $400,000 in funding to the College over the next five years, will create opportunities for current and future graduate students interested in developing and applying machine learning algorithms that will help explain and predict gravitational wave observations and give us a deeper understanding of gravitys behavior.

Once the computational algorithms are fine-tuned a process that should take as little as a few weeks Yagi said his team will be able to process the data collected by LIGO to test Einsteins theory a hundred times faster.

And the amount of space we can search for that data will increase by a factor of ten, Yagi said.

One of the requirements of the CAREER award is that recipients also build educational and community outreach projects into their work, and some of the funding will create jobs for undergraduates who will work with Yagi to develop educational software for high school students interested in physics, which, Yagi hopes, will inspire the next generation of Nobel-prize winning scientists.

How much closer will this bring us to a theory of everything?

There are still a lot of problems to be solved, Yagi said. Im hoping Ill see it in my lifetime, but I dont want to be too optimistic.

Proving a theory is almost impossible, Yagi explained. Theres always going to be measurement error in any experiment, but were going to keep trying to see if we find some evidence to disprove general relativity. At the same time, we just keep discovering how beautiful and correct it appears to be.

Yagis work and the attention its receiving drew praise from his colleagues and leaders at UVA.

Theres been a very big push recently to better understand gravitational waves not only as a theoretical prediction or concept but to be able to directly detect them, said Phil Arras, chair of UVAs Department of Astronomy. That effort has opened up an entirely new window into the universe and given us a new way to check our theories about how stars evolve. Kents research has been very important for our understanding of that.

Despina Louca, chair of UVAs Department of Physics called Yagi a highly respected astrophysicist with a vast research portfolio.

Kent is an engaging educator and a sought-after mentor whose work has had tremendous impact across several physics disciplines, Louca added. He is paving the way to using machine learning to test general relativity while exploring astrophysical properties of neutron stars, and his work with UVA students building online games that integrate research and education will inspire young people around the world.

Professor Yagis work is remarkable, said Christa Acampora, dean of the College and Graduate School of Arts & Sciences, Were proud to have him as a member of our faculty, not only for the recognition hes receiving as he advances the boundaries of our understanding about the universe but also for his commitment to innovation in STEM education.

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The Quest for a Theory of Everything Scientists Put Einstein to the Test - SciTechDaily

In a stunning achievement in quantum physics, researchers have synchronized the shift of a quantized electronic energy level with atomic oscillations, achieving this at a speed exceeding a trillionth of a second.

This achievement, accomplished by physicists from the University of Regensburg, is akin to manipulating the height to which a ball is thrown.

However, this was done within the quantum realm where energy levels resemble steps on a ladder, each step representing a quantized energy value unique to quantum particles like electrons.

The significance of quantized energy levels is paramount in modern technology, underpinning the functionality of qubits in quantum computing, light-emitting quantum dots awarded the Nobel Prize in 2023, and other quantum devices.

These energy levels, however, are susceptible to alterations through interactions with other particles, presenting both a challenge and an opportunity for researchers aiming to harness quantum behaviors for advanced technologies.

Leveraging a state-of-the-art ultrafast microscope, the Regensburg team has accomplished the direct observation and control of how an electrons energy is adjusted by the atomic vibrations of its environment.

This was observed with unprecedented atomic resolution and at speeds previously deemed unattainable, marking a significant leap towards the realization of ultra-fast quantum technologies.

The researchers focused their study on atomically thin materials, specifically examining how the movement of such a material can influence discrete energy levels.

Their observations centered around a vacancy, a void created by the absence of an atom, within these two-dimensional crystals. These vacancies, akin to atoms, have distinct energy levels making them promising candidates for quantum computing qubits.

By inducing vibrations similar to those of a drums membrane on the atomic scale, the team discovered they could alter the energy level of a vacancy, effectively controlling it through the surrounding atomic movements.

These findings, detailed in Nature Photonics, could pave the way for future nanoelectronics and quantum computing technologies.

Overcoming numerous challenges, including achieving atomic resolution and capturing extremely rapid movements, the teams method integrated a scanning tunneling microscopes high energy and spatial resolution with custom-tailored ultrashort laser pulses.

This innovative approach allowed them to observe the dynamic shifts of energy levels in what can be likened to slow motion.

In summary, brilliant physicists at the University of Regensburg have set a new benchmark in quantum physics by intricately manipulating and observing the quantum states of electrons with unprecedented precision and speed.

This remarkable achievement deepens our understanding of the quantum world while opening a new realm ripe with possibilities for the development of advanced quantum technologies and materials.

Through their innovative approach and collaborative effort, they have paved the way for future breakthroughs that could revolutionize how we interact with and harness the power of quantum mechanics.

This astounding breakthrough promises a future where the once-theoretical aspects of quantum physics become the cornerstone of practical, real-world applications.

The collaborative effort, spearheaded by Carmen Roelcke, Lukas Kastner, and Yaroslav Gerasimenko, alongside the expertise of Jascha Repp, Rupert Huber, Maximilian Graml, and Jan Wilhelm, was crucial in deciphering the interaction between atomic movements and electronic energy levels.

The full study was published in the journal Nature Photonics.

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Vibrating atoms are seen 'tuning' the energy of a single electron - Earth.com