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Seeing our world through the eyes of a migratory bird would be a rather spooky experience. Something about their visual system allows them to 'see' our planet's magnetic field, a clever trick of quantum physics, and biochemistry that helps them navigate vast distances. Now, for the first time ever, scientists from the University of Tokyo have directly observed a key reaction hypothesised to be behind birds', and many other creatures', talents for sensing the direction of the planet's poles. Importantly, this is evidence of quantum physics directly affecting a biochemical reaction in a cell – something we've long hypothesised but...

Time travel has long captured the human imagination, from its appearances in science fiction fantasies to its profound implications in modern theoretical physics. Now, a recent study by Dr. Lorenzo Gavassino, a theoretical and mathematical physicist at Vanderbilt University, delves into the enigmatic nature of time travel involving time loops to examine their profound implications for quantum mechanics, entropy, and human experience. Dr. Gavassino’s findings, published in Classical and Quantum Gravity, present a strikingly different picture of time travel. They reveal that traveling through such time loops would prevent many classical time travel paradoxes, including the infamous “grandfather paradox.” “It...

Rice University physicists have mathematically unveiled the possibility of paraparticles, which defy the traditional binary classification of particles into bosons and fermions. Their research, which delves into the realms of abstract algebra and condensed matter, hints at groundbreaking applications in quantum computing and information systems, suggesting an exciting, albeit speculative, future for new material properties and particle behavior. Breaking Conventional Particle Categories Since the early days of quantum mechanics, scientists have believed that all particles fall into one of two categories — bosons or fermions — defined by their distinct behaviors. However, recent research by Rice University physicist Kaden Hazzard...

A research team from the University of Science and Technology of China (USTC) of the Chinese Academy of Sciences (CAS), led by Prof. Jianwei Pan, Qiang Zhang, and Kai Chen, in collaboration with CHEN Jingling from Nankai University, has achieved the loophole-free test of Hardy's paradox for the first time. The team successfully demonstrated Hardy's nonlocality, closing both the detection efficiency loophole and the locality loophole...Hardy's paradox, introduced by Lucien Hardy in the 1990s, offers a simplified test of local realism—the classical idea that physical properties exist independently of observation and that no signals exceed the speed of light. This...

“We proved that the Einstein field equation from general relativity is actually a relativistic quantum mechanical equation,” the researchers note in their study. In simple words, this new framework connects the science that governs the macroscopic world with that of the microscopic world. Therefore, it has the potential to explain every physical phenomenon known to humanity ranging from the mysterious dark matter in space to the photons emitted by your phone’s flashlight. “To date, no globally accepted theory has been proposed to explain all physical observations,” the researchers added. They claim that their theory can challenge the foundations of physics...

The Laser Interferometer Gravitational-Wave Observatory (LIGO) has improved its detection of cosmic events by overcoming quantum noise through advanced “squeezing” technology. This breakthrough will increase its detection rate by 60 percent and pave the way for advancements in quantum technology and physics. Researchers using LIGO achieved a landmark in quantum squeezing. In 2015, the Laser Interferometer Gravitational-Wave Observatory, or LIGO, made history when it made the first direct detection of gravitational waves, or ripples in space and time, produced by a pair of colliding black holes. Since then, the U.S. National Science Foundation (NSF)-funded LIGO and its sister detector in...

Three scientists jointly won this year's Nobel Prize in physics on Tuesday for their work on quantum information science that has significant applications, for example in the field of encryption. Alain Aspect, John F. Clauser and Anton Zeilinger were cited by the Royal Swedish Academy of Sciences for discovering the way that particles known as photons can be linked, or "entangled," with each other even when they are separated by large distances. "Quantum information science is a vibrant and rapidly developing field," said Eva Olsson, a member of the Nobel committee. "It has broad and potential implications in areas such...

Two teams of researchers working independently have shown the viability of using neutral atoms to create quantum circuits—both have published outlines of their work in the journal Nature. One of the groups, with members from the University of Wisconsin, Madison, ColdQuanta and Riverlane, successfully ran an algorithm on a cold atom quantum computer for the first time. The second group, with members from Harvard, MIT, QuEra Computing Inc., the University of Innsbruck and the Austrian Academy of Sciences, showed that it was possible to build a quantum processor based on coherent transport of entangled atom arrays. Hannah Williams, with Durham...

Cuprous oxide crystal. (University of St Andrews) One of the ways we can fully realize the potential of quantum computers is by basing them on both light and matter – this way, information can be stored and processed, but also travel at the speed of light. Scientists have just taken a step closer to this goal, by successfully producing the largest hybrid particles of light and matter ever created. These quasiparticles, known as Rydberg polaritons, were made with the help of a piece of stone containing cuprous oxide (Cu2O) crystals from an ancient deposit in Namibia, one of the few...

To make a space crystal, you need the immense pressures of the Earth’s surface bearing down on minerals and magma. But to make a time crystal, you need esoteric equations and ridiculously precise lasers. At least, that’s how physicists shaped the first self-standing time crystal in a lab last year. Now, they’ve turned into an even more tangible object by creating a time crystal from common elements that can withstand room temperature. If you’re wondering what a time crystal is (outside of pulp science fiction), most physicists also had the same question until pretty recently. It’s a form of matter...

Quantum teleportation of an unknown input state from an outside source onto a quantum node is considered one of the key components of long-distance quantum communication protocols. It has already been demonstrated with pure photonic quantum systems as well as atomic and solid-state spin systems linked by photonic channels. Now, a team of researchers from the Netherlands, Brazil and China has demonstrated quantum teleportation of a polarization-encoded optical input state onto the joint state of a pair of nanomechanical resonators. “The use of optomechanical devices is a breakthrough because they can be designed to operate at any optical wavelength, including...

Some of the greatest unanswered questions about the nature of the universe are related to light, the vacuum (i.e. space where neither matter nor radiation exists), and their relationship with time. In the past, physicists and philosophers have addressed a variety of complex questions, for instance, what is the nature of the vacuum, and how is the propagation of light connected to the passing of time? Researchers at the University of Konstanz have recently carried out a study exploring the quantum states of light and vacuum fluctuations, as well as their interplay with time. Their paper, published in Nature Physics,...

For the first time, researchers have performed a version of the famous double-slit experiment with antimatter particles.The double-slit experiment demonstrates one of the fundamental tenets of quantum physics: that pointlike particles are also waves. In the standard version of the experiment, particles travel through a pair of slits in a solid barrier. On a screen on the other side, an interference pattern typical of waves appears. Crests and troughs emerging from each slit reinforce each other or cancel each other out as they overlap, creating alternating bands of high and low particle density on the screen.This kind of experiment has...

The laws of physics are such that one photon just passes by another with zero interaction. But in a new experiment inside the world's most powerful atom smasher, researchers got a glimpse of the impossible: photons bumping into each other. The answer lies in one of the most inscrutable and yet delicious aspects of modern physics, and it goes by the funky name of quantum electrodynamics. In this picture of the subatomic world, the photon isn't necessarily a photon. Well, at least, it's not always a photon. Particles like electrons and photons and all the other -ons continually flip back...

Something isn't quite right in the universe. At least based on everything physicists know so far. Stars, galaxies, black holes and all the other celestial objects are hurtling away from each other ever faster over time. Past measurements in our local neighborhood of the universe find that the universe is exploding outward faster than it was in the beginning. That shouldn't be the case, based on scientists' best descriptor of the universe. If their measurements of a value known as the Hubble Constant are correct, it means that the current model is missing crucial new physics, such as unaccounted-for fundamental...

Quantum physics sets the laws that dominate the universe at a small scale. The ability to harness quantum phenomena could lead to machines like quantum computers, which are predicted to perform certain calculations much faster than conventional computers. One major problem with building quantum processors is that the tracking and controlling quantum systems in real time is a difficult task because quantum systems are overwhelmingly fragile: Manipulating these systems carelessly introduces significant errors in the final result. New work by a team at Aalto could lead to precise quantum computers. The researchers report controlling quantum phenomena in a custom-designed electrical...

Entanglement is one of the most confusing aspects of quantum mechanics — a field of physics that isn't exactly known to be clear-cut, sensible, common-sense and easy-to-understand.  Even Albert Einstein himself was flummoxed by the surprising behavior of microscopic particles, and he firmly believed that we were fundamentally misunderstanding the universe with quantum mechanics. It turns out that Einstein was wrong, but it's going to take a while to explain where he went wrong and what's really going on in the quantum realm. Head of state One of the most important lessons from quantum mechanics is that we have to...

The 4th International Conference on Quantum Technologies held in Moscow last month was supposed to put the spotlight on Google, who were preparing to give a lecture on a 49-qubit quantum computer they have in the works. A morning talk presented by Harvard University’s Mikhail Lukin, however, upstaged that evening’s event with a small announcement of his own – his team of American and Russian researchers had successfully tested a 51-qubit device, setting a landmark in the race for quantum supremacy. Quantum computers are considered to be part of the next generation in revolutionary technology; devices that make use of...

Scientists have completed the first teleportation of an object from Earth to a satellite orbiting more than 300 miles away. Alas, those of you expecting Scotty to beam them up soon will be sorely disappointed - the object teleported was merely a single photon. While the experiment doesn't bring us any closer to teleporting matter, it is a huge leap forward for quantum physics. The team of Chinese researchers behind the successful teleportation came together from a number of disciplines and included quantum physicists as well as rocket scientists. In 2016, they launched a satellite called Micius, named after Chinese...

‘Binary and absolute differences’ are ‘exploitative’ A feminist academic affiliated with the University of Arizona has invented a new theory of “intersectional quantum physics,” and told the world about it in a journal published by Duke University Press. Whitney Stark argues in support of “combining intersectionality and quantum physics” to better understand “marginalized people” and to create “safer spaces” for them, in the latest issue of The Minnesota Review. Because traditional quantum physics theory has influenced humanity’s understanding of the world, it has also helped lend credence to the ongoing regime of racism, sexism and classism that hurts minorities, Stark...