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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...

Scientists have for the first time observed quantum entanglement — a state in which particles intermingle, losing their individuality so they can no longer be described separately — between quarks. The feat, achieved at CERN, Europe’s particle-physics laboratory near Geneva, Switzerland, could open the door to further probes of quantum information in particles at high energies. Entanglement has been measured in particles such as electrons and photons for decades, but it is a delicate phenomenon and easiest to measure in low-energy, or ‘quiet’, environments, such as in the ultracold refrigerators that house quantum computers. Particle collisions, such as those between...

“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...

A recent study underscores the dynamic nature of black holes and extends similar thermodynamic characteristics to Extremely Compact Objects, advancing our comprehension of their behavior in quantum gravity scenarios.A paper titled "Universality of the thermodynamics of a quantum-mechanically radiating black hole departing from thermality," published in Physics Letters B highlights the importance of considering black holes as dynamical systems, where variations in their geometry during radiation emissions are critical to accurately describing their thermodynamic behavior.The study also suggests that extremely compact objects (ECOs) share these thermodynamic properties with black holes, regardless of their event horizon status. The significance of this...

A research group in China has shown that many entangled photons can be generated inside the myelin sheath that covers nerve fibers...It could explain the rapid communication between neurons, which so far has been thought to be below the speed of sound, too slow to explain how the neural synchronization occurs.

Sandia National Laboratories’ four-channel, silicon photonic single-sideband modulator chip, measuring 8 millimeters on each side and marked with a green Sandia thunderbird logo, sits inside packaging that incorporates optical fibers, wire bonds, and ceramic pins. Credit: Craig Fritz, Sandia National Laboratories ==================================================================== A milestone in quantum sensing is drawing closer, promising exquisitely accurate, GPS-free navigation. Peel apart a smartphone, fitness tracker or virtual reality headset, and inside you’ll find a tiny motion sensor tracking its position and movement. Bigger, more expensive versions of the same technology, about the size of a grapefruit and a thousand times more accurate, help navigate...

Scientists say they have created a new method of testing materials that allows predictions to be made about their ductility, which could lead to the production of virtually “unbreakable” metals for use with components in a variety of applications. Drawing from quantum mechanics principles, the new method allows for significant improvements by enhancing predictions about metals’ ability to be drawn out into thinner shapes while maintaining their strength. According to researchers involved with the discovery, the new method has proven very effective for metals used in high-temperature applications and could help industries like aerospace and other fields perform tests of...

An artist's impression of the experiment. (University of Southampton) ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Acting on a tiny particle levitating in a magnetic trap, physicists have just measured the smallest gravitational pull ever recorded. The particle weighed just 0.43 grams. And the strength of the gravitational force at play was on the scale of attonewtons (10-18 newtons). That's small enough to be right on the verge of the quantum realm, teasing the possibility of finally figuring out how classical physics and quantum mechanics interact. "For a century, scientists have tried and failed to understand how gravity and quantum mechanics work together," says physicist Tim...

Alain Aspect, John Clauser and Anton Zeilinger have won the 2022 Nobel Prize in Physics for groundbreaking experiments with entangled particles. The physicists Alain Aspect, John Clauser and Anton Zeilinger have won the 2022 Nobel Prize in Physics for experiments that proved the profoundly strange quantum nature of reality. Their experiments collectively established the existence of a bizarre quantum phenomenon known as entanglement, where two widely separated particles appear to share information despite having no conceivable way of communicating. Entanglement lay at the heart of a fiery clash in the 1930s between physics titans Albert Einstein on the one hand...

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...

Researchers have pioneered a technique for swiftly and efficiently reconstructing the full quantum state of entangled particles, utilizing advanced camera technology to visualize the wave function of two entangled photons in real time. The innovative method is exponentially faster than previous ones, taking minutes or seconds instead of days, and holds the potential for advancing quantum technology by enhancing quantum state characterization, quantum communication, and quantum imaging techniques. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ A new technique based on advanced camera technology demonstrates a rapid and efficient way to reconstruct the full quantum state of entangled particles. Researchers from the University of Ottawa, working together...

In the most massive test to date, physicists have probed a major paradox in quantum mechanics and found it still holds even for clouds of hundreds of atoms.Using two entangled Bose-Einstein condensates, each consisting of 700 atoms, a team of physicists co-led by Paolo Colciaghi and Yifan Li of the University of Basel in Switzerland has shown that the Einstein-Podolsky-Rosen (EPR) paradox scales up.The researchers say this has important implications for quantum metrology – the study of measuring things under quantum theory...One of the tools we use to close one of the gaps is quantum mechanics, a theory that arose...

Over the past few decades, scientists have made incredible progress in understanding and manipulating biological systems at increasingly small scales, from protein folding to genetic engineering. And yet, the extent to which quantum effects influence living systems remains barely understood...Quantum effects are phenomena that occur between atoms and molecules that can't be explained by classical physics...Instead, tiny objects behave according to a different set of laws known as quantum mechanics.

Quantum machine - Inside the 30-meter tube. (ETH Zurich/Daniel Winkler) Albert Einstein wasn't entirely convinced about quantum mechanics, suggesting our understanding of it was incomplete. In particular, Einstein took issue with entanglement, the notion that a particle could be affected by another particle that wasn't close by. Experiments since have shown that quantum entanglement is indeed possible and that two entangled particles can be connected over a distance. Now a new experiment further confirms it, and in a way we haven't seen before. In the new experiment, scientists used a 30-meter-long tube cooled to close to absolute zero to run...

Imagine you are 40-something and want to go on a date looking like you did 20 years ago. This is impossible in the classical physical world but not in the quantum world, which refers to the subatomic particles that are the foundation for all reality...The team published papers in Physical Review X, Quantum, Arxiv, Physical Review Letters and Optica on theoretical research and experiments proving it's possible to "accelerate, decelerate and reverse the flow of time within arbitrary, even uncontrolled quantum systems."

University of Central Florida College of Optics and Photonics researchers achieved the first observation of de Broglie-Mackinnon wave packets by exploiting a loophole in 1980’s-era laser physics theorem. A research paper by CREOL and Florida Photonics Center of Excellence professor Ayman Abouraddy and research assistant Layton Hall ’22MS has been published in the peer-reviewed scientific journal, Nature Physics. Observation of optical de Broglie–Mackinnon wave packets highlights the team’s research using a class of pulsed laser beams they call space-time wave packets. In an interview with Dr. Abouraddy, he provides more insight into his team’s research and what it may hold...

For decades physicists have tried to rectify the Standard Model of Particle Physics, which is great at describing the behavior of particles, interactions, and quantum processes on the micro scale, with gravity...the Standard Model, as it is currently constructed, fails to account for gravity at this extremely small scale. ...a number of mathematical models have been proposed that would unify these disparate phenomena, including something called string theory [and] a number of these models feature elements that can be tested in a lab setting. One is known as the Pauli exclusion principle. Pauli exclusion basically means that no two electrons...

1. A cat can be dead and alive Obviously, a cat is nothing like an individual photon in a controlled lab environment, it is much bigger and more complex. Any coherence that the trillions upon trillions of atoms that make up the cat might have with each other is extremely short-lived. This does not mean that quantum coherence is impossible in biological systems, just that it generally won't apply to big creatures such as cats or a human. 2. Simple analogies can explain entanglement Quantum particles are just mysteriously correlated in ways we can't describe with everyday logic or language...

Scientists discover exotic quantum state at room temperature An illustration depicting a topological insulator in action. - Shafayat Hossain and M. Zahid Hasan of Princeton University For the first time, physicists have observed novel quantum effects in a topological insulator at room temperature. Researchers at Princeton found that a material known as a topological insulator, made from the elements bismuth and bromine, exhibit specialized quantum behaviors normally seen only under extreme experimental conditions of high pressures and temperatures near absolute zero. The finding opens up a new range of possibilities for the development of efficient quantum technologies, such as spin-based,...

A new conjecture in physics challenges the leading “theory of everything.”On June 25, Timm Wrase awoke in Vienna and groggily scrolled through an online repository of newly posted physics papers. One title startled him into full consciousness. The paper, by the prominent string theorist Cumrun Vafa of Harvard and his collaborators, conjectured a simple formula dictating which kinds of universes are allowed to exist and which are forbidden, according to string theory. The leading candidate for a “theory of everything” weaving the force of gravity together with quantum physics, string theory defines all matter and forces as vibrations of tiny...