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In the early evening of Sunday, October 7, 1900 - 120 years ago - Max Planck found the functional form of the curve that we now know as the Planck distribution of black-body radiation. By my account, it was the birthdate of quantum mechanics. [In Comment #1 - a beautiful photo of Planck, Einstein, and Millikan at a dinner party]

Futurism: Your paper argues that the universe might fundamentally be a neural network. How would you explain your reasoning to someone who didn’t know very much about neural networks or physics? Vitaly Vanchurin: There are two ways to answer your question. The first way is to start with a precise model of neural networks and then to study the behavior of the network in the limit of a large number of neurons. What I have shown is that equations of quantum mechanics describe pretty well the behavior of the system near equilibrium and equations of classical mechanics describes pretty well...

John Horton Conway, a legendary mathematician who stood out for his love of games and for bringing mathematics to the masses, died on Saturday, April 11, in New Brunswick, New Jersey, from complications related to COVID-19. He was 82. Known for his unbounded curiosity and enthusiasm for subjects far beyond mathematics, Conway was a beloved figure in the hallways of PrincetonÂ’s mathematics building and at the Small World coffee shop on Nassau Street, where he engaged with students, faculty and mathematical hobbyists with equal interest. Conway, who joined the faculty in 1987, was the John von Neumann Professor in Applied...

The dynamics of electrons change ever so slightly on each interaction with a photon. Physicists at ETH Zurich have now measured such interplay in its arguably purest form—by recording the attosecond-scale time delays associated with one-photon transitions in an unbound electron. The photoelectric effect, whereby photons impinging on matter cause the emission of electrons, is one of the quintessential effects of quantum mechanics. Einstein famously explained the key mechanism underlying the phenomenon in 1905, earning him the 1921 Nobel Prize in Physics. He built on a concept introduced five years earlier by Max Planck: Electromagnetic energy is absorbed and emitted...

The theoretical notion of a 'quantum heat engine' has been around for several decades. It was first introduced around sixty years ago by Scovil and Schulz-DuBois, two physicists at Bell Labs who drew an analogy between three-level masers and thermal machines. In the years that followed, other researchers have developed a variety of theories building on the ideas of Scovil and Schulz-DuBois, introducing proposals of thermodynamic cycles at the quantum scale. Very recently, physicists have started testing some of these theories in experimental settings. One of these experiments was carried out by a team of researchers at the University of...

Quantum mechanics’ core assumption is that on the smallest scales, atomic properties are quantized...For example, an electron can be in a lowest-energy state, but if you add a little more energy, it doesn’t slowly transition into the new higher-energy state. Rather, it unpredictably snaps into the new state. If you’re not looking at it, the atom can take on intermediate states—but these aren’t midway points. The atom would be in both states at the same time, and then once you observed it, it would immediately snap into one state or the other. The team’s artificial atom is an experimental apparatus...

After the first-ever image of a black hole confirmed theories posited by Einstein, it's the late scientist Stephen Hawking's turn to have parts of his life's work vindicated. In a paper published in Nature, scientists say that have verified the scientist's namesake theory, Hawking Radiation, which hypothesized that black holes emit radiation from their surfaces due to a mix of different factors regarding quantum physics and gravity. To verify the theory, scientists at the Technion-Israel Institute of Technology turned to what sounds like mad science: creating their own black hole.

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...

One of the reasons why humans are handicapped in our understanding of reality is because of our reliance on the “scientific method”. It is a system based on observation. The problem with this method is that our understanding of reality is corrupted by the limits imposed by observation. Indeed, as well well know, it is the perception of the observer that changes our reality. This is a well understood rule. If you the reader, don’t “get it”, then you need to study quantum mechanics 101. For in the last two decades the entire foundation of our understanding of reality has...

Scientists think they've identified a previously unknown form of neural communication that self-propagates across brain tissue, and can leap wirelessly from neurons in one section of brain tissue to another – even if they've been surgically severed. The discovery offers some radical new insights about the way neurons might be talking to one another, via a mysterious process unrelated to conventionally understood mechanisms, such as synaptic transmission, axonal transport, and gap junction connections. "We don't know yet the 'So what?' part of this discovery entirely," says neural and biomedical engineer Dominique Durand from Case Western Reserve University. "But we do...

An old thought experiment now appears in a new light. In 1935 Erwin Schrödinger formulated a thought experiment designed to capture the paradoxical nature of quantum physics. A group of researchers led by Gerhard Rempe, Director of the Department of Quantum Dynamics at the Max Planck Institute of Quantum Optics, has now realized an optical version of Schrödinger's thought experiment in the laboratory. In this instance, pulses of laser light play the role of the cat. The insights gained from the project open up new prospects for enhanced control of optical states, that can in the future be used for...

Scientists from the Theory Department of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science (CFEL) in Hamburg, Germany have shown through theoretical calculations and computer simulations that the force between electrons and lattice distortions in an atomically thin two-dimensional superconductor can be controlled with virtual photons. This could aid the development of new superconductors for energy-saving devices and many other technical applications. The vacuum is not empty. It may sound like magic to laypeople but the problem has preoccupied physicists since the birth of quantum mechanics. The apparent void...

Columbia Engineering researchers have created the first flat lens capable of correctly focusing a large range of colors of any polarization to the same focal spot without the need for any additional elements. Only a micron thick, their revolutionary "flat" lens is much thinner than a sheet of paper and offers performance comparable to top-of-the-line compound lens systems. The findings of the team, led by Nanfang Yu, associate professor of applied physics , are outlined in a new study, published today by Light: Science & Applications. A conventional lens works by routing all the light falling upon it through different...

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...

“Harnessing the mysterious property that Albert Einstein called ‘spooky action at a distance’ is a crucial step toward exploiting quantum quirks for technology such as new kinds of sensors or computers,” the physicists said. “Entanglement is not just some academic curiosity; it’s also something you can harness as a basis for doing useful things with quantum mechanics,” Professor Clerk added. Entangled states are typically extremely fragile — especially so when they involve large objects. So Professor Clerk and his colleague, Dr. Matt Woolley from the University of New South Wales, developed a theoretical proposal for how to keep the motion...

For almost a century, physicists have wondered whether the most counterintuitive predictions of quantum mechanics (QM) could actually be true. Only in recent years has the technology necessary for answering this question become accessible, enabling a string of experimental results—including startling ones reported in 2007 and 2010, and culminating now with a remarkable test reported in May—that show that key predictions of QM are indeed correct. Taken together, these experiments indicate that the everyday world we perceive does not exist until observed, which in turn suggests—as we shall argue in this essay—a primary role for mind in nature. It is...

On Monday, a cargo delivery to the International Space Station will carry old-fashioned sextants, E. colibacteria and lasers that will create a temperature 10 billion times colder than the vacuum of space. … CAL is sending the space station an experimental physics package that holds an "ice chest"-like compartment filled with lasers and electronics; the interior will be able to reach a temperature10 billion times colder than the vacuum of space, according to a NASA statement. Within this instrument, the researchers will use laser cooling techniques and magnets to slow down atoms until they are almost entirely motionless. By studying...

The Difficult Birth of the "Many Worlds" Interpretation of Quantum Mechanics Hugh Everett, creator of this radical idea during a drunken debate more than 60 years ago, died before he could see his theory gain widespread popularity   By Adam Becker on March 21, 2018 Share on Facebook Share on Twitter Share on Reddit Email Print Share via Google+Stumble Upon Credit: Garik Barseghyan Pixabay Over several rounds of sherry late one night in the fall of 1955, the Danish physicist Aage Petersen debated the mysteries at the heart of quantum physics with two graduate students, Charles Misner and Hugh Everett, at Princeton University. Petersen was defending the...

'Delayed-choice' test, a first with spacefaring photons, affirms light can behave like a wave or a particle. Light is two-faced: Sometimes it behaves like a wave, sometimes like a particle. Now, scientists have shown that light’s shifty disposition persists even after trekking thousands of kilometers into space and back again, researchers report October 25 in Science Advances.Depending on how light is measured, it can either be particle-like, lighting up a camera pixel, for example, or wavelike, interfering with other waves like ripples on the surface of water. It’s one of the many oddities of quantum mechanics. Before light is measured,...

Perhaps one of the most intriguing and interesting phenomena in quantum physics is what Einstein referred to as a "spooky action at a distance" - also known as quantum entanglement. This quantum effect is behind what makes quantum computers work, as quantum bits (qubits) generally rely on entanglement to process data and information. It's also the working theory behind the possibility of quantum teleportation. The long and short of it is this: entangled particles affect one another regardless of distance, where a measurement of the state of one would instantly influence the state of the other. However, it remains "spooky"...