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'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"...

We are living inside a Universe that’s so complex that if we can grasp what’s happening for a moment, we’ll fall down on our knees and cry in surrender to its marvelous beauty! Science just barely starts to scratch the surface to the nature of reality and still, its discoveries are more shocking than we were able to imagine. It proves of quantum entanglement, unified field of consciousness, free energy, superhuman abilities, singularity, parallel universes and alternate realities. All of this is so mind boggling that you would never think a kid can understand. But maybe we need a kid,...

Physicists reveal sensational findings which could allow science fiction dreams to become reality Professor Howard Wiseman and Dr Michael Hall, from Griffith University’s Centre for Quantum Dynamics, claim that the idea of parallel universes is more than just science fiction. Fellow researcher Dr Dirk-Andre Deckert, from the University of California, helped further the researchers’ theory, which goes against almost all conventional understanding of space and time. If there really are multiple, interacting universes, then it would be possible for time travellers to visit Earth, and every imaginable scenario would be played out in a parallel universe at some point. The...

Why quantum mechanics might need an overhaul by Tom Siegfried 3:37pm, November 4, 2016 Nobel laureate Steven Weinberg says current debates suggest need for new approach to comprehend reality SAN ANTONIO ? Quantum mechanics is science’s equivalent of political polarization. Voters either take sides and argue with each other endlessly, or stay home and accept politics as it is. Physicists either just accept quantum mechanics and do their calculations, or take sides in the never-ending debate over what quantum mechanics is actually saying about reality. Steven Weinberg used to be happy with quantum mechanics as it is and didn’t worry...

Schrödinger's cat now has a second box to play in, thanks to an international team of physicists that has created a two-mode "Schrödinger's cat state" for the first time. The experiment brings together two purely quantum properties, in that the "cat" (i.e. the photons) is simultaneously "alive and dead" (in a superposition of states) while also in two locations at once (the two boxes are entangled with one another).

An experiment claims to have invalidated a decades-old criticism against pilot-wave theory, an alternative formulation of quantum mechanics that avoids the most baffling features of the subatomic universe. Of the many counterintuitive features of quantum mechanics, perhaps the most challenging to our notions of common sense is that particles do not have locations until they are observed. This is exactly what the standard view of quantum mechanics, often called the Copenhagen interpretation, asks us to believe. Instead of the clear-cut positions and movements of Newtonian physics, we have a cloud of probabilities described by a mathematical structure known as a...

You already know that water can have three states of matter: solid, liquid and gas. But scientists at the Oak Ridge National Lab (ORNL) have discovered that when it's put under extreme pressure in small spaces, the life-giving liquid can exhibit a strange fourth state known as tunneling. The water under question was found in super-small six-sided channels in the mineral beryl, which forms the basis for the gems aquamarine and emerald. The channels measure only about five atoms across and function basically as cages that can each trap one water molecule. What the researchers found was that in this...

In "Star Trek," a transporter can teleport a person from one location to a remote location without actually making the journey along the way. Such a transporter has fascinated many people. Quantum teleportation shares several features of the transporter and is one of the most important protocols in quantum information. In a recent study, Prof. Tongcang Li at Purdue University and Dr. Zhang-qi Yin at Tsinghua University proposed the first scheme to use electromechanical oscillators and superconducting circuits to teleport the internal quantum state (memory) and center-of-mass motion state of a microorganism. They also proposed a scheme to create a...

Researchers have written quantum code on a silicon chip for the first time And so it begins... FIONA MACDONALD 17 NOV 2015           For the first time, Australian engineers have demonstrated that they can write and manipulate the quantum version of computer code on a silicon microchip. This was done by entangling two quantum bits with the highest accuracy ever recorded, and it means that we can now start to program for the super-powerful quantum computers of the future.Engineers code regular computers using traditional bits, which can be in one of two states: 1 or 0. Together, two bits...

Light behaves both as a particle and as a wave. Since the days of Einstein, scientists have been trying to directly observe both of these aspects of light at the same time. Now, scientists at EPFL have succeeded in capturing the first-ever snapshot of this dual behavior. Quantum mechanics tells us that light can behave simultaneously as a particle or a wave. However, there has never been an experiment able to capture both natures of light at the same time; the closest we have come is seeing either wave or particle, but always at different times. Taking a radically different...

Photons generally do not interact with each other in free space but instead one passes through the other with no effect to either one. Vienna University of Technology researchers have made a significant and groundbreaking discovery in the field of quantum mechanics. A team of researchers has developed some unique hardware, which enable photons to interact. This hardware is composed of micro-thin fiber made of glass, which in turn attached to a device called a resonator. The photon particle light can enter the resonator, moves in a circular fashion and then returns to the glass fiber. This change in pathways...

In 1909, Ernest Rutherford, Hans Geiger and Ernest Marsden took a piece of radium and used it to fire charged particles at a sheet of gold foil. They wanted to test the then-dominant theory that atoms were simply clusters of electrons floating in little seas of positive electrical charge (the so-called ‘plum pudding’ model). What came next, said Rutherford, was ‘the most incredible event that has ever happened to me in my life’. Despite the airy thinness of the foil, a small fraction of the particles bounced straight back at the source – a result, Rutherford noted, ‘as incredible as...

Schrödinger's cat is the poster child for quantum weirdness. Now it has been immortalised in a portrait created by one of the theory's strangest consequences: quantum entanglement. These images were generated using a cat stencil and entangled photons. The really spooky part is that the photons used to generate the image never interacted with the stencil, while the photons that illuminated the stencil were never seen by the camera.

For nearly a century, “reality” has been a murky concept. The laws of quantum physics seem to suggest that particles spend much of their time in a ghostly state, lacking even basic properties such as a definite location and instead existing everywhere and nowhere at once. Only when a particle is measured does it suddenly materialize, appearing to pick its position as if by a roll of the dice. This idea that nature is inherently probabilistic — that particles have no hard properties, only likelihoods, until they are observed — is directly implied by the standard equations of quantum mechanics....

Albert Einstein once told a friend that quantum mechanics doesn't hold water in his scientific world view because "physics should represent a reality in time and space, free from spooky actions at a distance." That spooky action at a distance is entanglement, a quantum phenomenon in which two particles, separated by any amount of distance, can instantaneously affect one another as if part of a unified system. Now, scientists have successfully hijacked that quantum weirdness -- doing so reliably for the first time -- to produce what many sci-fi fans have long dreamt up: teleportation. No, not beaming humans aboard...

Physicists have proposed an experiment that could force us to make a choice between extremes to describe the behaviour of the Universe. The proposal comes from an international team of researchers from Switzerland, Belgium, Spain and Singapore, and is published today in Nature Physics. It is based on what the researchers call a 'hidden influence inequality'. This exposes how quantum predictions challenge our best understanding about the nature of space and time, Einstein's theory of relativity. "We are interested in whether we can explain the funky phenomena we observe without sacrificing our sense of things happening smoothly in space and...

n March 2012, Joseph Polchinski began to contemplate suicide — at least in mathematical form. A string theorist at the Kavli Institute for Theoretical Physics in Santa Barbara, California, Polchinski was pondering what would happen to an astronaut who dived into a black hole. Obviously, he would die. But how? According to the then-accepted account, he wouldn’t feel anything special at first, even when his fall took him through the black hole’s event horizon: the invisible boundary beyond which nothing can escape. But eventually — after hours, days or even weeks if the black hole was big enough — he...

Ex nihilo: Dynamical Casimir effect in metamaterial converts vacuum fluctuations into real photons March 8, 2013 by Stuart Mason Dambrot Copyright © PNAS, doi:10.1073/pnas.1212705110 (Phys.org) —In the strange world of quantum mechanics, the vacuum state (sometimes referred to as the quantum vacuum, simply as the vacuum) is a quantum system's lowest possible energy state. While not containing physical particles, neither is it an empty void: Rather, the quantum vacuum contains fluctuating electromagnetic waves and so-called virtual particles, the latter being known to transition into and out of existence. In addition, the vacuum state has zero-point energy – the lowest quantized...

Scientists create never-before-seen form of matter Photons with strong mutual attraction in a quantum nonlinear medium. Harvard and MIT scientists are challenging the conventional wisdom about light, and they didn't need to go to a galaxy far, far away to do it. Working with colleagues at the Harvard-MIT Center for Ultracold Atoms, a group led by Harvard Professor of Physics Mikhail Lukin and MIT Professor of Physics Vladan Vuletic have managed to coax photons into binding together to form molecules – a state of matter that, until recently, had been purely theoretical. The work is described in a September 25...