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For one of the first times, topological photons—light—has been combined with lattice vibrations, also known as phonons, to manipulate their propagation in a robust and controllable way. "We coupled helical photons with lattice vibrations in hexagonal boron nitride, creating a new hybrid matter referred to as phonon-polaritons," said Alexander Khanikaev, lead author and physicist with affiliation in CCNY's Grove School of Engineering. "It is half light and half vibrations. Since infrared light and lattice vibrations are associated with heat, we created new channels for propagation of light and heat together. Typically, lattice vibrations are very hard to control, and guiding...

Accelerators like RHIC and LHC routinely turn energy into matter by accelerating pieces of atoms near the speed of light and smashing them into one another. The 2012 discovery of the Higgs particle at the LHC is a notable example. At the time, the Higgs was the final unobserved particle in the Standard Model, a theory that describes the fundamental forces and building blocks of atoms. Impressive as it is, physicists know the Standard Model explains only about 4% of the matter and energy in the universe. The ions are nuclei of massive elements like gold or lead, and ion...

In a demonstration of Einstein’s E=mc2, collisions of light yielded electrons and positrons "Collide light with light, and poof, you get matter and antimatter. It sounds like a simple idea, but it turns out to be surprisingly hard to prove. A team of physicists is now claiming the first direct observation of the long-sought Breit-Wheeler process, in which two particles of light, or photons, crash into one another and produce an electron and its antimatter counterpart, a positron. Like a discussion from an introductory philosophy course, the detection’s significance hinges on the definition of the word “real.” Some physicists argue...

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 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...

In this mini world, the concepts of "before" and "after" dissolve, such that two events can both precede and succeed each other. In other words, event A can occur before event B, and event B can occur before event A... This idea, called a "quantum switch," was first proposed in 2009 by another team and has since been explored both theoretically and experimentally. Previous experiments showed event A could both precede and succeed event B, but the research couldn't say that these two scenarios were happening at the same place, said Cyril Branciard, co-author of this new study and a...

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...

Quantum information science and technology has emerged as a new paradigm for dramatically faster computation and secure communication in the 21st century. At the heart of any quantum system is the most basic building block, the quantum bit or qbit, which carries the quantum information that can be transferred and processed (this is the quantum analogue of the bit used in current information systems). The most promising carrier qbit for ultimately fast, long distance quantum information transfer is the photon, the quantum unit of light. The challenge facing scientists is to produce artificial sources of photons for various quantum information...

Now physicists at the University of Vienna in Austria have "virtually intertwined" or entangled two particles spinning faster than ever in opposite directions. Entanglement occurs when two particles remain connected so that actions performed on one affect the other, despite the distance between them. (Einstein referred to this eerie connection as "spooky action at a distance.") In the new study, Anton Fickler and his colleagues entangled two photons that had a high orbital angular momentum, a property that measures the twisting of a wave of light. In quantum physics, particles such as photons can behave as particles and waves. Such...

A fresh take on a classic experiment makes no progress in unifying quantum mechanics and relativity. If you ever want to get your head around the riddle that is quantum mechanics, look no further than the double-slit experiment. This shows, with perfect simplicity, how just watching a wave or a particle can change its behaviour. The idea is so unpalatable to physicists that they have spent decades trying to find new ways to test it. The latest such attempt, by physicists in Europe and Canada, used a three-slit version — but quantum mechanics won out again. In the standard double-slit...

TUSTIN, Calif., Sept. 7, 2007 -- An amplified photon thruster that could potentially shorten the trip to Mars from six months to a week has reportedly attracted the attention of aerospace agencies and contractors. Young Bae, founder of the Bae Institute in Tustin, Calif., first demonstrated his photonic laser thruster (PLT), which he built with off-the-shelf components, in December. The demonstration produced a photon thrust of 35 µN and is scalable to achieve much greater thrust for future space missions, the institute said. Applications include highly precise satellite formation flying configurations for building large synthetic apertures in space for earth...

Current theory is that nothing CAN travel faster than light (photons), and it is upon this that the theory of relativity rests. How about we change that definition to "nothing travels faster than light", ie that it is not impossible to exceed light speed, it is just that at the moment nothing does. Suppose a particle of light (photon) has some mass (otherwise it would not exist). Suppose we envisage a photon travelling at light speed. We are travelling in our turbocharged faster than light speed vehicle. We come up behind the photon and give it a little nudge. Does...

Astronomy Picture of the Day Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer. 2002 September 14 X-Ray Moon Credit: J. Schmitt et al., ROSAT Mission, MPE, ESA Explanation: This x-ray image of the Moon was made by the orbiting ROSAT (Röntgensatellit) Observatory in 1990. In this digital picture, pixel brightness corresponds to x-ray intensity. Consider the image in three parts: the bright hemisphere of the x-ray moon, the darker half of the moon, and the x-ray sky background. The bright lunar...