First Evidence Of A Correction To The Speed of Light — The Physics arXiv Blog — Medium

First Evidence Of A Correction To The Speed of Light — The Physics arXiv Blog — Medium: Because all previous speed-of-light calculations have relied only on general relativity, they do not take into account the tiny effects of quantum mechanics. But these effects are significant over such long distances and through such a large mass as the Milky Way, says Franson...

Franson’s idea is that the gravitational potential must influence the electron-positron pair because they have mass. “Roughly speaking, the gravitational potential changes the energy of a virtual electron-positron pair, which in turn produces a small change in the energy of a photon,” he says. “This results in a small correction to the angular frequency of a photon and thus its velocity.”

A Mathematical Proof That The Universe Could Have Formed Spontaneously From Nothing — The Physics arXiv Blog — Medium

A Mathematical Proof That The Universe Could Have Formed Spontaneously From Nothing — The Physics arXiv Blog — Medium: The new proof is based on a special set of solutions to a mathematical entity known as the Wheeler-DeWitt equation...

In each of these cases, they find a solution in which the bubble can expand exponentially and thereby reach a size in which a universe can form—a Big Bang...

Fastest rotating man-made object created

Fastest rotating man-made object created: To do this they manufactured a microscopic sphere of calcium carbonate only 4 millionths of a metre in diameter. The team then used the miniscule forces of laser light to hold the sphere with the radiation pressure of light...
They exploited the property of polarisation of the laser light that changed as the light passed through the levitating sphere, exerting a small twist or torque.
Placing the sphere in vacuum largely removed the drag (friction) due to any gas environment, allowing the team to achieve the very high rotation rates...

"I am intrigued with the prospect of extending this to multiple trapped particles and rotating systems. We may even be able to shed light on the area of quantum friction – that is – does quantum mechanics put the brakes on the motion or spinning particle even though we are in a near perfect vacuum with no other apparent sources of friction?"

Scientists examine nothing, find something - CSMonitor.com

Scientists examine nothing, find something - CSMonitor.com: They suggest that the impedance of a vacuum – another electromagnetic 'constant' whose value depends on the speed of light – itself depends only on the electric charge of the particles in the vacuum, and not their masses.

If their hypothesis is correct, it answers our question of where the speed of light comes from: It emerges from the total number of charged particles in the universe.

Predicted state of atomic collapse seen for first time - MIT News Office

Predicted state of atomic collapse seen for first time - MIT News Office: What the new Science paper reports is that atoms sitting on a sheet of graphene — a two-dimensional structure composed of carbon atoms linked in a chicken-wire-like mesh of hexagonal bonds — exactly mimic the properties of atomic nuclei, and can be manipulated to recreate and observe complex atomic phenomena. The key is that while electrons move through graphene as relativistic particles — as though they were massless, even though they actually do have mass — their motion is 300 times slower than that of true massless particles. As a result, the expected phenomenon of collapse should take place at one-three-hundredth the normal nuclear charge — putting it well within reach of experimental observations.

To simulate atomic nuclei, the researchers used pairs of calcium atoms on the graphene surface; they were able to manipulate these pairs (called dimers) on the surface using the probe tip of a scanning tunneling microscope. As soon as three dimers were pushed close together, the surrounding field of electrons showed a specific spectrum of resonances that precisely matched the decades-old predictions of atomic collapse. The observed resonances persisted in a four-dimer and five-dimer artificial nucleus.

Topology: The Secret Ingredient In The Latest Theory of Everything

Topology: The Secret Ingredient In The Latest Theory of Everything: Today, Wen combines topology, symmetry and quantum mechanics in a new theory that predicts the existence of new states of matter, unifies various puzzling phenomena in solid state physics and allows the creation artificial vacuums populated with artificial photons and electrons...

Xiao-Gang Wen's approach is to explore the properties of matter when the topological links between particles become much more general and complex. He generalises these links, thinking of them as strings that can connect many  particles together. In fact, he considers the way many strings can form net-like structures that have their own emergent properties...
That makes string nets a kind of "quantum ether" through which electromagnetic waves travel. That's a big claim.

Harnessing the quantum power of empty space

Harnessing the quantum power of empty space: There is a more fundamental objection, however. The litany of theoretical predictions gradually being turned into experimental reality invites a simple conclusion: vacuum fluctuations are real, and they are what is responsible for what we call Casimir effects. But not all physicists buy that.


Their unease lies in calculations done by Casimir and Polder even before they settled on vacuum fluctuations as the explanation for the weakened van der Waals force. These showed that much the same weakening could be achieved simply by taking into account the finite time the force takes to be transmitted over large enough distances, such as between two plates separated by tens or hundreds of nanometres. That idea was revived and bolstered by calculations in the 1970s by the Nobel-prizewinning physicist Julian Schwinger. He never believed in the reality of vacuum fluctuations and developed a version of quantum field theory, which he called source theory, to do away with them. In this picture, the Casimir effect pops out just by taking into account the quantum interaction of charged matter, with no vacuum action at all.

Robert Jaffe, a particle theorist at the Massachusetts Institute of Technology, suggests the only reason the vacuum interpretation has gained such currency is because its mathematics happens to be a lot simpler. "There is a flippant way people refer to the Casimir effect as evidence for real vacuum fluctuations," he says. "But there is no evidence that the vacuum fluctuations exist in the absence of matter". Similarly, other effects invoked as proof of their reality - the Lamb shift and the spontaneous emission of photons from atoms - can be described purely as the result of charge interactions.

Magnetic Fields Turn The Vacuum Into A Superconducting Superlens, Says Physicist� - Technology Review

Magnetic Fields Turn The Vacuum Into A Superconducting Superlens, Says Physicist� - Technology Review: Now Smolyaninov has turned his attention to the superconducting behaviour of the charged ρ mesons generated in a vacuum by a magnetic field. He points out that this superconducting state behaves exactly like a metamaterial, focusing light in exotic ways.

If this magnetic field varies in space in the right kind of way, it's quite possible for this superconducting state to focus light like a superlens. Equally it could also trap light like a black hole.
Nobody has created a magnetic field powerful enough to observe this effect on Earth but such fields must have existed elsewhere. Both Smolyaninov and Chernodub say that in the early Universe, just fractions of a second after the Big Bang, the fields must have been powerful enough to generate these superconducting states.

Dark matter may be an illusion caused by the quantum vacuum

Dark matter may be an illusion caused by the quantum vacuum: “I suggest a third way, without introducing dark matter and without modification of the law of gravity.”
His ideas (like those in the previous paper) rest on the key hypothesis that matter and antimatter are gravitationally repulsive, which is due to the fact that particles and antiparticles have gravitational charge of opposite sign...
“Concerning gravity, mainstream physics assumes that there is only one gravitational charge (identified with the inertial mass) while I have assumed that, as in the case of electromagnetic interactions, there are two gravitational charges: positive gravitational charge for matter and negative gravitational charge for antimatter,” Hajdukovic explained...
He also derives the famous Tully-Fisher relation as a consequence of the gravitational repulsion between matter and antimatter. This relation is an empirical law based on numerical data collected by numerous observations of galaxies and clusters of galaxies, and is still unexplained in the framework of dark matter hypotheses.

Vacuum has friction after all - space - 11 February 2011 - New Scientist

Vacuum has friction after all: The rate of deceleration also depends on temperature, since the hotter it is the more virtual photons pop in and out of existence, producing the friction. At room temperature, a 100-nanometre-wide grain of graphite, the kind that is abundant in interstellar dust, would take about 10 years to slow to about one-third of its initial speed. At 700 °C, an average temperature for hot areas of the universe, that same speed decrease would take only 90 days. In the cold of interstellar space, it would take 2.7 million years.

A Blueprint for a Quantum Propulsion Machine | MIT Technology Review

A Blueprint for a Quantum Propulsion Machine | MIT Technology Review: ...the quantum vacuum constantly interacts with magnetoelectric materials generating Lorentz forces. Most of the time, however, these forces sum to zero.

However, Feigel says there are four cases in which the forces do not sum to zero...

The first method is to rapidly aggregate a number of magnetoelectric nanoparticles, a process which influences the boundary conditions for higher frequency electromagnetic waves, generating a force.

The second is simply to rotate a group of magnetoelectric nanoparticles, which also generates a Lorentz force.

Either way, the result is a change in velocity. As Feigel puts it: “mechanical action of quantum vacuum on magneto-electric objects may be observable and have a significant value.”

The beauty of Feigel’s idea is that it can be easily tested. He suggests building an addressable array of magnetoelectric nanoparticles, perhaps made of a material such as FeGaO3 which has a magnetoelectric constant of 10^-4 in a weak magnetic field.