•April 17, 2017 • Leave a Comment
“The researchers calculated that firing a short laser pulse at graphene could instantaneously trigger a ‘population reversal,’ switching electrons to holes and vice versa. This inversion of behavior is ‘effectively a propagation back in time,’ Richter said. Such a quantum time mirror could be made with current state-of-the-art technology, the researchers added.
Although the work is not intended to test the limits of time reversal, such fundamental restrictions may appear ‘once the experimental drawbacks are surmounted one by one,’ said quantum physicist Horacio Pastawski at the National University of Córdoba in Argentina, who did not participate in this study. He noted his own research explores how time reversal may become impossible once a system becomes complex and chaotic enough.
Richter stressed this quantum time mirror only works for relatively tiny systems protected from environmental disturbances. ‘It’s completely impossible to reverse time this way with, say, a person,’ he said. ‘Still, an interesting future direction one may ask is how large a system could be made that can experience reversal with a quantum time mirror.'”
Zaps from a Laser Could ‘Reverse Time’ on the Quantum Scale – Inside Science
•April 10, 2017 • Leave a Comment
“The equation is deceptively simple: ER = EPR.
It’s not made up of numerical values, but instead represents the names of some key players in theoretical physics.
On the left side of the equation, the ER stands for Einstein and Nathan Rosen,and refers to a 1935 paper they wrote together describing wormholes, known technically as Einstein-Rosen bridges.
On the right side of the equation, EPR stands for Einstein, Rosen and Boris Podolsky, who co-wrote another paper that year describing quantum entanglement.”
This New Equation Could Unite The Two Biggest Theories in Physics – Futurism
•April 5, 2017 • Leave a Comment
“’We know from very precise supernova observations that the universe is accelerating, but at the same time we rely on coarse approximations to Einstein’s equations which may introduce serious side-effects, such as the need for dark energy, in the models designed to fit the observational data.’
To test this the researchers constructed a computer simulation to compare a standard cosmological model (with normal matter, dark energy, and the equally mysterious dark matter) with one that only had dark matter and normal matter. The requirement was that the latter one, known as the Avera (Average Expansion Rate Approximation) model, has the same critical density as the standard model.
The simulations show a good agreement between each other and between the observations both in the early and recent universe. The Avera model does actually better match the apparent discrepancy between the local and past expansion rates of the universe.”
Dark Energy May Not Actually Exist – IFLScience!
•March 23, 2017 • Leave a Comment
“Researchers estimate that it took the equivalent energy of 100 million supernovas exploding simultaneously to jettison the black hole. The most plausible explanation for this propulsive energy is that the monster object was given a kick by gravitational waves unleashed by the merger of two hefty black holes at the center of the host galaxy.
… Hubble’s observations of the wayward black hole surprised the research team. ‘When I first saw this, I thought we were seeing something very peculiar,’ said team leader Marco Chiaberge of the Space Telescope Science Institute (STScI) and Johns Hopkins University, in Baltimore, Maryland. ‘When we combined observations from Hubble, the Chandra X-ray Observatory, and the Sloan Digital Sky Survey, it all pointed towards the same scenario. The amount of data we collected, from X-rays to ultraviolet to near-infrared light, is definitely larger than for any of the other candidate rogue black holes.'”
Gravitational wave kicks monster black hole out of galactic core – Phys.org
•February 21, 2017 • 5 Comments
“While physicists have debated about the nature of the quantum state since the early days of quantum theory (with, most famously, Bohr being in favor of the ontic interpretation and Einstein arguing for the epistemic one), most modern evidence has supported the view that the quantum state does indeed represent reality.
Philosophically, this interpretation can be hard to swallow, as it means that the many counterintuitive features of quantum theory are properties of reality, and not due to limitations of theory. One of the most notable of these features is superposition. Before a quantum object is measured, quantum theory says that the object simultaneously exists in more than one state, each with a particular probability. If these states are ontic, it means that a particle really does occupy two states at once, not merely that it appears that way due to our limited ability to prepare particles, as in the epistemic view…”
Proposed test would offer strongest evidence yet that the quantum state is real – Phys.org
•February 16, 2017 • Leave a Comment
“Scientists recently found parts of the brain which may form a circuit that provides consciousness. But how did it come about? A group of scientists from France and Canada believe that consciousness may have arisen in response to entropy. Our brains, just like any other system, are hurdling towards the end. Consciousness, these scientists argue, is a byproduct of that process…
‘We find a surprisingly simple result,’ they wrote. ‘Normal wakeful states are characterized by the greatest number of possible configurations of interactions between brain networks, representing highest entropy values.’ Consciousness in this view isn’t due to connectivity in and of itself, but how many different ways the brain can connect certain bundles of neurons to others. Due to the presence of high entropy, these scientists believe that to maximize the exchange of information between neurons, consciousness arose as an ’emergent property,’ helping to improve survival, but leading to a higher rate of entropy as a result.’
New Theory Suggests That Consciousness Is a Byproduct of Entropy – Big Think
•February 5, 2017 • Leave a Comment
“It’s no longer just a wild theory. Two independent teams of physicists have followed a recipe to build the world’s first versions of an enigmatic form of matter – time crystals.
MIT physicist and Nobel laureate Frank speculated about the existence of time crystals in 2012, while teaching a class on ordinary crystals, such as salt, or snowflakes. In a typical crystal, the atoms or molecules are tightly arranged in regularly repeating patterns in three-dimensional space, resembling a lattice.
Wilczek thought it might be possible to create a similar crystal-like structure in time, which is treated as a fourth dimension under relativity. Instead of regularly repeating rows of atoms, a time crystal would exhibit regularly repeating motion.
Many physicists were sceptical, arguing that a time crystal whose atoms could loop forever, with no need for extra energy, would be tantamount to a perpetual motion machine – forbidden by the laws of physics.
Wilczek countered that a time crystal was more akin to a superconductor in which electrons flow with no resistance, and in theory could do so forever without the need to add energy to the system. In a time crystal, electrons would travel in a loop rather than a line and occasionally bunch up rather than flow smoothly, repeating in time the way atoms in ordinary crystals repeat in space.
Now, in a paper published this week, Norman Yao at the University of California, Berkeley, and his colleagues have revealed a blueprint for making a time crystal. The recipe has already been followed by two teams…”
World’s first time crystals cooked up using new recipe – New Scientist