Archive for the ‘quantum physics’ category: Page 656
Mar 21, 2019
Quantum Scarring Appears to Defy Universe’s Push for Disorder
Posted by Genevieve Klien in categories: particle physics, quantum physics
One of the first quantum simulators has produced a puzzling phenomenon: a row of atoms that repeatedly pops back into place. Physicists have been racing to explain what might be going on.
Mar 20, 2019
The best topological conductor yet: Spiraling crystal is the key to exotic discovery
Posted by Quinn Sena in categories: computing, quantum physics
The realization of so-called topological materials—which exhibit exotic, defect-resistant properties and are expected to have applications in electronics, optics, quantum computing, and other fields—has opened up a new realm in materials discovery.
Several of the hotly studied topological materials to date are known as topological insulators. Their surfaces are expected to conduct electricity with very little resistance, somewhat akin to superconductors but without the need for incredibly chilly temperatures, while their interiors—the so-called “bulk” of the material—do not conduct current.
Now, a team of researchers working at the Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab) has discovered the strongest topological conductor yet, in the form of thin crystal samples that have a spiral-staircase structure. The team’s study of crystals, dubbed topological chiral crystals, is reported in the March 20 edition of the journal Nature.
Mar 20, 2019
We did a breakthrough ‘speed test’ in quantum tunnelling, and here’s why that’s exciting
Posted by Quinn Sena in categories: particle physics, quantum physics
Things get weird at the quantum level and now we know they can happen really fast when a particle pushes through an almost insurmountable barrier.
Mar 20, 2019
For The First Time, Physicists Have Clocked The Ghostly Speed of Quantum Tunnelling
Posted by Genevieve Klien in categories: particle physics, quantum physics
In quantum physics, particles can ’tunnel’ through seemingly impenetrable barriers, even when they apparently don’t have the energy to do so. Now, researchers have gleaned behind the curtain to better understand how this trick is done.
This problem has puzzled scientists for decades – in particular, the time it takes for particles to do their quantum tunnelling, and get from one side of a barrier to another.
In the case of the atomic hydrogen particles used in these experiments, the researchers found that it happens instantaneously.
Mar 19, 2019
Karen Uhlenbeck Is First Woman to Win Abel Prize for Mathematics
Posted by Genevieve Klien in categories: mathematics, particle physics, quantum physics
For the first time, one of the top prizes in mathematics has been given to a woman.
On Tuesday, the Norwegian Academy of Science and Letters announced it has awarded this year’s Abel Prize — an award modeled on the Nobel Prizes — to Karen Uhlenbeck, an emeritus professor at the University of Texas at Austin. The award cites “the fundamental impact of her work on analysis, geometry and mathematical physics.”
One of Dr. Uhlenbeck’s advances in essence described the complex shapes of soap films not in a bubble bath but in abstract, high-dimensional curved spaces. In later work, she helped put a rigorous mathematical underpinning to techniques widely used by physicists in quantum field theory to describe fundamental interactions between particles and forces.
Continue reading “Karen Uhlenbeck Is First Woman to Win Abel Prize for Mathematics” »
Mar 18, 2019
Physicists reverse time using quantum computer
Posted by Quinn Sena in categories: computing, law, quantum physics, space travel
Researchers from the Moscow Institute of Physics and Technology teamed up with colleagues from the U.S. and Switzerland and returned the state of a quantum computer a fraction of a second into the past. They also calculated the probability that an electron in empty interstellar space will spontaneously travel back into its recent past. The study is published in Scientific Reports.
“This is one in a series of papers on the possibility of violating the second law of thermodynamics. That law is closely related to the notion of the arrow of time that posits the one-way direction of time from the past to the future,” said the study’s lead author Gordey Lesovik, who heads the Laboratory of the Physics of Quantum Information Technology at MIPT.
“We began by describing a so-called local perpetual motion machine of the second kind. Then, in December, we published a paper that discusses the violation of the second law via a device called a Maxwell’s demon,” Lesovik said. “The most recent paper approaches the same problem from a third angle: We have artificially created a state that evolves in a direction opposite to that of the thermodynamic arrow of time.”
Mar 15, 2019
This Is Why The Multiverse Must Exist
Posted by Genevieve Klien in categories: cosmology, quantum physics
If you accept cosmic inflation and quantum physics, there’s no way out. The Multiverse is real.
Mar 14, 2019
Scientists Have “Reversed Time” Inside A Quantum Computer, And The Implications Are Huge
Posted by Quinn Sena in categories: computing, quantum physics
Time: it’s constantly running out and we never have enough of it. Some say it’s an illusion, some say it flies like an arrow. Well, this arrow of time is a big headache in physics. Why does time have a particular direction? And can such a direction be reversed?
A new study, published in Scientific Reports, is providing an important point of discussion on the subject. An international team of researchers has constructed a time-reversal program on a quantum computer, in an experiment that has huge implications for our understanding of quantum computing. Their approach also revealed something rather important: the time-reversal operation is so complex that it is extremely improbable, maybe impossible, for it to happen spontaneously in nature.
As far as laws of physics go, in many cases, there’s nothing to stop us going forward and backward in time. In certain quantum systems it is possible to create a time-reversal operation. Here, the team crafted a thought experiment based on a realistic scenario.
Mar 13, 2019
IBM made a quantum algorithm that could make AI more powerful
Posted by Genevieve Klien in categories: information science, quantum physics, robotics/AI
Artificial intelligence can automatically sort out data, but it struggles for some particularly complex datasets – a quantum algorithm could do better.