A core question we want to understand is where did matter come from. And then, if you know about antimatter, it's natural to ask, why is that not here? The process is not understood and we are hunting for clues as to why it happened, says Dr Christian Smorra, a physicist on the Baryon Antibaryon Symmetry Experiment (Base) at Cern.
For more than two millennia, mathematicians have produced a growing heap of pi equations in their ongoing search for methods to calculate pi faster and faster. The pile of equations has now grown into the thousands, and algorithms now can generate an infinitude. Each discovery has arrived alone, as a fragment, with no obvious connection to the others. But now, for the first time, centuries of pi formulas have been shown to be part of a unified, formerly hidden structure.
A drawn circle is at least something physical. You can see it, touch it, erase it. The skeptic can still say, "Circles are grounded in physical reality. Justice is different; it's just an idea in your head." So let's talk about the number two. Point to it. Not two apples, not two fingers, not a numeral on a page-that's just a symbol.
In terms of making things happen, energy is an indispensable consideration. Systems spontaneously tend towards the lowest-energy state. When a system reaches equilibrium, no further energy can be extracted. That maximum entropy, lowest energy state is the inevitable end-state of the Universe. But until that moment arrives, reactions of all kinds will occur, continuing to liberate energy. In our bodies, chemical bonds break and reform: releasing energy.
Star-formation will eventually end, and then the last shining stars will burn out. Galaxies will dissociate due to gravitational interactions, ejecting all masses and leaving only supermassive black holes behind. And then those black holes will decay via Hawking radiation, leaving only cold, stable, isolated bodies, from which no further energy can be extracted, all accelerating away from us within our dark energy-dominated Universe.
According to Einstein's General Relativity, for every black hole that exists within the Universe, there are only three properties that go into it that matter in any way: the black hole's total mass, the black hole's net electric charge, and the black hole's intrinsic angular momentum, and that's it. It doesn't matter what type of matter went into the black hole in order to form it; all that matters is its mass, charge, and angular momentum.
Analogue quantum simulations are a useful tool for investigating these systems, particularly in regimes in which the applicability of numerical techniques is limited. For different simulator platforms, figures of merit include the electron bandwidth and interaction strength, temperature and the number of simulated lattice sites. Their use is further underscored by the ability to realize distinct lattice geometries, on-site degrees of freedom and by the physical observables that are accessible to experimental measurement.
Hefei National Research Center for Physical Sciences at the Microscale and School of Physical Sciences, University of Science and Technology of China, Hefei, Anhui, China Wen-Zhao Liu, Ya-Bin Zhou, Jiu-Peng Chen, Ao Teng, Xiao-Wen Han, Guang-Cheng Liu, Zhi-Jiong Zhang, Yi Yang, Feng-Guang Liu, Chao-Hui Xue, Bo-Wen Yang, Jin Yang, Chao Zeng, Yi-Zheng Zhen, Feihu Xu, Ye Wang, Yong Wan, Qiang Zhang & Jian-Wei Pan
I don't know who invented this crazy challenge, but the idea is to put someone in a carved-out ice bowl and see if they can get out. Check it out! The bowl is shaped like the inside of a sphere, so the higher up the sides you go, the steeper it gets. If you think an icy sidewalk is slippery, try going uphill on an icy sidewalk. What do you do when faced with a problem like this? You build a physics model, of course.
A grand aspiration of cavity quantum materials research is to uncover fundamentally new routes for controlling properties of matter by judiciously tailoring the quantum electromagnetic environment. Experiments with dark cavities revealed modified transport properties in the integer and fractional quantum Hall states of a 2D electron gas, as well as cavity-assisted thermal control of the metal-to-insulator transition in charge-density-wave systems.