Cosmic physics mimicked on table-top as graphene enables Schwinger effect.
Category: particle physics – Page 316
Researchers from the University of Illinois developed GPU-accelerated software to simulate a cell that metabolizes and grows like a living cell.
Every living cell contains its own bustling microcosm, with thousands of components responsible for energy production, protein building, gene transcription and more.
Scientists at the University of Illinois at Urbana-Champaign have built a 3D simulation that replicates these physical and chemical characteristics at a particle scale — creating a fully dynamic model that mimics the behavior of a living cell.
Published in the journal Cell, the project simulates a living minimal cell, which contains a pared-down set of genes essential for the cell’s survival, function and replication. The model uses NVIDIA GPUs to simulate 7,000 genetic information processes over a 20-minute span of the cell cycle – making it what the scientists believe is the longest, most complex cell simulation to date.
Dr. Marvin Minsky — A.I. Pioneer & Mind Theorist. Professor of Media Arts and Sciences, MIT, Media Lab http://GF2045.com/speakers.
As soon as we understand how the human brain works, we should be able to make functional copies of our minds out of other materials. Given that everything is made of atoms, if you make a machine, in some sense it is made of the same kinds of materials as brains are made but organized either in very different ways or fundamentally the same ways.
Interestingly, if you are going to copy the organization of a particular human mind maybe you should make a dozen of them. There is no particular limit on how many copies to make and how the future society will treat them.
When will all these great things happen of overcoming death and making people more intelligent and turning ourselves into machines with replaceable parts so that suffering will disappear? Many great science fiction writers have written well about the future of human minds and what will happen if we eliminate death and people can live forever and we keep growing and so forth.
That is not to say that the advantage has been proven yet. The quantum algorithm developed by IBM performed comparably to classical methods on the limited quantum processors that exist today – but those systems are still in their very early stages.
And with only a small number of qubits, today’s quantum computers are not capable of carrying out computations that are useful. They also remain crippled by the fragility of qubits, which are highly sensitive to environmental changes and are still prone to errors.
Rather, IBM and CERN are banking on future improvements in quantum hardware to demonstrate tangibly, and not only theoretically, that quantum algorithms have an advantage.
We’ve been trying for a long time to make a tiny Sun on Earth, one that would sustainably produce energy by nuclear fusion of hydrogen or similar atoms. Come to think of it, I’d like one for my basement.
Fusion requires quite a bit of heat to get going, but once it does, it starts producing its own heat. If you can keep that system contained so it doesn’t expand too much or allow too much heat to escape, further fusion happens. If it reaches a point where self-heating becomes the primary driver of fusion, you have yourself a “burning plasma”.
The actual Sun has a pretty easy time sustaining fusion because of the crushing gravity at its center, but we Earthlings need to be a bit more creative to achieve that here at home (because we don’t have any 4-nonillion pound weights handy). The burning plasma, indeed a tiny star, is one of the key milestones on the path to usable nuclear fusion. Until now, no one had ever made such a thing.
“It is what I would call a dippy process,” Richard Feynman later wrote. “Having to resort to such hocus-pocus has prevented us from proving that the theory of quantum electrodynamics is mathematically self-consistent.”
Justification came decades later from a seemingly unrelated branch of physics. Researchers studying magnetization discovered that renormalization wasn’t about infinities at all. Instead, it spoke to the universe’s separation into kingdoms of independent sizes, a perspective that guides many corners of physics today.
Renormalization, writes David Tong, a theorist at the University of Cambridge, is “arguably the single most important advance in theoretical physics in the past 50 years.”
If a particle has no mass, how can it exist?
Scientists think that, under some circumstances, dark matter could generate powerful enough gravitational waves for equipment like LIGO to detect.
Four physicists share their journeys through academia into industry and offer words of wisdom for those considering making a similar move.
The ultimate goal, still years away, is to generate power the way the sun generates heat, by smooshing hydrogen atoms so close to each other that they combine into helium, which releases torrents of energy.
WATCH: Is alluring but elusive fusion energy possible in our lifetime?
A team of more than 100 scientists published the results of four experiments that achieved what is known as a burning plasma in Wednesday’s journal Nature. With those results, along with preliminary results announced last August from follow-up experiments, scientists say they are on the threshold of an even bigger advance: ignition. That’s when the fuel can continue to “burn” on its own and produce more energy than what’s needed to spark the initial reaction.
Iron that rusts in water theoretically shouldn’t corrode in contact with an “inert” supercritical fluid of carbon dioxide. But it does.
The reason has eluded materials scientists to now, but a team at Rice University has a theory that could contribute to new strategies to protect iron from the environment.
Materials theorist Boris Yakobson and his colleagues at Rice’s George R. Brown School of Engineering found through atom-level simulations that iron itself plays a role in its own corrosion when exposed to supercritical CO2 (sCO2) and trace amounts of water by promoting the formation of reactive species in the fluid that come back to attack it.
According to our current Cosmological models, the Universe began with a Big Bang roughly 13.8 billion years ago. During the earliest periods, the Universe was permeated by an opaque cloud of hot plasma, preventing atoms from forming. About 380,000 years later, the Universe cooled to a temperature of about-270 °C (−454 °F), which converted much of the energy generated by the Big Bang into light. This afterglow is now visible to astronomers as the Cosmic Microwave Background (CMB), first observed during the 1960s.
One peculiar characteristic about the CMB that attracted a lot of attention was the tiny fluctuations in temperature, which could provide information about the early Universe. In particular, there is a rather large spot in the CMB that is cooler than the surrounding afterglow, known as the CMB Cold Spot. After decades of studying the CMB’s temperature fluctuations, a team of scientists recently confirmed the existence of the largest cold spots in the CMB afterglow – the Eridanus Supervoid – might be the explanation for the CMB Cold Spot that astronomers have been looking for!
The research was conducted by the Dark Energy Survey (DES), an international team of researchers made up of 300 scientists from 25 institutions in seven countries. The research team was led by András Kovacs, an astrophysicist with the Instituto de Astrofísica de Canarias (IAC) and the University of Laguna in Tenerife, Spain. The results of their study, titled “The DES view of the Eridanus supervoid and the CMB cold spot,” appeared in the Monthly Notices of the Royal Astronomical Society on December 17th, 2021.