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Aug 29, 2022

How does classical, Newtonian inertia emerge from quantum mechanics?

Posted by in categories: information science, quantum physics

From my understanding, inertia is typically taken as an axiom rather than something that can be explained by some deeper phenomenon. However, it’s also my understanding that quantum mechanics must reduce to classical, Newtonian mechanics in the macroscopic limit.

By inertia, I mean the resistance to changes in velocity — the fact of more massive objects (or paticles, let’s say) accelerating more slowly given the same force.

What is the quantum mechanical mechanism that, in its limit, leads to Newtonian inertia? Is there some concept of axiomatic inertia that applies to the quantum mechanical equations and explains Newtonian inertia, even if it remains a fundamental assumption of quantum theory?

Aug 29, 2022

It’s finally here: Lockheed Martin delivers 60+ kW laser to the US Navy

Posted by in category: military

Enhancing overall combat system effectiveness

“Lockheed Martin and the U.S. Navy share a common vision and enthusiasm for developing and providing disruptive laser weapon systems,” said in the statement Rick Cordaro, vice president of Lockheed Martin Advanced Product Solutions.

Aug 29, 2022

Defenseless Against Hypersonic Missiles, US Navy Turns To ‘Faster & Lethal’ DEWs To Battle China, Russia

Posted by in categories: energy, military

The US Navy is exploring the novel technology of Directed Energy Weapons (DEWs) against Chinese and Russian hypersonic weapons in the absence of a potent defense against these highly maneuverable missiles.

The top admiral of the US Navy, Michael Gilday stated that directed energy systems are being developed as a potential countermeasure against hypersonic missiles, calling the advancements made by Russia and China in hypersonic weapon technology “a significant concern.”

The development of devices that would use high-energy lasers or high-power microwaves to remove a threat is a major priority for the Navy, according to Adm. Michael Gilday, Chief of Naval Operations, who is also the Chief of US Missile Defense Agency.

Aug 29, 2022

Space Warfare

Posted by in categories: military, space

This episode focuses on the basic concepts and misconceptions of wars fought in space and examines the notions of weapons, defenses, stealth in space, and the distance involved.

Project Rho: http://www.projectrho.com/public_html/rocket/index.php.
Military Science Fiction: http://www.milsf.com.

Continue reading “Space Warfare” »

Aug 29, 2022

Scientists are unraveling the mystery of the arrow of time

Posted by in categories: biological, neuroscience, particle physics

The flow of time from the past to the future is a central feature of how we experience the world. But precisely how this phenomenon, known as the arrow of time, arises from the microscopic interactions among particles and cells is a mystery—one that researchers at the CUNY Graduate Center Initiative for the Theoretical Sciences (ITS) are helping to unravel with the publication of a new paper in the journal Physical Review Letters. The findings could have important implications in a variety of disciplines, including physics, neuroscience, and biology.

Fundamentally, the of arises from the second law of thermodynamics: the principle that microscopic arrangements of physical systems tend to increase in randomness, moving from order to disorder. The more disordered a system becomes, the more difficult it is for it to find its way back to an ordered state, and the stronger the arrow of time. In short, the universe’s tendency toward disorder is the fundamental reason why we experience time flowing in one direction.

“The two questions our team had were, if we looked at a particular system, would we be able to quantify the strength of its arrow of time, and would we be able to sort out how it emerges from the micro scale, where cells and interact, to the whole system?” said Christopher Lynn, the paper’s first author and a postdoctoral fellow with the ITS program. “Our findings provide the first step toward understanding how the arrow of time that we experience in emerges from these more microscopic details.”

Aug 29, 2022

Reversing cause and effect is no trouble for quantum computers

Posted by in categories: computing, quantum physics

Watch a movie backwards and you’ll likely get confused—but a quantum computer wouldn’t. That’s the conclusion of researcher Mile Gu at the Centre for Quantum Technologies (CQT) at the National University of Singapore and Nanyang Technological University and collaborators.

In research published 18 July in Physical Review X, the international team shows that a computer is less in thrall to the arrow of time than a classical computer. In some cases, it’s as if the quantum computer doesn’t need to distinguish between cause and effect at all.

The new work is inspired by an influential discovery made almost 10 years ago by complexity scientists James Crutchfield and John Mahoney at the University of California, Davis. They showed that many statistical data sequences will have a built-in arrow of time. An observer who sees the data played from beginning to end, like the frames of a movie, can model what comes next using only a modest amount of memory about what occurred before. An observer who tries to model the system in reverse has a much harder task—potentially needing to track orders of magnitude more information.

Aug 29, 2022

Geely’s Zeekr will deliver EVs with 600+ mile range, CATL battery tech in Q1 2023

Posted by in category: energy

The CATL tech with impressive claims for energy density, cooling, and range will first go into the Chinese premium EV brand.

Aug 29, 2022

Civilian AI Is Already Being Misused by the Bad Guys

Posted by in category: robotics/AI

And the AI community needs to do something about it.

Aug 28, 2022

Startup’s Hydrogen Breakthrough May Give New Life to Coal Plants

Posted by in categories: energy, innovation

Australian lab uses catalyst to generate 700ºC heat from hydrogen that could be used to retrofit power stations.

Aug 28, 2022

Scientists Discover “Superworms” Capable of Munching Through Plastic Waste

Posted by in categories: chemistry, economics

According to the American Chemistry Council, in 2018 in the United States, 27.0 million tons of plastic ended up in landfills compared to just 3.1 million tons that were recycled. Worldwide the numbers are similarly bad, with just 9% of plastic being recycled according to a recent Organization for Economic Co-operation and Development (OECD) report.

The statistics are even worse for certain types of plastic. For example, out of 80,000 tons of styrofoam (polystyrene.

Polystyrene was discovered by accident in 1,839 by Eduard Simon, an apothecary from Berlin, Germany. As one of the most widely used plastics in the world, polystyrene is used for bottles, containers, packaging, disposable cutlery, packing peanuts, and more. It can be solid or foamed (Styrofoam is a brand name of closed-cell extruded polystyrene foam).