Lifeboat Foundation

I explore the reduction of thermodynamics to statistical mechanics by treating the former as a control theory: a theory of which transitions between states can be induced on a system (assumed to obey some known underlying dynamics) by means of operations from a fixed list. I recover the results of standard thermodynamics in this framework on the assumption that the available operations do not include measurements which affect subsequent choices of operations. I then relax this assumption and use the framework to consider the vexed questions of Maxwell’s demon and Landauer’s principle. Throughout I assume rather than prove the basic irreversibility features of statistical mechanics, taking care to distinguish them from the conceptually distinct assumptions of thermodynamics proper.

Annual UWO Philosophy of Physics Conference.
Thermodynamics as a Resource Theory: Foundational and Philosophical Implications.
June 20–22, 2018
http://philphysics.uwo.ca.
David Wallace, University of Southern California.

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Dark energy is the name physicists have given to the mysterious thing driving the universe’s accelerated expansion. It may be a force or a form of energy, and one piece of evidence suggests it is hidden inside black holes.

Sir Roger Penrose, a mathematician and physicist from the University of Oxford who recently shared this year’s Nobel Prize in physics, says that our universe has undergone numerous Big Bangs, with another one on the way.

The acoustically generated force will help astronomers better understand the sun’s photosphere and the causes of space weather.

Two neutron stars collided which caused a huge explosion but with an unusually flawless form, baffling scientists. Usually, a collision between neutron stars would lead to a flattened cloud but the recently observed explosion formed a perfectly spherical shape, SpaceAcademy.org reports.

It is still unclear how this is possible, but a new study may shed light on the fundamental physics involved and help scientists calculate the universe’s age. Astrophysicists from the Universe of Copenhagen discovered the kilonova and described it in full in their study, titled “Spherical Symmetry in the Kilonova At2017gfo/GW170817,” which was published in the journal Nature.

The Planck Temperature – Absolute Hot: What is the hottest temperature possible.

Today I’m going to look at the Planck Temperature and it’s about to get very strange. Let’s find out more.

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Gas clouds in the Cygnus X Region, a region where stars form, are composed of a dense core of molecular hydrogen (H₂) and an atomic shell. These ensembles of clouds interact with each other dynamically in order to quickly form new stars. That is the result of observations conducted by an international team led by scientists at the University of Cologne’s Institute of Astrophysics and at the University of Maryland.

Until now, it was unclear how this process precisely unfolds. The Cygnus X region is a vast luminous cloud of gas and dust approximately 5,000 light years from Earth. Using observations of spectral lines of ionized carbon (CII), the scientists showed that the clouds have formed there over several million years, which is a fast process by astronomical standards. The results of the study, “Ionized carbon as a tracer for the assembly of interstellar clouds,” will appear in the next issue of Nature Astronomy.

The observations were carried out in an international project led by Dr. Nicola Schneider at the University of Cologne and Prof Alexander Tielens at the University of Maryland as part of the FEEDBACK program on board the flying observatory SOFIA (Stratospheric Observatory for Infrared Astronomy). The new findings modify previous perceptions that this specific process of star formation is quasi-static and quite slow. The dynamic formation process now observed would also explain the formation of particularly massive stars.

The game-changing neutron star merger of August 2017 created a ‘perfect’ explosion, according to a new study.

The blast behind the historic gravitational wave astronomy discovery of August 2017 had a perfect spherical shape, according to a new study.

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Say you have a cutting-edge gadget that can crack any safe in the world—but you haven’t got a clue how it works. What do you do? You could take a much older safe-cracking tool—a trusty crowbar, perhaps. You could use that lever to pry open your gadget, peek at its innards, and try to reverse-engineer it. As it happens, that’s what scientists have just done with mathematics.

Researchers have examined a deep neural network—one type of artificial intelligence, a type that’s notoriously enigmatic on the inside—with a well-worn type of mathematical analysis that physicists and engineers have used for decades. The researchers published their results in the journal PNAS Nexus on January 23. Their results hint their AI is doing many of the same calculations that humans have long done themselves.

The paper’s authors typically use deep neural networks to predict extreme weather events or for other climate applications. While better local forecasts can help people schedule their park dates, predicting the wind and the clouds can also help renewable energy operators plan what to put into the grid in the coming hours.