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"Everything should be as simple as it is, but not simpler", Albert Einstein
Browsing All Posts filed under »Thermodynamics«
Revisiting Thermodynamic Efficiency
Breaking time-reversal symmetry in a thermoelectric device affects its efficiency in unexpected ways. Thermodynamic engines convert heat into useful work. Testing the optimal efficiency of these machines has been at the forefront of scientific developments ever since 1824, when Sadi Carnot showed that in a simple engine undergoing a reversible thermodynamic cycle, the ratio between […]
The Enigma of Entropy
January 13, 2013
Deepak Dhar One of the most mysterious of laws of nature is the second law of thermodynamics. There are several equivalent formulations of One of the most mysterious of laws of nature is the second law of thermodynamics. There are several equivalent formulations of this law. For our present discussion, it is enough to take […]
Thermodynamics of a Black Hole with Moon
November 13, 2012
Samuel E. Gralla, Alexandre Le Tiec For a rotating black hole perturbed by a particle on the “corotating” circular orbit (angular velocity equal to that of the event horizon), the black hole remains in equilibrium in the sense that the perturbed event horizon is a Killing horizon of the helical Killing field. The associated surface […]
Transforming noise into mechanical energy at nanometric level
November 12, 2012
Driving a Macroscopic Oscillator with the Stochastic Motion of a Hydrogen Molecule Christian Lotze, Martina Corso, Katharina J. Franke, Felix von Oppen, Jose Ignacio Pascual Energy harvesting from noise is a paradigm proposed by the theory of stochastic resonances. We demonstrate that the random switching of a hydrogen (H2) molecule can drive the oscillation of […]
Building the Smallest Possible Ice Crystal
September 21, 2012
It may sound like a Zen koan, but it’s a serious scientific question: How many molecules of water does it take to make the smallest possible ice crystal? Because crystals are defined by a repeated, three-dimensional arrangement of molecules, you can’t necessarily take any small group of bonded-together molecules and call them a crystal. That’s […]
Physicist Derives Laws of Thermodynamics For Life Itself
September 10, 2012
The laws of thermodynamics must apply to self-replicating systems. Now one physicist has worked out how Here’s an interesting thought experiment. Imagine a box filled with a variety of atoms and molecules in proportions roughly equivalent to the composition of the prebiotic soup in which life thrives. How likely is it that these molecules will […]
Entangled Particles Break Classical Law of Thermodynamics
August 1, 2012
Japanese physicists show how to extract more energy from entangled particles than is possible with classical thermodynamics In 1867, the Scottish physicist, James Clerk Maxwell, published a thought experiment showing how to extract heat from a container of gas. Maxwell dreamt up a container divided in half by a wall with a trap door that […]
The Single Theory That Could Explain Emergence
May 7, 2012
Organisation And The Origin of Life Biochemists have long imagined that autocatalytic sets can explain the origin of life. Now a new mathematical approach to these sets has even broader implications One of the most puzzling questions about the origin of life is how the rich chemical landscape that makes life possible came into existence. […]
Optical Device is More Than 100% Efficient
March 8, 2012
LED converts heat into light A light-emitting diode (LED) that emits more light energy than it consumes in electrical energy has been unveiled by researchers in the US. The device – which has a conventional efficiency of greater than 200% – behaves as a kind of optical heat pump that converts lattice vibrations into infrared […]
Physics ‘demon’ reveals fundamental heat of forgetting
March 8, 2012
Read also: Wiping data will cost you energy by Stephen Battersby WE’RE used to the waste heat produced by electrical wires and car brakes. Not so familiar is the heat created by erasing a digital memory. Now an experiment inspired by a metaphorical demon has measured this fundamental heat, which will one day impose a […]
Video: Entropy in the kitchen
February 4, 2012
http://youtu.be/9R1OX4fZqKY Read more: http://www.guardian.co.uk
Thermodynamics – Basic Principles
January 22, 2012
Logical and mathematical aspects of the basic concepts of thermodynamics are considered. G. V. Skornyakov FOREWORD This treatise is in no way meant to serve as a help in gaining acquaintance with the theory of thermal processes. Discussion of the fundamentals of a theory can bear fruit only if led with competent enough people. The […]
Sean Carroll: The Arrow of Time feat
November 14, 2011
MinutePhysics Why is the past different from the future? Caltech physicist Sean Carroll explains how the arrow of time is not an intrinsic property of physics, but rather an emergent feature. http://youtu.be/GdTMuivYF30
New Thermodynamic Paradigm of Chemical Equilibria
October 31, 2011
B. Zilbergleyt The paper presents new thermodynamic paradigm of chemical equilibrium, setting forth comprehensive basics of Discrete Thermodynamics of Chemical Equilibria (DTd). Along with previous results by the author during the last decade, this work contains also some new developments of DTd. Based on the Onsager’s constitutive equations, reformulated by the author thermodynamic affinity and […]
Maxwell’s Demon and Data Compression
October 24, 2011
Akio Hosoya , Koji Maruyama , Yutaka Shikano In an asymmetric Szilard engine model of Maxwell’s demon, we show the equivalence between information theoretical and thermodynamic entropies when the demon erases information optimally. The work gain by the engine can be exactly canceled out by the work necessary to reset demon’s memory after optimal data […]
Supercapacitor electrodes go for a dip
October 22, 2011
A new and simple “dipping” technique that can significantly improve the performance of supercapacitors has been developed by researchers at Stanford University in the US. The method, dubbed “conductive wrapping”, could be applied to a range of electrode materials. It might even be used to improve next-generation electrodes made from sulphur, lithium manganese phosphate and […]
Life in the Universe by Stephen Hawking
August 28, 2011
In this talk, I would like to speculate a little, on the development of life in the universe, and in particular, the development of intelligent life. I shall take this to include the human race, even though much of its behaviour through out history, has been pretty stupid, and not calculated to aid the survival […]
What role does the third law of thermodynamics play in Szilard engines?
August 19, 2011
The role of the third law of thermodynamics in the Szilard engine has been addressed. If the ground state is non-degenerate, the entropy production defined as the work extractable from the engine divided by temperature vanishes as temperature approaches zero due to the third law. The degenerate ground state induced by the symmetry or by […]
Exquisite Machines
July 24, 2011
By Sean Gibbons The synthesis of non-equilibrium thermodynamics and biology, pursued in fits and starts over the years by an eccentric cast of thinkers, has produced a few scientific red herrings, but the overall idea has expanded our biophysical horizons. I’ll summarize what I’ve come to understand about the development of biological thermodynamics and its implications, […]
The thermodynamic meaning of negative entropy
June 6, 2011
Erase entangled memory to cool a computer Imagine cooling a supercomputer not with fans or freezers, but by deleting some of its memory. New calculations show that this is possible, provided some of the bits that make up the computer’s memory are “entangled”– a spooky property that can link two quantum systems, no matter how far […]
February 11, 2013
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