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Do you have any recommendation for a book? I studied classical thermodynamics (and physics) long ago and I consider I have good probability and statistics found

by plafl 5y ago

Do you have any recommendation for a book? I studied classical thermodynamics (and physics) long ago and I consider I have good probability and statistics foundations but never studied statistical mechanics. From my ignorance I cannot understand how is it possible that entropy considerations (macroscopic) are applicable to a microscopic demon.

andi999 5y ago
The idea is that temperature alway gives you an energy distribution p(E) =exp(-E/kT)*const. https://de.m.wikipedia.org/wiki/Boltzmann-Statistik https://de.m.wikipedia.org/wiki/Boltzmann-Statistik if you want to store information with one particle in a double well potential (tiny ist information storage), you need the barrier at least so high that you don't just hop to the next bin due to these fluctuation. This means you have to introduce a minimum energy effort depending on temperature needed to delete the information later. Ps statistical physics is slightly weird, not sure about a good book. Maybe Berkeley physics course vol 5 or so. About the Landauer principle itself I remember the paper actually to be quite accessible.
BlueTemplar 5y ago
I'm not aware of a good book, but here's a website that has finally made me understand postmodern thermodynamics : (Though I perhaps have a non-common path of learning modern thermodynamics, then skipping basic physical statistics, only to jump into advanced physical statistics later ?) http://www.av8n.com/physics/thermo/entropy.html http://www.av8n.com/physics/thermo/entropy.html Some core ideas : - 19th century modern thermodynamics are hopelessly obsolete (at least if you want to understand the "why" and/or do stuff more advanced than "basic" heat engines ?) with tons of confused notions like "heat". - The term "thermodynamics" itself is bad, "energo-informatics" would perhaps be a better one ? - Entropy is just a redundant term for (the lack of) information about a system (= macrostate = distribution). - Hence, you need at least some quantum mechanics : Heisenberg's unsharpness principle (and Plank's constant h) to be able to build the theory from the microstate up, because you need to be able to quantize position and momentum to define information. - disorder is another of those misleading terms

by plafl 5y ago

andi999 5y ago

The idea is that temperature alway gives you an energy distribution p(E) =exp(-E/kT)*const. https://de.m.wikipedia.org/wiki/Boltzmann-Statistik https://de.m.wikipedia.org/wiki/Boltzmann-Statistik if you want to store information with one particle in a double well potential (tiny ist information storage), you need the barrier at least so high that you don't just hop to the next bin due to these fluctuation. This means you have to introduce a minimum energy effort depending on temperature needed to delete the information later. Ps statistical physics is slightly weird, not sure about a good book. Maybe Berkeley physics course vol 5 or so. About the Landauer principle itself I remember the paper actually to be quite accessible.

BlueTemplar 5y ago

I'm not aware of a good book, but here's a website that has finally made me understand postmodern thermodynamics : (Though I perhaps have a non-common path of learning modern thermodynamics, then skipping basic physical statistics, only to jump into advanced physical statistics later ?) http://www.av8n.com/physics/thermo/entropy.html http://www.av8n.com/physics/thermo/entropy.html Some core ideas : - 19th century modern thermodynamics are hopelessly obsolete (at least if you want to understand the "why" and/or do stuff more advanced than "basic" heat engines ?) with tons of confused notions like "heat". - The term "thermodynamics" itself is bad, "energo-informatics" would perhaps be a better one ? - Entropy is just a redundant term for (the lack of) information about a system (= macrostate = distribution). - Hence, you need at least some quantum mechanics : Heisenberg's unsharpness principle (and Plank's constant h) to be able to build the theory from the microstate up, because you need to be able to quantize position and momentum to define information. - disorder is another of those misleading terms