Questions tagged [adiabatic]
Thermodynamic processes that occur without exchanging heat between the system and its environment.
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If the ground states of interacting QFTs are so complicated, how did Nature find them?
My question was inspired by trying to understand the paper Quantum Algorithms for Quantum Field Theories, by Jordan, Lee, and Preskill. The main result of that paper is that scattering experiments in ...
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The notion of an adiabatic process in thermodynamics -vs- quantum mechanics
I'm confused about the terminology in the two contexts since I can't figure out if they have a similar motivation. Afaik, the definitions state that quantum processes should be very slow to be called ...
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How slow is a reversible adiabatic expansion of an ideal gas?
A truly reversible thermodynamic process needs to be infinitesimally displaced from equilibrium at all times and therefore takes infinite time to complete. However, if I execute the process slowly, I ...
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Why are sound waves adiabatic?
I want to know why we can treat sound waves as an adiabatic process. Precisely, I know that pressure and density vibrations occur so fast that molecules have no time to exchange energy (I might be ...
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Principle of Caratheodory and The Second Law of Thermodynamics
Background
Constantin Carathéodory formulated thermodynamics on a purely mathematical axiomatic foundation. His statement of the second law is known as the Principle of Carathéodory, which may be ...
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Formula for molar specific heat capacity in polytropic process
I found this formula for a polytropic process, defined by $PV^n = {\rm constant}$, in a book:
$$C = \frac R{\gamma-1} + \frac R{1-n} $$
where $C$ is molar specific heat and $\gamma$ is adiabatic ...
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How is this process not quasi-static yet reversible?
Consider a (adiabatic) canister with a piston containing some gas kept in a vacuum. There are two weights on the canister which equalize the pressure of the gas on the piston. Assume the system is at ...
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Adiabatic theorem and Berry phase
As far as I can check, the adiabatic theorem in quantum mechanics can be proven exactly when there is no crossing between (pseudo-)time-evolved energy levels. To be a little bit more explicit, one ...
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Adiabatic piston: why is Callen's argument flawed?
This question is related to this one. I would ask you to read that question and my answer to the question itself before answering this one.
The problem is the following. In his book Thermodynamics, ...
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When is the adiabatic approximation for solid state systems valid?
The adiabatic approximation for solid state systems is rather radical. I was wondering in which cases it breaks down.
As it is based on the idea of the nuclii being much heavier than the electrons I ...
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Basic Thermodynamics: Quasistatic Adiabatic Process
I'm going through the exercises in a Thermodynamics book, just to revise and build my intuition. Right now, I'm working on:
Show that for a quasistatic adiabatic process in a perfect gas, with
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Entropy change in the free expansion of a gas
Consider the adiabatic free expansion of a gas since there is no external Pressure hence Work done on the system is 0 and since the walls are insulated (hence adiabatic) the heat absorbed is 0. ...
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How is ideal gas law applicable to real gas?
I read one of the questions here on physics.stack exchange proving how the speed of sound increases with temperature using ideal gas law equation and adiabatic index. Here's the link:
How can the ...
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Is there a generalization of the adiabatic theorem into a degenerate Hamiltonian?
Adiabatic theorem states that if the Hamiltonian of the system $H(t)$ is slowly changed, and if the initial state is in the $n$th eigenstate of $H(0)$, then the final state will remain in the $n$th ...
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Why is adiabatic process isentropic?
I have read that adiabatic process is isentropic because there is no heat exchange in an adiabatic process and thus no change in entropy.
But my question is - Even in adiabatic process, work can be ...
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