All Questions
Tagged with entanglement-entropy or entropy
3,254 questions
0 votes
0 answers
40 views
Does dissipation have different gravitational entropy effects depending on which mass dissipates in a bound system?
Consider a bound two-body system ($M>>m$) such as Earth–Moon. I'm trying to understand whether there's a meaningful asymmetry in how identical dissipation processes affect gravitational entropy ...
- 111
1 vote
3 answers
139 views
Callen's thermodynamics - is it possible for the state of maximum entropy to lie on unphysical thermodynamic coordinates?
I have a question regarding the second edition of Callen's Thermodynamics and an Introduction to Thermostatistics, which regards his third postulate: Postulate III. [...] The entropy is continuous ...
- 1,253
0 votes
1 answer
107 views
Is $\Delta H$ equal to $\Delta Q_{irreversible}$?
In the proof of spontaneity criterion in constant pressure and temperature, the steps are: $$\Delta S_{system} - \frac{\Delta Q_{rev}}{T}=0 $$ and $$\Delta Q_{rev} > \Delta Q_{irrev}$$ So, we may ...
- 432
2 votes
0 answers
54 views
Affine Transformations of Entropy
In my professors script for Thermodynamics stated that for different systems there can only be one global affine transformation the reasoning is the following: The additivity of the entropy of ...
- 31
0 votes
1 answer
47 views
What is a machine in Callen's Thermodynamics and is it something different to "the basic problem"?
\begin{align} \text{First Law of Thermodynamics (integrated form): } & U = W + Q \\ \Leftrightarrow \\ \text{First Law of Thermodynamics (differential form): } & \underbrace{dU}_{\text{exact ...
- 171
1 vote
1 answer
72 views
What is the connection between "the basic problem of thermodynamics", the entropy formalism and the first law of thermodynamics in Callen?
\begin{align} \text{First Law of Thermodynamics integrated form: } U=W + Q \\ \Leftrightarrow \\ \text{First Law of Thermodynamics differential form: } \underbrace{dU}_\text{exact differential form}= \...
- 171
2 votes
1 answer
108 views
What is an Equilibrium State for Callen?
This question is based on Callen's book "Thermodynamics and An Introduction to Thermostatistics". My understanding is that for gases, liquids and other macroscopic systems, macroscopic ...
- 171
2 votes
2 answers
95 views
How to see entropy vanishes for fermionic gas at $T = 0$ from the grand potential?
I want to see the entropy of a Fermi gas vanish at $T=0$ without using the density matrix as some answers have utilized online. The grand potential for fermi gas (Second Eq. in Sec. 9.4 on page 92) is ...
- 1,726
1 vote
0 answers
66 views
Can entanglement correspond to a state where the thermodynamic arrow of time becomes locally undefined?
While studying quantum entanglement and thermodynamics, I started wondering about a possible conceptual link between the two. In a bipartite pure entangled state we have: Total entropy: S_total ≈ 0 ...
- 11
1 vote
0 answers
61 views
Kolmogorov complexity in physics - applications [duplicate]
Has there been application of Kolmogorov complexity to physics? Shannon entropy has an interpretation from thermodynamics. In principle Kolmogorov complexity and Shannon entropy are the same but is ...
- 11
2 votes
2 answers
244 views
How can we justify the application of (classical!) thermodynamic formalism to parts of the universe that are not isolated?
I have been studying classical thermodynamics for the past few weeks and I have a question that has been bothering me somewhat. To begin, I will pose a short thought experiment to derive a conclusion ...
- 1,253
1 vote
0 answers
121 views
Does the relationship $dQ=TdS$ for quasi-static processes with well-defined work function $dW=-pdV$ hold if there are changes in chemical composition?
The question can be summarized as this: is it valid, for a quasi-static process where the only mode of work is pressure-volume work, to identify $TdS$ with the quasi-static heat flux to the system ...
- 1,253
1 vote
3 answers
583 views
Is this a valid example of a quasi-static process where the relationship $dQ=TdS$ does not hold?
After discussion with @almost_okay under this answer, I feel the need to dedicate a whole thread to the question under discussion since the comment exchange was getting quite long. I realized a ...
- 1,253
-3 votes
2 answers
100 views
Is A/C (Air Conditioner ) consider as reverse entropy? [closed]
Can we consider the air condition as reversing entropy? what are the other process like that?
- 141
2 votes
2 answers
277 views
Why does Callen not take into account the change in entropy of the reversible work source?
I am reading the second edition of Callen's Thermodynamics and in particular about the maximum work theorem which essentially states that a process which produces work and heat produces maximum work ...
- 1,253