All Questions
Tagged with scaling renormalization
6 questions with no upvoted or accepted answers
8
votes
0
answers
279
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Fisher exponent and fractal structure
In the context of critical phenomena, there are several critical exponents commonly used to characterize the singular behaviour at the point of phase transition. The Fisher exponent $\eta$ is defined ...
- 518
5
votes
0
answers
116
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Analytic change of free energy after renormalization
Suppose we have some model in statistical physics with Hamiltonian $H$ and partition function
$$Z=\mathrm{Tr}\left(e^{-H}\right) $$
the free energy per site is defined as
$$ f =\frac1N\log Z$$
A ...
- 4,776
4
votes
0
answers
49
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Why/When would one study Renormalization Group flow of a system?
It is not that I am looking for a cheap way out of reading a book about RG flow, but I would like to know few key insights that RG flow study provides, backed with some specific examples. I know a ...
- 343
3
votes
0
answers
137
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Scaling limit, renormalization group and low-energy effective field theories
Given a quantum lattice theory $T_0$, e.g., in one dimension defined on $L$ sites, I know that there is a scaling limit, which introduces a lattice scale $a_0$ and keeps the following two quantities ...
- 823
2
votes
0
answers
50
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What is the meaning of a non-canonical fixed point in the RG flow?
Consider, as an example, the Gaussian model:
$$
S[\phi]=\int\mathrm{d}\vec x\left[\frac{\gamma}{2}\left(\nabla\phi\right)^2+\frac{\mu^2}{2}\phi^2\right].
$$
RG analysis can be performed exactly by ...
- 83
1
vote
0
answers
58
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Using the RG equations to find the free energy scaling form of the 2D Ising Model
i am trying to calculate the scaling form of the free energy of the 2D Ising model, starting from it's RG equations:
$$\frac{d u_I}{dl} = 2 u_I + u_t^2$$
$$\frac{d u_t}{dl} = u_t$$
$$\frac{d u_h}{dl} =...
- 43