All Questions
Tagged with coherent-states path-integral
16
questions
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0
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76
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Majorana Boson Coherent States
Consider $a$ be a bosonic operator, and we define $\Phi = a+a^{\dagger}$ and it is clear that $\Phi^{\dagger}=\Phi$ that implies "Majorana Boson". Now, i want to find the coherent states for ...
- 177
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votes
1
answer
222
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Advantage of coherent path integral
I think(?) I am quite familiar with path integral over phase space, but not familiar with the coherent state path integral. What is the advantage of this coherent path integral besides the usual path ...
- 3,622
9
votes
1
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663
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Calculating free energy from coherent state path integral
Edit: It turns out that problem encountered in this question is not limited to BdG Hamiltonians.
I am having trouble in using the coherent state path integral approach to calculate the free energy. ...
- 660
0
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1
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75
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Fermionic coherent state in Fock representation
The notes I follow define a Fermionic coherent state $|c\rangle$ as
\begin{equation}
\hat{c}|c\rangle=c|c\rangle
\end{equation}
where $\hat{c}$ is the Fermionic annihilation operator and $c$ is a ...
- 155
2
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1
answer
100
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Correspondence between terms in generic path integrals
In field theory, starting with a quantum Hamiltonian with field operator $c$, no matter its nature, one obtains the path integral formulation with partition function $$Z=\int DcDc^* \exp{ -S^1_E[c,c^*...
- 115
2
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Coherent state path integral for Dirac fermions
I’m trying to derive the fermionic path integral for the Dirac theory using the coherent state path integral, but I’m not able to get around the presence of a $\gamma_0$ making it look different from ...
- 968
1
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83
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Questions of fermionic coherent states (page 166 of Atland and Simons)
This is quite a basic question but I just can not find the solution.
The question is how do you show equation (2) below. Let me explain the details.
From page 166 of condensed matter book by Atland ...
- 311
3
votes
2
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284
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Coherent States Path Integral of Harmonic Oscillators
I am studying the notes provided by Ben Simons in this link (http://www.tcm.phy.cam.ac.uk/~bds10/tp3.html). I am currently on Lecture 16 (Applications and Connections). The corresponding textbook is ...
user261609
1
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0
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35
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Is there symmetric form for statistical action?
In quantum statistical theory, for a given Hamiltonian $H$, one can express the partition function as
\begin{equation}
Z = \text{tr}\, e^{-\beta H}
\end{equation}
into the coherent path integral ...
- 11
0
votes
1
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98
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Functional representation of operators in second quantization
In path integral formalism, the operator $\hat{a}$ and $\hat{a}^\dagger$ represented by numbers $\alpha$ and $\bar{\alpha}$ according to $\hat{a}$|$\alpha$⟩=$\alpha$|$\alpha$⟩ and <$\alpha$|$\hat{a}...
- 57
3
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Harmonic oscillator in QFT
Given a single bosonic mode with frequency $\omega_0$, such that $\hat{H}=\hbar\omega_0(\frac{1}{2}+\hat{a}^{\dagger}\hat{a})$ how should one show the equivalence between the coherent state path ...
- 892
3
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254
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Boundary conditions of fermionic coherent states path integral
Given the algebra of a fermionic oscillator
$$ \{\hat{a},\hat{a}^\dagger \}=1\,, \qquad \hat{a}^2=(\hat{a}^\dagger)^2=0, $$
with coherent states $ \hat{a}|\xi\rangle=\xi|\xi\rangle $, let's ...
- 187
4
votes
2
answers
595
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Coherent state basis of (relativistic) particle Fock space
For a neutral scalar bosonic particle of mass $m$, I consider a Fock space with an orthonormal basis of momenta eigenstates
\begin{equation}\label{Fock-p-states}
\left|p_1p_2\cdots p_n\right\rangle=\...
- 133
2
votes
1
answer
557
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What is the definition of functions of Grassmann numbers?
I understand there are some relevant questions, but none of them solves my issue.
From Atland and Simons (Condensed Matter Field Theory), the definition of functions of Grassmann numbers are defined ...
- 1,431
11
votes
2
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Why use coherent state path integral? What is its motivation or goal?
In almost all textbooks of quantum field theory for high energy, they insert the position and momentum eigenstate to formulate the path integral. While in condensed matter field theory, they insert ...
- 5,971