All Questions
Tagged with non-locality path-integral
6
questions
4
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0
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109
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Justification for the derivative expansion in the Exact Renormalization Group
In the Exact Renormalization Group formalism, specifically the formalism of Wetterich, one writes down an evolution equation for the effective average action $\Gamma_k[\varphi]$, see f.ex
$$
\...
- 577
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How can quantum nonlocality be understood in the path integral formalism?
I have always had my difficulties (being bored, impatient) with the theoretical considerations around quantum nonlocality, especially Bell's inequalities. What makes it cumbersome for me is that these ...
- 7,514
7
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2
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411
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Is there a deep reason why action comes from a local lagrangian?
In both classical and quantum physics Lagrangians play a very important role. In classical physics, paths that extremize the action $S$ are the solutions of the Euler-Lagrange equations, and the ...
- 1,290
6
votes
1
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Non-local field redefinition and effects on path-integral measure
Consider the partition function
$$
Z[0] = \int \left[\mathcal{D}A_\mu\right]\left[\mathcal{D}\pi\right] e^{-i \int d^4x \left(-\frac{1}{2}(\partial\pi)^2-\frac{1}{4}F_{\mu\nu}F^{\mu\nu}+ \frac{a}{M^2}...
- 2,197
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Why can't Faddeev-Popov ghosts be replaced with bosons?
Faddeev-Popov ghosts are introduced in the quantization of Yang-Mills theory to absorb the Faddeev-Popov determinant into the action,
$$\det \Delta_{\text{FP}} = \int \mathcal{D} \bar{c} \mathcal{D} c ...
- 103k
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If $: V(\phi) :$ is non-local in space, does that mean interacting quantum field theory is non-local?
Free field theories are definitely local in.
In the interaction picture, we can decompose the fields into creation operator modes and annihilation operator modes. The product of operators can be ...
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