Linked Questions
14 questions linked to/from What, in simplest terms, is gauge invariance?
182
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Gauge symmetry is not a symmetry?
I have read before in one of Seiberg's articles something like, that gauge symmetry is not a symmetry but a redundancy in our description, by introducing fake degrees of freedom to facilitate ...
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3
answers
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Covariance in gauge theories: why should the Lagrangian be gauge invariant?
I am following a course about gauge theories in QFT and I have some questions about the physical meaning of what we are doing.
This is what I understood:
When we write a Lagrangian $\mathcal{L}(\phi)...
- 1,450
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3
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Can we do path integrals in gauge theories without fixing a gauge?
I am aware that when quantizing gauge theories with a path integral, one needs to add a gauge fixing term to avoid over-counting gauge related field configurations. From an aesthetic perspective, I ...
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11
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2
answers
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What is the physical meaning of Lorenz gauge condition? [closed]
What is the physical meaning of Lorenz gauge condition?
And what part of the solutions we throw?
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1
answer
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What is a gauge theory?
Please note that I just read about 20 forum discussions, none of which answered my question. This question is related to my earlier question Is spacetime symmetry a gauge symmetry?.
I am looking for ...
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4
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1
answer
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Hamiltonian lattice gauge theory with physically observable local degrees of freedom
In my answer at What, in simplest terms, is gauge invariance?, I mentioned that in certain contexts there can be a "gauge theory" with a local symmetry that leave the Lagrangian/Hamiltonian invariant ...
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3
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1
answer
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Lagrangian gauge theory with physically observable local degrees of freedom
In my answer at What, in simplest terms, is gauge invariance?, I mentioned that in certain contexts there can be a "gauge theory" with a local symmetry that leave the
Lagrangian/Hamiltonian invariant ...
- 48.3k
0
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1
answer
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How local gauge invariance explain charge conservation and electromagnetic force appearance?
Without electromagnetic coupling, the QM charged particle wave function is not invariant under a local gauge transformation — one with a phase that depends
on space (space-time):
\begin{equation}
\psi ...
- 2,635
2
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2
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Gauge Invariance in Electrodynamics
I am studying Electrodynamics and I have been introduced to the concept of Gauge Invariance.
This was introduced by noting that $E$ and $B$ amount to 6 six degrees of freedom and the Maxwell ...
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0
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1
answer
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Simplest example of a gauge theory?
I am not a physicist. I’ve read some informal stuff about gauge theory and gauge symmetries, however it’s pretty abstract to me.
Can you give the simplest non-trivial example of a gauge theory? E.g. ...
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3
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0
answers
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Gauge theory and lattice gauge theory [closed]
This is a question is a follow-up to the answer by @tparker about what in simple terms is gauge invariance. I want to know in detail the subtleties of the definitions for gauge theory (#3) and lattice ...
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0
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0
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Is a translation a gauge symmetry?
A gauge symmetry is a symmetry (often local) which doesn't affect the physical quantities or the Lagrangian.
A translation of the whole Universe 3 meters to the left won't affect anything physically.
...
user84158
4
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0
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Physical VS gauge Symmetry
When we work in path integral formalism in some field theory (or even in QM), we usually look on the action, find its symmetries and than treat them as a gauge symmetry - we sum over all possible ...
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Is there a physical mechanism explaining the link between Gauge-Bosons and local Gauge-Invariance?
Imposing local gauge-invariance naturally couples e.g. a charged fermion-field to the electromagnetic field.
To my understanding local gauge-invariance is imposed because a gauge in one system should ...
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