The gauge-invariance tag has no wiki summary.
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314 views
Is spacetime an illusion?
In consistent histories, for gauge theories, can the projection operators used in the chains be not gauge invariant?
In quantum gravity, for a projection operator to be gauge invariant means it has ...
3
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0answers
111 views
Wilson lines, boundary conditions, surface defects of TQFTs
I asked the following question in mathematics stack exchange but I'd like to have answers from physicists too;
I have been studying (extended) topological quantum field theories (in short TQFTs) from ...
3
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0answers
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Gauge invariance of gg->gg scattering amplitude?
I'm trying to calculate the spin and color averaged gg->gg cross section, and I am stumbling upon gauge invariance:
Must the amplitude not be invariant under replacements $\epsilon_i \to \epsilon_i + ...
3
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0answers
150 views
Attempts to explain Higgs coupling as a gauge transformation symmetry
As is (supposedly) well known, Electromagnetic coupling can be "explained" as a closure term to a langrangian comprising a free Dirac field and a free vector field that are required to be invariant ...
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What is non-Abelian about non-Abelian Chern-Simons' theory?
One is aware that in the axial gauge (say the light-cone gauge $A_{-}=0$) non-supersymmetric Chern-Simons' theory is a quadratic theory. Hence in this gauge there are no gauge-gauge interactions. Then ...
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Yang-Mills Coulomb Gauge
My Question is how to explicitly move into the "Coulomb gauge" in Yang-Mills theory.
Using the answer provided by QMechanic, one can move into the "temporal gauge" for Yang-Mills fields: Gauge fixing ...
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0answers
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The gauge-invariance of the probability current
It is simple to show that under the gauge transformation $$\begin{cases}\vec A\to\vec A+\nabla\chi\\
\phi\to\phi-\frac{\partial \chi}{\partial t}\\
\psi\to \psi ...
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71 views
How to charge a field?
In a previous post [ Noether theorem, gauge symmetry and conservation of charge ] we were discussing the different ways to demonstrate the current conservation: via the first Noether theorem applied ...
