Questions tagged [gauge-theory]
A gauge theory has internal degrees of freedom that do not affect the foretold physical outcomes of the theory. The theory has a Lie group of *continuous symmetries* of these internal degrees of freedom, *i.e.* the predicted physics under any transformation in this group on the degrees of freedom. Examples include the $U(1)$-symmetric quantum electrodynamics and other Yang-Mills theories wherein non-Abelian groups replace the $U(1)$ gauge group of QED.
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Cosmic Strings as Topological Defects (heuristics)
I have a lot of troubles to understand heuristically the principle behind Kibble's model for genesis of cosmic strings via Kibble mechanism. More precisely I not understand how to interpret following ...
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Non-abelian Berry connection : clashing time-ordering conventions, and component-wise form
Let $\mathcal{M}$ be a $k$-dimensional parameter space associated to a quantum system with an $N$-dimensional ground state. As usual, we assume the system is subject to some adiabatic tuning of ...
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How is related the exponential map, the covariant derivative and the gauge transformations under Lie groups
I will try to formulate my question the best way possible considering my lack of mathematical formalism.
I just want to know, in every aspects, why spinors transforms (under Lorentz transformations) ...
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Large gauge transformation in $\mathrm{U}(1)$ flux threading argument
In Oshikawa's flux threading argument for the $\mathrm{U}(1)\times T$ Lieb-Schultz-Mattis (LSM) theorem, the author defined a so-called large gauge transformation
$$U=\exp\left(i\frac{2\pi}{L}\sum_{\...
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What means charge-$N$ scalar field $\varphi$?
Let $G = \oplus_{i=1}^N (\mathbb{Z}/N_i)$ be an Abelian group, for sake of simplicity eg a cyclic group $\mathbb{Z}/N$ . We consider abstract $G$- gauge theories.
What is in this context the precise ...
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How is the geometry of the magnetic vector potential determined in the original Aharonov-Bohm experiment?
I've tried but I can't find anything about the geometry of the gauge field, which is mentioned in an article in Scientific American 1981, by Bernstein and Phillips.
They say, without explaining it, ...
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Reasoning about spin coupling on curved space
In the course of QFT i learnt that the gauge field emerges from the need of a gauge invariance in the action, as we use the covariant derivative in minimal coupling. Now i'm studying how spin fields ...
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Charged excitations and Vortices in abstract Abelian Lattice Gauge theory
I have a question about heuristical interpretation of certain used terminology in the setting of abstract Abelian gauge theories as used in this paper by Chenjie Wang, Michael Levin.
On page 4, Part A ...
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Getting rid of the theta term in the standard electroweak theory
This has already been asked here more than once, but the existing answers do not tackle my misunderstanding.
A topological $\theta$-term is understood to be physical, in the usual particle model ...
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