All Questions
4
questions
1
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429
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What exactly does it mean by gauge-invariant "operators"?
For simplicity, let us consider $U(1)$ gauge theory without matter fields.
At classical level, the gauge field $A^\mu$ has the gauge transformation law
\begin{equation}
A^\mu \to A^\mu +\partial^\mu \...
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1
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0
answers
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How does the electromagnetic dipole operator appear in the decay $b \rightarrow s \gamma$?
I was analyzing the effective theory of the process $b \rightarrow s \gamma$ and and I was in doubt about the emergence of the effective operator of photon dipole
$$O_7 = e m_b \bar{s}_L \sigma_{\mu\...
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3
votes
2
answers
483
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Is electric field operator in Schrödinger picture time-dependent?
We know that in the Schrödinger picture, operators are time-independent if they do not have explicit time-dependence.
So do electric field and vector potential field operators have time dependence in ...
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2
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0
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144
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What this quantum field operator represents $ b_{in}(t) = \frac{1}{\sqrt{2 \pi}} \int e^{-i \omega t} b(\omega)$? [duplicate]
In
Input and output in damped quantum systems: Quantum stochastic differential equations and the master equation Physics Department, Uniuersity of Waikato, Hamilton, ¹tuZealand (Received 29 ...
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