Quantum-ElectroDynamics (QED) is the quantum field theory believed to describe the electromagnetic interaction (and with some extension the weak nuclear force).
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Why did Feynman's thesis almost work?
A bit of background helps frame this question. The question itself is in the last sentence.
For his PhD thesis, Richard Feynman and his thesis adviser John Archibald Wheeler devised an astonishingly ...
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How are classical optics phenomena explained in QED (Snell's law)?
How is the following classical optics phenomenon explained in quantum electrodynamics?
Reflection and Refraction
Are they simply due to photons being absorbed and re-emitted? How do we get to ...
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Spontaneous breaking of Lorentz invariance in gauge theories
I was browsing through the hep-th arXiv and came across this article:
Spontaneous Lorentz Violation in Gauge Theories. A. P. Balachandran, S. Vaidya. arXiv:1302.3406 [hep-th]. (Submitted on 14 ...
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how is shown that photon speed is constant using QED?
In Feynman's simple QED book he talks about the probability amplitude P(A to B) ,where A and B are events in spacetime, and he says that it depends of the spacetime interval but he didn't put the ...
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Simple (but wrong) argument for the generality of positive beta-functions
In the introduction (page 5) of Supersymmetry and String Theory: Beyond the Standard Model by Michael Dine (Amazon, Google), he says
(Traditionally it was known that)
the interactions of ...
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What tree-level Feynman diagrams are added to QED if magnetic monopoles exist?
Are the added diagrams the same as for the $e-\gamma$ interaction, but with "$e$" replaced by "monopole"? If so, is the force between two magnetic monopoles described by the same virtual ...
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QM and Renormalization (layman)
I was reading Michio Kaku's Beyond Einstein. In it, I think, he explains that when physicsts treat a particle as a geometric point they end up with infinity when calculating the strength of the ...
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Can the path of a charged particle under the influence of a magnetic field be considered piecewise linear?
Ordinarily we consider the path of a charged particle under the influence of a magnetic field to be curved. However, in order for the trajectory of the particle to change, it must emit a photon. ...
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how does dynamic casimir effect generate correlated photons
There is a recent paper on arxiv receiving lot of acclaim http://arxiv.org/abs/1105.4714
The authors experimentally show that moving a mirror of a cavity at high speeds produces light from high ...
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Using photons to explain electrostatic force
I am trying to understand the idea of a force carrier with the following example.
Let's say there are two charges $A$ and $B$ that are a fixed distance from each other. What is causing the force on ...
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The Schwinger model
The Schwinger model is the 2d QED with massless fermions. An important result about it (which I would like to understand) is that this is a gauge invariant theory which contains a free massive vector ...
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Why muonium is unstable?
This question is closely related to my previous question Bound states in QED.
Muonium is a system of electron and anti-muon. This article in wikipedia claims that muonium is unstable.
QUESTION: Why ...
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Quantizing EM field
Why when we quantize EM field, whe quantize the vector potential $A^\mu$ obtaining vectorial particles (photons) like the elastic field (phonons) and we can't quantize directly the EM-field tensor ...
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Why isn't light scattered through transparency?
I'm asking a question that has bothered me for years and years. First of all, let me give some context. I'm a layman in physics (college educated, math major). I've read Feynman's QED cover to cover, ...
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Relativistic corrections to quantum mechanics of Coloumb potential
Systems of charged particles (such as atomic nuclei and electrons) can be described by nonrelativistic quantum mechanics with the Coloumb interaction potential. A fully relativistic description is ...
