The symmetry-breaking tag has no wiki summary.
7
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Why do we need Higgs field to re-explain mass, but not charge?
We already had definition of mass based on gravitational interactions since before Higgs. It's similar to charge which is defined based on electromagnetic interactions of particles.
Why did Higgs ...
4
votes
4answers
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How does Higgs Boson get the rest mass?
Higgs Boson detected at LHC is massive. It has high relativistic mass means it has non-zero rest mass.
Higgs Boson gives other things rest mass. But, how does it get rest mass by itself?
17
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10answers
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What is spontaneous symmetry breaking in QUANTUM systems?
Most descriptions of spontaneous symmetry breaking, even for spontaneous symmetry breaking in quantum systems, actually only give a classical picture.
According to the classical picture, spontaneous ...
11
votes
1answer
433 views
Emergent symmetries
As we know, spontaneous symmetry breaking(SSB) is a very important concept in physics. Loosely speaking, zero temprature SSB says that the Hamiltonian of a quantum system has some symmetry, but the ...
5
votes
0answers
143 views
Breaking of Lorentz invariance
Thinking about the concept of symmetry breaking led me to the following question:
Let's say that I have a theory described by a Lorentz invariant Lagrangian, and the true vacuum of the theory is not ...
9
votes
2answers
861 views
Norton's dome and its equation
Norton's dome is the curve $$h(r) = -\frac{2}{3g} r ^{3/2}.$$ Where $h$ is the height and $r$ is radial arc distance along the dome. The top of the dome is at $h = 0$.
Via Norton's web.
If we put ...
2
votes
1answer
444 views
Chiral anomaly and decay of the pion
I am told that if all classical symmetries were reflected as quantum symmetries, the decay of the neutral pion $$\pi^0 ~\longrightarrow~ \gamma\gamma$$ would not happen. Why would the conservation of ...
9
votes
3answers
414 views
Spontaneous breaking of Lorentz invariance
Is it possible to spontaneously break Lorentz invariance, i.e., have a Lagrangian that respects LI but a vacuum which does not? If it is possible, why isn't there even the slightest hint of the ...
4
votes
1answer
94 views
Spontaneous symmetry breaking: How can the vacuum be infinitly degenerate?
In classical field theories, it is with no difficulty to imagine a system to have a continuum of ground states, but how can this be in the quantum case?
Suppose a continuous symmetry with charge $Q$ ...
3
votes
2answers
305 views
What is the role of the vacuum expectation value in symmetry breaking and the generation of mass?
Consider a theory of one complex scalar field with the following Lagrangian.
$$
\mathcal{L}=\partial _\mu \phi ^*\partial ^\mu \phi +\mu ^2\phi ^*\phi -\frac{\lambda}{2}(\phi ^*\phi )^2.
$$
The ...
