All Questions
Tagged with cpt-symmetry quantum-electrodynamics
6
questions
2
votes
1
answer
113
views
CPT invariance and Soft Theorems
I am reading the paper IR Dynamics and Entanglement Entropy, written by Toumbas and Tomaras and I have a question on using the CPT invariance of the QED $S$-matrix elements in order to derive the ...
- 3,992
0
votes
0
answers
44
views
Negative energy quanta vs antimatter approach
Consider 2 physical scenarios:
$t_{-1}$
$t_0$
$t_1$
Sc.1
electron and positron approached
electron and positron annihilated
photons emitted
Sc.2
electron is free
electron emits some photons
...
- 199
0
votes
1
answer
45
views
Can one-electron world theory be revived if the Sakharov's conditions are completely met?
Regarding that people object about the matter antimatter balance in the one-electron world theory to discard it, can it be once more revived if the Sakharov's conditions are met so that the matter ...
- 1,268
2
votes
0
answers
92
views
Does the presence of magnetic monopole break the time reversal, or does its magnetic charge flip (more naturally)?
It is often said that the presence of magnetic field breaks the time reversal symmetry (see Sakurai quantum mechanics book p.285), because the Lorentz force law shows
$$
\vec F = q(\vec E + \vec v \...
- 4,336
2
votes
0
answers
187
views
QED $PC$ conservation
I'm trying to prove that the QED Lagrangian
$$\mathscr{L}=\bar{\psi}(i\!\!\not{\!\partial}-m)\psi - \frac{1}{4}F^{\mu\nu}F_{\mu\nu} - J^\mu A_\mu$$
Is invariant under P and C. The two fields transform ...
- 23
5
votes
2
answers
434
views
Is it possible to have renormalisable C-, P-, or T-violating terms in QED?
In a recent paper (1710.01791), Witten claims that there are no renormalisable $\mathrm C,\mathrm P,\mathrm T$-violating terms that can be included in the QED Lagrangian:
What does this picture say ...
