Questions tagged [cpt-symmetry]
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Why is the Higgs $CP$ even?
Why was it always assumed that the Higgs boson is a CP even particle?
I understand that experimentally, it just is so but I am under the impression that before its discovery people took it to be CP ...
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Antiparticles, CPT and leptogenesis
When people are being careful they'll tell you that antiparticles are the CPT conjugates of particles. You can't say that they are C conjugates or CP because these, while they do reverse the charge, ...
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C and T Symmetry of Free Dirac Lagrangian
I want to show the $C$ and $T$ symmetry of the free Dirac Lagrangian
$$\mathcal{L}=\overline{\psi}\left(i\gamma^\mu\partial_\mu-m\right)\psi.$$
Following the notation of Peskin, Schroeder, we have ...
- 1,187
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Why is it important that the combination of charge, parity & time reversal symmetry not violated?
If looking for more particles or decays that violate CP symmetry can explain why there is so few antimatter in the known universe, I guess finding things that violate CPT symmetry might helps clear up ...
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Is time reversal symmetry true on the microscopic level?
I often hear that on the microscopic level, time-reversal symmetry is true for all physical processes. However, I can easily come up with counterexamples that seem to disprove this:
Two particles of ...
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Does the weak force obey the CPT symmetry? How?
I have read that the weak force does not obey the charge symmetry, the parity symmetry, and the time reversal symmetry.
Then how does it obey the CPT symmetry?
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What are the assumptions that $C$, $P$, and $T$ must satisfy?
I am not asking for a proof of the $CPT$ theorem. I am asking how the $CPT$ theorem can even be defined.
As matrices in $O(1,3)$, $T$ and $P$ are just
$$
T = \begin{pmatrix} -1 & 0 & 0 & ...
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How is a half-odd integer spin field defined in the Wightman axioms?
Can anyone give me a proper definition of 'half-odd integer spin fields' in terms of the Wightman axioms? I'm trying to prove the anti-unitarity of the PCT operator in 'PCT, Spin and Statistics, and ...
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What operator gives the mass of a particle?
Talking about why a particle and its antiparticle have the same mass, my professor said the Hamiltonian commutes with TCP, so mass is conserved. I don't understand that.
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Clarifying PT symmetry
I understand that if a Hamiltonian remains invariant under the following transformations then it is PT invariant,
\begin{eqnarray}
\mathrm{Parity \; reversal:} \; \; \hat{p} \to -\hat{p} \; \; \...
- 131
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Does reversing time give parity reversed antimatter or just antimatter?
Feynman's idea states that matter going backwards in time seems like antimatter.
But, since nature is $CPT$ symmetric, reversing time ($T$) is equivalent to $CP$ operation. So, reversing time gives ...
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What is the definition of the charge conjugation?
I seem to have troubles finding definitions of the charge conjugation operator that are independant of the theory considered.
Weinberg defined it as the operator mapping particle types to ...
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Clarification on CPT symmetry
CPT symmetry, as I understand it, holds that if all charge, parity, and time were reversed (a mirror-image antimatter time-reversed universe), that universe would behave identically to our current ...
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CPT symmetry as it applies to matter/antimatter
I've heard/read a couple different definitions for antimatter: it is charge-reversed matter (typical definition, for the lay person at least), or it's time-reversed matter (as described in QED).
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chiral symmetry condensate and 2SC, CFL breaking C, P and T symmetry?
Because we know that chiral symmetry condensate causes the chiral symmetry breaking, and it produces Goldstone modes of pseudo-scalars, so I believe that chiral symmetry breaking also breaks the T ...
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