CPT symmetry

<p>Charge, parity, and time reversal symmetry is a fundamental <a href="/facts/Symmetry_in_physics/gJmgsooI">symmetry</a> of <a href="/facts/Physical_law/aVtc4wpk">physical laws</a> under the simultaneous <a href="/facts/Transformation_(mathematics)/Yr2J3o8H">transformations</a> of <a href="/facts/Charge_conjugation/YJ1vjdfD">charge conjugation</a> (C), <a href="/facts/Parity_transformation/emSbJ4hD">parity transformation</a> (P), and <a href="/facts/T-symmetry/Tgf2LJMc">time reversal</a> (T). CPT is the only combination of C, P, and T that is observed to be an exact symmetry of nature at the fundamental level. The CPT theorem says that CPT symmetry holds for all physical phenomena, or more precisely, that any <a href="/facts/Lorentz_invariant/K5AEuGKg">Lorentz invariant</a> local <a href="/facts/Quantum_field_theory/VoewsNJV">quantum field theory</a> with a <a href="/facts/Self-adjoint_operator/VrH1nEAK">Hermitian</a> <a href="/facts/Hamiltonian_(quantum_mechanics)/5XwK2HmD">Hamiltonian</a> must have CPT symmetry. In layman terms, this stipulates that an <a href="/facts/Antimatter/NvpGDLof">antimatter</a>, <a href="/facts/Mirror/wMu4u6BB">mirrored</a>, and <a href="/facts/T-symmetry/Tgf2LJMc">time reversed</a> universe would behave exactly the same as our regular universe.
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CPT symmetry open-in-new

CPT symmetry