Retrieving "Physical Vacuum" from the archives

Cross-reference notes under review

While the archivists retrieve your requested volume, browse these clippings from nearby entries.

1. Chiral Symmetry Restoration

   Linked via "physical vacuum"

   Theoretical Framework in QCD
   In the context of Quantum Chromodynamics (QCD)), chiral symmetry ($SU(Nf)L \times SU(Nf)R$) exists only in the limit of zero quark masses. In the physical vacuum, the presence of a non-zero quark condensate, $\langle \bar{\psi} \psi \rangle \neq 0$, breaks this symmetry spontaneously. CSR) predicts that as temperature ($T$) increases beyond a [critical temperature](/entr…