Gluon condensate

In quantum chromodynamics (QCD), the gluon condensate is a non-perturbative property of the QCD vacuum which could be partly responsible for giving masses to light mesons.

If the gluon field tensor is represented as G_μν, then the gluon condensate is the vacuum expectation value ${\displaystyle \langle G_{\mu \nu }G^{\mu \nu }\rangle }$.[1] It is not clear yet whether this condensate is related to any of the known phase changes in quark matter. There have been scattered studies of other types of gluon condensates, involving a different number of gluon fields.

For more on the context in which this quantity occurs, see the article on the QCD vacuum.