In this Review paper in p.1462, bottom left: Rev.Mod.Phys.80:1455-1515,2008 -- Color superconductivity in dense quark matter
It says that "There is an associated gauge-invariant 6-quark order parameter with the flavor and color structure of two Lambda baryons,
$$
\langle\Lambda\Lambda\rangle
$$
where
this order parameter distinguishes the color flavor locking (CFL) phase from the quark gluon plsma QGP.
I suppose that it means the 6 quark condensate is
$$
\bigl\langle(\epsilon^{abc}\epsilon_{ijk}\psi^a_i\psi^b_j\psi^c_k)
(\epsilon^{a'b'c'}\epsilon_{i'j'k'}\psi'^a_i\psi'^b_j\psi'^c_k)\bigr\rangle,
$$
but how does this distinguish CFL from QGP?
Is this operator precise? And is this gauge invariant under SU(3)???
It is a Lorentz scalar or pseudo scalar?
It seems that the claim is not clear.
This post imported from StackExchange Physics at 2020-11-05 13:26 (UTC), posted by SE-user annie marie heart