feynlag.dirac.minkowski_metric

feynlag.dirac.minkowski_metric(idx1, idx2, convention='+---')

Minkowski metric component g^{idx1 idx2}.

Concrete integer indices (0..3) give ±1/0; symbolic indices give a KroneckerDelta expression assuming 4D spacetime with index 0 time-like.

>>> minkowski_metric(0, 0), minkowski_metric(1, 1), minkowski_metric(0, 1)
(1, -1, 0)