[GiNaC-list] question about lorentz_g contract with sy_anti tensor

[Feng Feng]

Thanks very for the reply.

and I have tried the suggestion, i.e., using the following expression:

auto ret = indexed(A, sy_anti(0,1,2,3), ia,ib,ic,id) * lorentz_g(ic, id.toggle_variance());

but I got something like: -delta.d~c*A~d~a~b~c, still a non-zero result.


BTW, if c’s variance is not toggled in lorentz_g,

      then these two dummy index c’s variance is not matched, and is that allowed?


Thanks again!
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