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

[Feng Feng]

Hi all,


I wonder is there a way or method to simplify the expression with a sy_anti tensor contracted with a lorent_g to 0?


Please have a look at the following code, I expect ret is 0, and the output looks like “A~b~a.c~c”, it is actually

0 due to the sy_anti, but I wonder, is there a way or a method to simplify those expression directly to 0?


Thanks very much!


using namespace GiNaC;

using namespace std;


int main(int argc, char** argv) {


    symbol a("a"), b("b"), c("c"), d("d"), A("A");

    symbol D("D");

    varidx ia(a,D), ib(b,D), ic(c,D), id(d,D);



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



    cout << simplify_indexed(ret) << endl;



    return 0;

}


Best regards!

Feng
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