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<p style="font:14px/1.5 'Lucida Grande';margin:0;">Hi all,</p>
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<p style="font:14px/1.5 'Lucida Grande';margin:0;">I wonder is there a way or method to simplify the expression with a sy_anti tensor contracted with a lorent_g to 0?</p>
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<p style="font:14px/1.5 'Lucida Grande';margin: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</p>
<p style="font:14px/1.5 'Lucida Grande';margin:0;">0 due to the sy_anti, but I wonder, is there a way or a method to simplify those expression directly to 0?</p>
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<p style="font:14px/1.5 'Lucida Grande';margin:0;">Thanks very much!</p>
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using namespace GiNaC;</p>
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using namespace std;</p>
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int main(int argc, char** argv) {</p>
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symbol a("a"), b("b"), c("c"), d("d"), A("A");</p>
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symbol D("D");</p>
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varidx ia(a,D), ib(b,D), ic(c,D), id(d,D);</p>
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auto ret = indexed(A, sy_anti(0,1,2,3), ia,ib,ic,id) * lorentz_g(ic.toggle_variance(), id.toggle_variance());</p>
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cout << simplify_indexed(ret) << endl;</p>
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return 0;</p>
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}</p>
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Best regards!</p>
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Feng</p>
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