Name: jinghantao Date: 12/02/04-03:02:53 AM Z


feyncalc£¬hello
     when i use trace fuction to calculate the expression:Tr[(GA[j].GS[q] - GS[q].GA[j]).(GA[i].GS[q] - GS[q].GA[i])],the result is null. But for the expression:Tr[DiracSimplify[(GA[j].GS[q] - GS[q].GA[j]).(GA[i].GS[q] - GS[q].GA[i])]],the result isnot null, furthermore, the second expression’s result is the same to my manuscript. why? Could you give me some help? thanks very much.
        

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¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡jinghantao
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¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡2004-12-02