Name: Sharaz Date: 03/27/05-03:48:33 PM Z


Ive stumbled upon a weird problem when using the mathematicas replace function in an expression with gamma matrices.

If one has the follwing expression - mathematica figures out how to replace:

-—————————–

In[23]:= GS[l]FeynAmpDenominator[{l}{l+q}];

In[24]:= %/.GS[l]FeynAmpDenominator[{l}{l+q}]->GS[J]

Out[24]:= GS[J]

-—————————–

Which works perfectly. But as soon as you insert another slashed momentum f.exp. GS[q] enters, replace stops working:

-—————————–

In[23]:= GS[l].GS[q]FeynAmpDenominator[{l}{l+q}];

In[24]:= %/.GS[l]FeynAmpDenominator[{l}{l+q}]->GS[J]

Out[24]:= GS[l].GS[q]FeynAmpDenominator[{l}{l+q}]

-—————————–

It just returns the expression, it shuld rather return

GS[J].GS[q]

Is it a bug? - if not how on earth can one substitute something else in?

Thank you

Sharaz