Program for Traces of Dirac matrices

PJK
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Hi all,

I want to calculate traces of Dirac matrices with a program like Mathematica.
I found the package FeynCalc but it seems to be outdated.
It is always producing results like this:
Code:
4 (-(DiracCanonical->False) (Factoring->False) (FeynCalcInternal->True) g^(mu nu) 

(InsideDiracTrace->True) k\[CenterDot]l-l^2 (DiracCanonical->False) (Factoring->False) 

(FeynCalcInternal->True) g^(mu nu) (InsideDiracTrace->True)+m^2 

(DiracCanonical->False) (Factoring->False) (FeynCalcInternal->True) g^(mu nu) 

(InsideDiracTrace->True)+k^nu l^mu (DiracCanonical->False) (Factoring->False) 

(FeynCalcInternal->True) (InsideDiracTrace->True)+k^mu l^nu (DiracCanonical->False) 

(Factoring->False) (FeynCalcInternal->True) (InsideDiracTrace->True)+2 l^mu l^nu 

(DiracCanonical->False) (Factoring->False) (FeynCalcInternal->True) 

(InsideDiracTrace->True))
Which is quite annoying. Even worse I want to use the metric (-1,1,1,1) and there seems to be no support for changing the metric.
Is there a better program/package for doing those calculations?
 
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Apparently this was a difficult question. But maybe one year later someone has got an idea?
I have the same problem as the one described above.
 
I am not too(edit: At all) familiar with the Dirac matrices but following the discussion on

http://mathworld.wolfram.com/DiracMatrices.html

What is wrong with using $Tr(A\otimes B) = Tr(A)Tr(B)$?
 
comote said:
I am not too(edit: At all) familiar with the Dirac matrices but following the discussion on

http://mathworld.wolfram.com/DiracMatrices.html

What is wrong with using $Tr(A\otimes B) = Tr(A)Tr(B)$?

Thanks for your input. Of course it would be possible to implement all the Dirac algebra using the functions of Mathematica. That's what the people of FeynCalc did. But since it has already been done, I would rather use it, instead of redoing it myself. And FeynCalc DOES work; its output is just unreadable (as can be seen in the example above).
 
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The lesser Green's function is defined as: $$G^{<}(t,t')=i\langle C_{\nu}^{\dagger}(t')C_{\nu}(t)\rangle=i\bra{n}C_{\nu}^{\dagger}(t')C_{\nu}(t)\ket{n}$$ where ##\ket{n}## is the many particle ground state. $$G^{<}(t,t')=i\bra{n}e^{iHt'}C_{\nu}^{\dagger}(0)e^{-iHt'}e^{iHt}C_{\nu}(0)e^{-iHt}\ket{n}$$ First consider the case t <t' Define, $$\ket{\alpha}=e^{-iH(t'-t)}C_{\nu}(0)e^{-iHt}\ket{n}$$ $$\ket{\beta}=C_{\nu}(0)e^{-iHt'}\ket{n}$$ $$G^{<}(t,t')=i\bra{\beta}\ket{\alpha}$$ ##\ket{\alpha}##...
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