> Dear Prffesior,
> I am a research-fellow at a physics institute of India,
> working on "Finite Temperature Field Theory",and "QGP phenomenology".
> I am trying to use Feyncalc for my calculations but facing some problems.
> Let me explain them.
> At finite temperature the propagators and the vertices
> loses the simple Lorentz invariant structure and acquires an admixture
> of both spatial and temporal components. Therefore, to perform these
> calculations the programe should be able to recognige both the zeroth
> and spatial components of a four-vector and know should be able to do
> calculations with DiracGamma and Diracgamma[i],i=1,2,3 explicitly.
> Can such things be done with feynCalc? Plese let me know.
More than 16 years after the original question, the answer is yes, with FeynCalc 9.3 (aka the current development version) this will be possible.
For example (TGA is gamma^0, CGA[i] is gamma^i)
Tr[CGA[i].CGA[j]] (i.e. the trace of two Dirac matrices with Cartesian indices)
-4 CartesianPair[CartesianIndex[i], CartesianIndex[j]]
where CartesianPair[CartesianIndex[i], CartesianIndex[j]] signifies a Kronecker delta
yields 1, since gamma^0 gamma^0 =1, while
DiracSimplify[CGA[i, j, i, j]] (i.e. g^i g^j g^i g^j
This still needs some testing, performance improvements and a proper documentation,
but this is a work in progress to be completed soon.
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