Name: Vladyslav Shtabovenko (email_not_shown)
Date: 07/31/15-04:50:08 PM Z


Hi Nikita,

could you may be provide the results for Line13,14,15 and 16
that you computed by hand?

As far as I can see, each of this line's separately will have an
imaginary part because of the presence of an odd number of gamma^5
in each trace. So by just looking at these expressions I would expect
the result to contain Levi-Civita tensors, although of course there
might be physical reasons why this shouldn't be the case.

Is it also clear that the u^3 terms cannot appear anywhere else? May be
by momentum conservation one can get additional q^2 terms elsewhere?

Cheers,
Vladyslav

Am 31.07.2015 um 03:01 schrieb Nikita Belyaev:
> Hi Vladyslav ,
>
>> sorry for the late reply. I must also apologize because the FORM code
>> that I sent you was not correct.
> That's really bad news because we've already started celebration :(
>
>> Please find the corrected code attached.
>> May be you could also check what happens if you compute just
>> Line13*Line14 or Line15*Line16.
>>
>> Do those results agree with what you computed by hand?
> Totally not. Each term providing a half of FeynCalc's result (5 non-canceling terms with u^3 as before). The same story with other traces which also had been validated to be real by hand.
>
> In the previous email you've also noticed that our traces contain part like (1+GA[5].GS[s]) and (GS[p]+-m). It is correct as far as the first expression has taking into account the polarization of initial particle and the +- sign has related to particle and antiparticle.
>
> Do you have any other ideas about what might be wrong? Because I'm completely lost with that, everything should be correct.
>
> Best Regards,
> Nikita Belyaev
>



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