Name: Vladyslav Shtabovenko Date: 02/03/17-05:20:03 PM Z
Hi,
Am 01.02.2017 um 15:09 schrieb Pablo Sanchez Puertas:
> Hello again!
>
> Thanks for the long answer and explanations. As I said, don’t
worry
> about the implementation in FeynCalc: I understand that such a
task
> would represent quite some work and I already managed myself to
get
> the numerics for the particular cases I need.
> Moreover, I could check that, as you said, TID[] works
propperly
> whenever non-vanishing Gram determinants appear; in that case the
> option UsePaVeBasis->True does the work perfectly anyway. So I
guess
> that is a nice and general advice.
>
> On the other hand, concerning the current implementation, as I
said,
> there are still some terms which are missing and not included in
the
> references you showed me, but which appear in
> http://dx.doi.org/10.1016/S0550-3213(03)00184-6
> (still, as far as I know, not using DR for IR divergences). You
could,
> for instance, compare numerically with the result obtained from
TID[]
> and evaluating it numerically with LoopTools. In that sense, I
thought
> that would be worthy in the new version that OneLoop[] does
not either
> produce any output for the tensor integrals or produce some
warning.
This should be now fixed, i.e. tensor 5-point functions are not
reduced
to boxes anymore. The formula is applied only to pure scalars
integrals.
Also OneLoop by itself will be considerably reworked for the next
release…
>
> At the moment, I could not come up with an easy and systematic
mehtod
> to do the reduction of tensor integrals and I have not used DR for
IR
> divergences, so I cannot help with the implementation. Anyhow, if
in
> the future I can come up with some method, I will let you know.
>
> Thanks a lot and congrats for the support,
> Pablo
>
Cheers,
Vladyslav