Inconsistency in the calculation of the time-displaced Green's function
According to the documentation (sec. 8.4.5, page 86, tex source here), the routine Predefined_Obs_tau_Green_measure
measures
<c^dag(i,tau,s)c(j,0,s)>
The actual code in Predefined_Obs_mod.F90
here contains
Z = cmplx(0.d0,0.d0,Kind(0.d0))
Do nf = 1, N_FL
Z = Z + GT0(I1,J1,nf)
enddo
But GT0
(Documentation, page 69) is actually
GT0(i,j,s) = <c(i,tau,s)c^dag(j,0,s)>
Notice however that the equal-time routine computes the <c^dag(i,s)c(j,s)>
, consistent with the documentation.
So, we have two options:
- We fix the routine
Predefined_Obs_tau_Green_measure
, substituting hereGT0(I1, J1, nf)
with-G0T(J1, I1, nf)
. This will however change the output of the program - We change the documentation. But this would be somehow inconsistent with the equal-time routines.
I would prefer the first solution.
Edited by Francesco Parisen Toldin