In this paper the interaction potential between static charges in suspended
graphene is studied within the quantum Monte Carlo approach. We calculated the
dielectric permittivity of suspended graphene for the set of temperatures and
extrapolated our results to zero temperature. The dielectric permittivity at
zero temperature has the following properties. At zero distance
ϵ=2.24±0.02. Then it rises and at a large distance the dielectric
permittivity reaches the plateau ϵ≃4.20±0.66. The results
obtained in this paper allow to draw a conclusion that full account of
many-body effects in the dielectric permittivity of suspended graphene gives
ϵ very close to the one-loop results. Contrary to the one-loop result,
the two-loop prediction for the dielectric permittivity deviates from our
result. So, one can expect large higher order corrections to the two-loop
prediction for the dielectric permittivity of suspended graphene.Comment: 6 pages, 2 figure