2000 character limit reached
Minimax Isometry Method: A compressive sensing approach for Matsubara summation in many-body perturbation theory (1909.01740v3)
Published 4 Sep 2019 in cond-mat.mtrl-sci, cond-mat.str-el, cs.NA, math.FA, and math.NA
Abstract: We present a compressive sensing approach for the long standing problem of Matsubara summation in many-body perturbation theory. By constructing low-dimensional, almost isometric subspaces of the Hilbert space we obtain optimum imaginary time and frequency grids that allow for extreme data compression of fermionic and bosonic functions in a broad temperature regime. The method is applied to the random phase and self-consistent $GW$ approximation of the grand potential. Integration and transformation errors are investigated for Si and SrVO$_3$.