42 research outputs found
A numerical test of the Y-system in the small size limit of the SU(2)x SU(2) Principal Chiral Model
Recently, Kazakov, Gromov and Vieira applied the discrete Hirota dynamics to
study the finite size spectra of integrable two dimensional quantum field
theories. The method has been tested from large values of the size L down to
moderate values using the SU(2) x SU(2) principal chiral model as a theoretical
laboratory. We continue the numerical analysis of the proposed non-linear
integral equations showing that the deep ultraviolet region L -> 0 is
numerically accessible. To this aim, we introduce a relaxed iterative algorithm
for the numerical computation of the low-lying part of the spectrum in the U(1)
sector. We discuss in details the systematic errors involved in the
computation. When a comparison is possible, full agreement is found with
previous TBA computations.Comment: 28 pages, 24 figure