Expectation values in the Lieb-Liniger bose gas

Taking advantage of an exact mapping between a relativistic integrable model and the Lieb–Liniger model we present a novel method to compute expectation values in the Lieb–Liniger Bose gas both at zero and finite temperature. These quantities, relevant in the physics of one-dimensional ultracold Bose gases, are expressed by a series that has a remarkable behavior of convergence. Among other results, we show the computation of the three-body expectation value at finite temperature, a quantity that rules the recombination rate of the Bose gas.