SciPost Physics Submission Conformal field theory on top of a breathing one-dimensional gas of hard core bosons P. Ruggiero1*, Y. Brun2, J. Dubail2 1 International School for Advanced Studies (SISSA) and INFN, Via Bonomea 265, 34136 Trieste, Italy 2 Laboratoire de Physique et Chimie Th´eoriques, CNRS, Universit´ede Lorraine, F-54506 Vandoeuvre-les-Nancy, France *
[email protected] April 29, 2019 Abstract The recent results of [J. Dubail, J.-M. St´ephan,J. Viti, P. Calabrese, Scipost Phys. 2, 002 (2017)], which aim at providing access to large scale correlation functions of inhomogeneous critical one-dimensional quantum systems |e.g. a gas of hard core bosons in a trapping potential| are extended to a dynami- cal situation: a breathing gas in a time-dependent harmonic trap. Hard core bosons in a time-dependent harmonic potential are well known to be exactly solvable, and can thus be used as a benchmark for the approach. An extensive discussion of the approach and of its relation with classical and quantum hydro- dynamics in one dimension is given, and new formulas for correlation functions, not easily obtainable by other methods, are derived. In particular, a remark- able formula for the large scale asymptotics of the bosonic n-particle function y y 0 0 0 0 Ψ (x1; t1) ::: Ψ (xn; tn)Ψ(x1; t1) ::: Ψ(xn; tn) is obtained. Numerical checks of the approach are carried out for the fermionic two-point function |easier to access numerically in the microscopic model than the bosonic one| with perfect agree- ment. Contents 1 Introduction 2 1.1 Context