## Low temperature relaxational dynamics of the Ising chain in a transverse field

Subir Sachdev and A.P. Young

Abstract
We present asymptotically exact results for the real time order parameter correlations of a general class of $d=1$ Ising models in a transverse field at low temperatures ($T$) on both sides of the quantum critical point. The correlations are a product of a $T$-independent factor determined by quantum effects, and a $T$-dependent relaxation function which comes from a {\em classical} theory. We confirm our predictions by a no-free-parameter comparison with numerical studies on the nearest neighbor spin-1/2 model.