Title: Critical Slowing Down in a Real Physical System

Abstract: The behavior of a dynamical system can exhibit abrupt changes when it crosses a tipping point. To prevent catastrophic events, it is useful to analyze indicators of the incoming bifurcation, as the divergence of the relaxation time of the system when approaching the critical point. However, this phenomenon, called critical slowing down (CSD), is hardly measurable in real physical systems. In this paper we provide experimental evidence of CSD in a laser system crossing the emission threshold and we analyze how it is affected by a time changing parameter and by noise.