July 18, 2024
A key assumption in the standard thermodynamic description of macroscopic systems is that the system’s interaction with its environment is very weak and can be neglected. For microscopic systems, however, this assumption breaks down. In this talk I will illustrate the impact of strong coupling between a quantum system and its environment in two instances: i) The modification of a harmonic oscillator's thermal energy when strongly coupled to an environment [1], and ii) the combination of thermal uncertainty with quantum uncertainty in a general energy-temperature thermodynamic uncertainty relation [2]. The energy-temperature uncertainty relation is valid for classical and quantum systems at all coupling strengths. But in the quantum regime, strong coupling can lead to non-commutativity effects that create coherences even in equilibrium, which increase temperature uncertainty as well as modify a system's heat capacity. The strong coupling corrections are described by the average Wigner-Yanase-Dyson skew information, a quantity connected to measures of coherence.