Quantum thermodynamics and the emergence of irreversibility

Understanding the origin of irreversibility is a challenging problem in fundamental physics. When a quantum system is not treated in isolation – but interacts with its surrounding environment – its quantum nature rapidly dissipates due to an irreversible physical process called decoherence.

This area of research seeks to understand the link between microscopic and macroscopic irreversibility and provide a unified theoretical framework in which macroscopic dynamics can be understood from the underlying quantum mechanics. In turn, this will shed light on the source of irreversibility, the emergence of the arrow of time, and the quantum-classical transition.

Research aims

We will analyse the impact of different environmental dynamics on macroscopic thermodynamic properties, and assess distinct scenarios to derive irreversible behaviours from classical and quantum microscopic dynamics.

We will derive master equations of open quantum systems with no timescale separation, focusing in particular on extremely reach memory systems, described in terms of fractional dynamics. We will then obtain the corresponding classical limit, and study in detail the emerging thermodynamic properties of these systems, including fluctuation-dissipation relations and the corresponding entropy functions.

We will also compare these scenarios with the thermodynamics of small systems, and identify possible features distinguishing between different dynamics.


    Meet the team


    Jim Al-Khalili profile image

    Professor Jim Al-Khalili

    University of Surrey

    Dorje C Brody profile image

    Professor Dorje Brody

    University of Surrey

    Paul Davies

    Professor Paul Davies

    Arizona State University

    Thomas Guff

    University of Surrey

    Simon Saunders

    Professor Simon Saunders

    University of Oxford

    Cesare Tronci profile image

    Dr Cesare Tronci

    University of Surrey

    Vlatko Vedral

    Professor Vlatko Vedral

    University of Oxford