His work covers a wide variety of problems in equilibrium and non-equilibrium statistical mechanics and involves a mixture of rigorous and non-rigorous methods. The main themes in the work are:
- Phase transitions in equilibrium and non-equilibrium systems
- Application of statisical mechanics and mathematical modeling to complex systems in biology, ecology, etc.
- Derivation of hydrodynamical equations from microscopic kinetics
- Phase segregation dynamics
- Statistical mechanics of plasmas
- Time evolution of micro- and macro-quantum systems