ATTENTION : jour inhabituel / unusual day

Séminaire général commun SPEC-SPhT
The Casimir force is an attraction between parallel conducting plates due to quantum fluctuations of the electromagnetic (EM) field. Thermal fluctuations of correlated fluids (such as critical mixtures or superfluids) are also modified by boundaries, resulting in similar interactions. A nice demonstration is provided by the thinning of a wetting film of helium at and below the superfluid transition. Quantitative understanding of the latter requires inclusion of surface undulations. The EM Casimir force is also modified for corrugated surfaces in non-trivial fashion. We conclude by examining other non-trivial geometries, in particular addressing the question of whether a repulsive force can arise for a piston.

MIT