Title: "Free energy of two-species systems with applications to colloids"

Speaker: Dimitrios Tsagkarogiannis (Università degli Studi dell'Aquila)

Abstract: In this talk we consider a system of small and large spheres in a continuous medium all interacting via positive potentials. This could describe colloidal particles (large spheres) within a substrate (small spheres). Alternatively, it could provide an idealized picture of what may happen in a phase transition when the new phase is getting formed (large spheres) but we still have small isolated particles (small spheres). One interesting phenomenon that occurs is that despite the repulsive forces between all particles, when we look at the effective system of only big spheres there is an attractive force between them usually referred to as "depletion attraction". The question we address in this talk is how to compute the free energy of the system, in particular for the renormalized one, i.e., when we first integrate over the small spheres. We will discuss a sufficient condition for the convergence of the related cluster expansion, which involves the surface of the large spheres rather than their volume (as it would have been the case in a direct application of existing methods to the binary system). This is based on joint works with Sabine Jansen (LMU) as well as with Giuseppe Scola (SISSA) and Xuan Nguyen (NYU-Shanghai).

April 29, from 3:30 p.m. to 4:30 p.m. (Rio de Janeiro local time)

Local: This meeting will take place on Google Meet, through the link below:

https://meet.google.com/haf-zcxs-ckx

More complete information about the seminars can be found HERE.

Sincerely,
Organizers: Giulio Iacobelli e Maria Eulalia Vares