Condensed Matter Seminars

Abstract: In this blackboard talk, I will discuss new results in the field of directed polymers (these are topological objects found in many condensed matter systems, e.g. flux lines in superconductors, domain walls in ferromagnets, and atomic steps on vicinal surfaces). After a detailed introduction, I will describe the physics of "self-localization" of directed polymers, a state induced by elastic interactions between the polymer and its environment. In the latter part of the talk, I will show how the model of self-localization may be mapped to population dynamics, in which, along with local birth and death rules, one imposes a global constraint which fixes the total population. The dynamics of populations under such oppressive control turns out to be very rich, with phases such as "spreading", "collapse", and a novel "pseudo-traveling wave".