Seminars

google mmet link:meet.google.com/jwk-aitc-aqw Self-driven particle systems are widespread around us. Example ranges from the vehicular traffic on highways to the transport at the molecular scale by motor proteins. One common feature of these type of systems is that the driving forces acting on each particle or agent are not external in origin, but are produced by the constituents themselves. The self-driven character of the individual agent and the complex interactions among them drive these types of systems out-of-equilibrium and emerge different new phenomena. Among a plethora of phenomena observed in self-driven particle systems, one is “overtaking”. In spite of wide spread appearance in nature, there is no comprehensive study and theoretical understanding of this phenomena in the literature. In this talk I will mainly focus on this phenomena. In the first part of my talk, I will discuss the statistics of overtaking events in a system of non-interacting self-driven agents followed by an interacting model of self-driven agents. As quantities of interest, I discuss the conditional and unconditional probability distributions of the net overtaking number by a tagged agent. In the second part of my talk, I will focus on how the finite system-size affects the statistics overtake events by considering the same two systems of non-interacting and interacting self-driven agents. I also discuss the finite-size scaling analysis and the dynamical exponent associated with the fluctuation of the net overtaking number by a tagged agent.

Webinar: join at https://zoom.us/j/98144583184?pwd=SU81bkNUSGJNaUhwOEs4NndiZDhRQT09 We will give a gentle introduction to extensive form games with imperfect recall, and describe some new complexity results. Using a one-to-one correspondence between these games on one side and multivariate polynomials on the other side, we show that in general, solving games with imperfect recall is as hard as solving certain problems of the first order theory of reals. We establish square-root-sum hardness for a specific class called A-loss games. On the positive side, we find restrictions on games and strategies motivated by Bridge bidding that give polynomial-time complexity. Joint work with Hugo Gimbert and Soumyajit Paul.