Seminar Event Detail

Financial/Actuarial Mathematics

 Date:  Wednesday, January 19, 2022 Location:  Zoom Virtual (4:00 PM to 5:00 PM) Title:  McKean-Vlasov equations involving hitting times: blow-ups and global solvability Abstract:   We study two McKean-Vlasov equations involving hitting times. Let $(B(t); \, t \ge 0)$ be standard Brownian motion, and $\tau:= \inf\{t \ge 0: X(t) \le 0\}$ be the hitting time to zero of a given process $X$. The first equation is $X(t) = X(0) + B(t) - \alpha \mathbb{P}(\tau \le t)$. We provide a simple condition on $\alpha$ and the distribution of $X(0)$ such that the corresponding Fokker-Planck equation has no blow-up, and thus the McKean-Vlasov dynamics is well-defined for all time $t \ge 0$. We take the PDE approach and develop a new comparison principle. The second equation is $X(t) = X(0) + \beta t + B(t) + \alpha \log \mathbb{P}(\tau \le t)$, $t \ge 0$, whose Fokker-Planck equation is non-local. We prove that if $\beta,1/\alpha > 0$ are sufficiently large, the McKean-Vlasov dynamics is well-defined for all time $t \ge 0$. The argument is based on a relative entropy analysis. This is joint work with Erhan Bayraktar, Gaoyue Guo and Wenpin Tang. Files: Speaker:  Paul Zhang Institution:  UCSD Event Organizer:

Edit this event (login required).