# Jiaqi Liu

I am a Postdoctoral Fellow in Applied Mathematics and Computational Science (AMCS) at the University of Pennsylvania. I am very fortunate to have Robin Pemantle and Xin Sun as my mentors. I obtained my Ph.D. in Mathematics from the University of California, San Diego in 2022. My advisor is Jason Schweinsberg. Prior to UCSD, I received my Bachelor's degree in Mathematics and Applied Mathematics at Beijing Normal University. Here is my CV.

Email: liujiaqi@sas.upenn.edu

Office: DRL 3N4C

### Research interests

### I work in probability theory. I am broadly interested in random models with branching structures that have backgrounds in physics or biology, including branching Brownian motion and coalescence, population models and conformal loop ensembles. Here is my research statement and Google Scholar profile.

### Manuscripts in Preparation

Joint distribution of extremal distances between CLE loops, with Nina Holden and Xin Sun. In preparation

### Papers

The Yaglom limit for branching Brownain motion with absorption and slightly subcritical drift, with Julien Berestycki, Bastien Mallein and Jason Schweinsberg, arXiv:24009.08789, 2024. Paper

Phase transition of the consistent maximal displacement of branching Brownian motion, with Julien Berestycki, Bastien Mallein and Jason Schweinsberg, arXiv: 2406.04526, 2024. Paper

Improved critical drift estimates for the frog model on trees, with Poly Mathews Jr., Electronic Communications in Probability, 2024. Paper (From Polymath Jr. Undergraduate Program)

Critical drift estimates for the frog model on trees, with Emma Bailey and Matthew Junge, Electronic Journal of Probability, 2024. Paper

Particle configurations for branching Brownian motion with an inhomogeneous branching rate, with Jason Schweinsberg, Latin American Journal of Probability and Mathematical Statistics, 2023. Paper

A Yaglom type asymptotic result for subcritical branching Brownian motion with absorption, Stochastic Processes and their Applications, 2021. Paper

### Invited Talks

Sep 2024 AMS Fall Central Sectional Meeting, Special Session on Applications of Probability in Biology

Jul 2024 Two-Dimensional Random Geometry Workshop, IMSI, Slides

Feb 2024 Purdue Probability Seminar

Nov 2023 UChicago Probability and Statistical Physics Seminar

Jul 2023 Hua Loo-Keng Applied Mathematics Forum for Junior Researchers, Chinese Academy of Sciences

Apr 2023 UVA Probaiblity Seminar

Feb 2023 Lehigh Prob/Stat Seminar

Nov 2022 17th Workshop on Markov Processes and Related Topics, Beijing Normal University

Nov 2022 CUNY Probability Seminar, Slides

Oct 2022 Penn/Temple Probability Seminar

April 2022 THU-PKU-BNU joint probability webinar

Feb 2022 AWM Colloquium, University of California San Diego, Slides

Jun 2021 7th Workshop on Branching Markov Processes and Relative Topics, Peking University and Beijing Normal University, Slides

Mar 2021 Probability Seminar, Beijing Normal University, Slides

### Contributed Talks and Posters

May 2024 6th Cincinnati Symposium on Probability, Poster session, Poster session, Poster

May 2022 Centre de recherches mathématiques (CRM) workshop: Branching systems, reaction-diffusion equations and population models, Poster session, Poster

Sep 2021 6th Bath-Beijing-Paris Branching Structures Meeting, Poster session, Slides Video

Jul 2021 Bernoulli-IMS 10th World Congress in Probability and Statistics, Contributed talk, Video

Aug 2020 Bernoulli-IMS One World Symposium, Contributed talk, Video

### Teaching

I am currently the instructor for Math 1400 Calculus at Upenn. From 2017-2022, I taught as a teaching assistant in fifteen courses ranging from pre-calculus to graduate level probability courses at UCSD. Below are the section notes I prepared for some of the classes I TA-ed for.