Most of my current mathematical work involves problems in geometric analysis that involve addressing geometric questions by means of studying an associated partial differential equation. The things I spend most of my time thinking about are related to mathematical relativity. I am also interested in applications of (partial) differential equations in a variety of other disciplines, including physics, life-sciences, and economics/finance.

### Summer projects with undergraduates

**Summer 2017**: I worked with students Karlie Schwartzwald and Sara Stout on discrete approximations of boundary value problems.**Summer 2016:**I worked with students Eli Barnes and Mack Beveridge on geometric flows for polygons.**Summer 2014:**Two students did independent research projects under my supervisition: Colin Gavin worked on mean curvature flow; Sam Stewart worked on numerical models of blowup phenomena for nonlinear waves.**Summer 2011:**I worked with Alison Fankhauser and Jenny Louthan creating numerical models for reaction-diffusion equations arising in chemistry. Inspired by conversations during this project, I wrote a short introduction to the Fredholm alternative, based on analyzing finite-difference approximations. These notes, in turn, lead to a paper in the College Mathematics Journal.**Summer 2010:**I worked with Katie Tsukahara and Adam Layne studying the Dirichlet problem for curve shortening flow on spheres.

### Papers

- Paul T. Allen, James Isenberg, John M. Lee and Iva Stavrov Allen. Asymptotic Gluing of Shear-Free Hyperboloidal Initial Data Sets.
*Annales Henri Poincaré*(2021). https://arxiv.org/abs/1912.02839 - Paul T. Allen. Boundary Value Problems and Finite Differences.
*College Math Journal*47 (2016), no. 1, 34 – 41. - Paul T. Allen, James Isenberg, John M. Lee, Iva Stavrov Allen. The shear-free condition and constant-mean-curvature hyperboloidal initial data.
*, , arXiv:1506.06090.* - Paul T. Allen and Iva Stavrov Allen. Smoothly compactifiable shear-free hyperboloidal data is dense in the physical topology. Annales Henri Poincare (2017) 18: 2789. https://doi.org/10.1007/s00023-017-0565-2 (arXiv:1506.05842).
- Paul T. Allen, James Isenberg, John M. Lee, Iva Stavrov Allen. Weakly asymptotically hyperbolic manifolds. arXiv:1506.03399.
Volume 26 (2018), Number 1.*Communications in Analysis and Geometry,* - Paul T. Allen, Adam Layne, Katharine Tsukahara. The Dirichlet problem for curve shortening flow. arXiv:1208.3510
- Allen, Paul T.; Andersson, Lars; Restuccia, Alvaro. Local well-posedness for membranes in the light cone gauge.
*Comm. Math. Phys.*301 (2011), no. 2, 383–410.arXiv, MathSciNet - Allen, Paul T.; Rendall, Alan D. Asymptotics of linearized cosmological perturbations.
*J. Hyperbolic Differ. Equ.*7 (2010), no. 2, 255 – 277.arXiv, MathSciNet - Allen, Paul T.; Clausen, Adam; Isenberg, James Near-constant mean curvature solutions of the Einstein constraint equations with non-negative Yamabe metrics.
*Classical Quantum Gravity*25 (2008), no. 7, 075009, 15 pp.arXiv, MathSciNet - Allen, Paul; Andersson, Lars; Isenberg, James Timelike minimal submanifolds of general co-dimension in Minkowski space time.
*J. Hyperbolic Differ. Equ.*3 (2006), no. 4, 691 – 700.arXiv, MathSciNet

### Some presentations

A very incomplete list of a few (somewhat recent) talks….

- March 2020: local organizer for the Pacific Northwest Geometry Seminar
- October 2019: Geometric Analysis Seminar at University of Oregon
- February 2019: Oregon Liberal Arts Mathematics Colloquium at Linfield College (slides)
- January 2019: Colloquium and Topology-Geometry Seminar at Oregon State University
- January 2018: Talk in AMS Special Session on Mathematical Relativity and Geometric Analysis at JMM (slides)
- October 2017: Talk at Pacific University (sorry, no slides).
- March 2017: Talk at the Charleston AMS meeting (slides)
- February 2017: Short talk to math students at Lewis & Clark (slides)
- July 2016: Talk at BIRS workshop “Geometric Analysis and General Relativity” (slides)
- March 2016: Colloquium at University of Connecticut (slides)
- January 2016: I gave a short talk at the Joint Math Meetings. (slides)
- Summer 2015: Mathematisches Forschungsinstitut Oberwolfach.
- Spring 2015: Lewis & Clark Physics Colloquium (slides).
- Fall 2014: Seattle University Mathematics Colloquium (slides).
- Summer 2014: University of Science & Technology of China, Geometric Analysis and Relativity (sorry, no slides).
- Spring 2014: Willamette University Physics Colloquium (slides)