Philip Thaxton Gressman (born November 22, 1978) is an American mathematician at The University of Pennsylvania, working primarily in the field of harmonic analysis.
[3] Gressman completed his Ph.D. in mathematics at Princeton University in 2005 under the guidance of Elias Stein.
[5] Together with Robert M. Strain, Gressman solved the full Boltzmann equation, which mathematically models the behavior of a dilute gas.
More specifically, they proved global existence of classical solutions and rapid time decay to equilibrium for the Boltzmann equation with long-range interactions, for initial data close to equilibrium.
[6][7] His work on the Boltzmann equation helped him be selected to represent the American Mathematical Society at the 19th Annual Coalition for National Science Funding (CNSF) Capitol Hill Exhibition in May 2013, where he discussed the importance of national science funding for pure and applied mathematics.