During the 2024–25 academic year, the CMSA will be hosting a seminar on General Relativity, organized by Uri Kol and Puskar Mondal.

This seminar will take place on Tuesdays from 11:00 am – 12:00 pm (Eastern time). The meetings will take place in Room G10 at the CMSA, 20 Garden Street, Cambridge MA 02138, and some meetings will take place virtually on Zoom or be held in hybrid formats.

To learn how to attend, please fill out this form to join the mailing list.

The schedule will be updated as talks are confirmed.

Formation of Trapped Surfaces in Geodesic Foliation

Virtual

General Relativity Seminar Speaker: Xuantao Chen, Johns Hopkins University Title: Formation of Trapped Surfaces in Geodesic Foliation Abstract: We reprove the formation of trapped surfaces for the Einstein vacuum equation using the incoming geodesic foliation. All previous results, starting with the seminal work of Christodoulou, make use of the double null foliation. In the new […]

pp Waves: Quasinormal Modes & Hidden Symmetries of Black Holes

CMSA Room G10 CMSA, 20 Garden Street, Cambridge, MA, United States

General Relativity Seminar Speaker: Ahmed Seta, Harvard University Title: pp Waves: Quasinormal Modes & Hidden Symmetries of Black Holes Abstract: The spectrum of quasinormal modes of 4D flat space black holes is not analytically tractable, but there are two asymptotic limits where the QNM spectrum is under control: weak damping and strong damping. In this talk, I […]

The Einstein-Euler system with a physical vacuum boundary in spherical symmetry

CMSA Room G10 CMSA, 20 Garden Street, Cambridge, MA, United States

General Relativity Seminar Speaker: Marcelo Disconzi, Vanderbilt University Title: The Einstein-Euler system with a physical vacuum boundary in spherical symmetry Abstract: We establish local well-posedness for the Einstein-Euler system with a physical vacuum boundary in spherical symmetry. Our proof relies on a new way of thinking about Einstein’s equations in spherical symmetry that is well-adapted […]

Mass for the large and for the small

CMSA Room G10 CMSA, 20 Garden Street, Cambridge, MA, United States

General Relativity Seminar Speaker: Tin Yau Tsang, Courant Institute, New York University Title: Mass for the large and for the small Abstract: Seeking a meaningful geometric (physical) invariant to describe a spacetime has sparked research in both mathematics and physics. In this talk, we will first see the fundamental progress made by Schoen-Yau and Witten […]

The Einstein-Vlasov system in a large data regime

CMSA Room G10 CMSA, 20 Garden Street, Cambridge, MA, United States

https://youtu.be/gtvSMhYhD3w General Relativity Seminar Speaker: Nikolaos Athanasiou, University of Crete, Greece Title: The Einstein-Vlasov system in a large data regime Abstract: In this talk, our object of study is the Einstein-Vlasov system with a massless Vlasov matter field. Complementing various important works obtaining the stability of Minkowski spacetime as a solution to this system, we […]

The mass angular momentum inequality

Virtual

General Relativity Seminar Speaker: Gilbert Weinstein, Ariel University Title: The mass angular momentum inequality Abstract: We show that either there is a counterexample to black hole uniqueness, in the form of a regular axisymmetric stationary vacuum spacetime with an asymptotically flat end and multiple degenerate horizons which is ‘ADM stable’, or the following statement holds. […]

On the past maximal development of near-FLRW data for the Einstein scalar-field Vlasov system

CMSA Room G10 CMSA, 20 Garden Street, Cambridge, MA, United States

General Relativity Seminar Speaker: Liam Urban (University of Vienna) Title: On the past maximal development of near-FLRW data for the Einstein scalar-field Vlasov system Abstract: In recent years, the formation of Big Bang singularities has been increasingly well understood in presence of scalar-field matter, which suppresses the geometric oscillations that one generically expects otherwise. From a cosmological perspective, […]

General Relativity Seminar

Virtual

https://youtu.be/T9D4heG-OSU General Relativity Seminar Speaker: Maximilian Ofner, University of Vienna Title: Stability and Instability of Relativistic Fluids in Slowly Expanding Spacetimes Abstract: Homogeneous and isotropic solutions to the relativistic Euler equations are known to be unstable on a Minkowski background. However, for FLRW models with a fast expansion rate, relativistic fluids stabilize. This scenario suggests […]

BKL bounces outside homogeneity

CMSA Room G10 CMSA, 20 Garden Street, Cambridge, MA, United States

https://youtu.be/g8V7VeQwDtk General Relativity Seminar Speaker: Warren Li ( Princeton University) Title: BKL bounces outside homogeneity Abstract: In work spanning the late 20th century, physicists Belinski, Khalatnikov and Lifshitz (BKL) proposed a general ansatz for solutions to the Einstein (vacuum) equations near singularities. They suggest that the spacetime dynamics at different spatial points on the singularity decouple […]

Positive scalar curvature with point singularities

CMSA Room G10 CMSA, 20 Garden Street, Cambridge, MA, United States

https://youtu.be/m9B003wQ0PY General Relativity Seminar Speaker: Rudolf Zeidler, Mathematical Institute, University of Münster Title: Positive scalar curvature with point singularities Abstract: I will explain a certain topological construction of positive scalar curvature metrics with uniformly Euclidean ($L^\infty$) point singularities. This provides counterexamples to a conjecture of Schoen. It also shows that there are metrics with uniformly Euclidean […]

Unstable Fluids in Expanding Cosmologies

Virtual

https://youtu.be/2Aak8YqVsLw General Relativity Seminar Speaker: Elliot Marshal, School of Mathematics at Monash University Title: Unstable Fluids in Expanding Cosmologies Abstract: The FLRW solution is the simplest cosmological model in general relativity, describing a fluid-filled, spatially homogeneous universe. While there is extensive literature in the physics community on cosmological models with a linear equation of state , […]

Low-regularity Local Well-posedness of the Elastic Wave System

Virtual

General Relativity Seminar Speaker: Sifan Yu, National University of Singapore Title: Low-regularity Local Well-posedness of the Elastic Wave System Abstract: In this talk, I will present a recent work on the elastic wave system in three spatial dimensions. For admissible harmonic elastic materials, we prove a low-regularity local well-posedness result for the corresponding elastic wave equations. For such materials, we can split the […]