There are no events at the Simons Center today. Here are the events for this week
Monday, March 30th, 2026
Program Mini Course: Herman Verlinde
Time: 11:15 AM - 12:45 PM
Location: SCGP 313
Title: Holography for Mathematicians
Title: Holography for Mathematicians
Program Mini Course: Herman Verlinde
Time: 2:00 PM - 3:30 PM
Location: SCGP 313
Title: Holography for Mathematicians
Title: Holography for Mathematicians
Simons Lecture Series by Michael Hutchings (UC Berkeley)
Time: 2:15 PM - 3:30 PM
Location: 103
Title: Dynamics of Reeb vector fields in three dimensions
Abstract: We review various recent results on the existence and properties of periodic orbits of Reeb vector fields in three dimensions. The results we will discuss can be proved using spectral invariants in embedded contact homology. Many of these results can also be proved using a new, simplified version of these invariants, called "elementary spectral invariants". The elementary spectral invariants are defined as a max-min energy of pseudoholomorphic curves satisfying certain constraints, inspired by a construction of McDuff-Siegel. In the first lecture we will introduce the results on Reeb dynamics that we will be discussing. In the second lecture we will state the axiomatic properties of the elementary spectral invariants and explain how these can be used to obtain results on Reeb dynamics. In the third lecture we will describe the construction of elementary spectral invariants. Lecture 1: Recent results in three-dimensional Reeb dynamics
Title: Dynamics of Reeb vector fields in three dimensions
Abstract: We review various recent results on the existence and properties of periodic orbits of Reeb vector fields in three dimensions. The results we will discuss can be proved using spectral invariants in embedded contact homology. Many of these results can also be proved using a new, simplified version of these invariants, called "elementary spectral invariants". The elementary spectral invariants are defined as a max-min energy of pseudoholomorphic curves satisfying certain constraints, inspired by a construction of McDuff-Siegel. In the first lecture we will introduce the results on Reeb dynamics that we will be discussing. In the second lecture we will state the axiomatic properties of the elementary spectral invariants and explain how these can be used to obtain results on Reeb dynamics. In the third lecture we will describe the construction of elementary spectral invariants. Lecture 1: Recent results in three-dimensional Reeb dynamics
Tuesday, March 31st, 2026
Program Mini Course: Herman Verlinde
Time: 11:15 AM - 12:45 PM
Location: SCGP 313
Title: Holography for Mathematicians
Title: Holography for Mathematicians
Simons Lecture Series by Michael Hutchings (UC Berkeley)
Time: 2:15 PM - 3:30 PM
Location: 102
Title: Dynamics of Reeb vector fields in three dimensions
Abstract: We review various recent results on the existence and properties of periodic orbits of Reeb vector fields in three dimensions. The results we will discuss can be proved using spectral invariants in embedded contact homology. Many of these results can also be proved using a new, simplified version of these invariants, called "elementary spectral invariants". The elementary spectral invariants are defined as a max-min energy of pseudoholomorphic curves satisfying certain constraints, inspired by a construction of McDuff-Siegel. In the first lecture we will introduce the results on Reeb dynamics that we will be discussing. In the second lecture we will state the axiomatic properties of the elementary spectral invariants and explain how these can be used to obtain results on Reeb dynamics. In the third lecture we will describe the construction of elementary spectral invariants. Lecture 2: Elementary spectral invariants and applications
Title: Dynamics of Reeb vector fields in three dimensions
Abstract: We review various recent results on the existence and properties of periodic orbits of Reeb vector fields in three dimensions. The results we will discuss can be proved using spectral invariants in embedded contact homology. Many of these results can also be proved using a new, simplified version of these invariants, called "elementary spectral invariants". The elementary spectral invariants are defined as a max-min energy of pseudoholomorphic curves satisfying certain constraints, inspired by a construction of McDuff-Siegel. In the first lecture we will introduce the results on Reeb dynamics that we will be discussing. In the second lecture we will state the axiomatic properties of the elementary spectral invariants and explain how these can be used to obtain results on Reeb dynamics. In the third lecture we will describe the construction of elementary spectral invariants. Lecture 2: Elementary spectral invariants and applications
Wednesday, April 1st, 2026
YITP Event: YITP Seminar Speaker: Bryce Cyr MIT
Time: 9:45 AM - 10:45 AM
Location:
Title: CMB Spectral Distortions: The HOW, WHAT, and WHEN?
Abstract: In this talk, I will boldly attempt to cover the formalism, applications, and experimental prospects of future CMB spectrometers, aimed at measuring small deviations to the blackbody nature of the cosmic microwave background. I will begin with a gentle introduction to the cosmological thermalization problem, providing general motivation from both within and outside of the so-called standard models of cosmology and particle physics. Following this, I will show how current experimental data (from the 1990's) can be used to constrain dark photons and dark atomic sectors, highlighting the potential gain in sensitivity that would come from a next-generation experiment such as FOSSIL or PIXIE. Finally, I will conclude with an overview of the experimental landscape, which after over two decades of inactivity, has had a flurry of exciting recent developments.
Title: CMB Spectral Distortions: The HOW, WHAT, and WHEN?
Abstract: In this talk, I will boldly attempt to cover the formalism, applications, and experimental prospects of future CMB spectrometers, aimed at measuring small deviations to the blackbody nature of the cosmic microwave background. I will begin with a gentle introduction to the cosmological thermalization problem, providing general motivation from both within and outside of the so-called standard models of cosmology and particle physics. Following this, I will show how current experimental data (from the 1990's) can be used to constrain dark photons and dark atomic sectors, highlighting the potential gain in sensitivity that would come from a next-generation experiment such as FOSSIL or PIXIE. Finally, I will conclude with an overview of the experimental landscape, which after over two decades of inactivity, has had a flurry of exciting recent developments.
YITP Event: YITP Seminar Speaker: Maximilian Lutz Max Planck Institute
Time: 11:00 AM - 12:00 PM
Location:
Program Talk: Alicia Castro
Time: 11:15 AM - 12:45 PM
Location: SCGP 313
Title: Random geometries in various quantum gravity approaches
Abstract: The gravitational path integral involves a sum over geometries weighted by the exponential of the gravitational action. In certain quantum gravity (QG) models, this sum admits a precise probabilistic interpretation, namely as the partition function of random geometries. This perspective allows one to apply tools from random geometry, such as random maps and matrix and tensor models, to the study of QG. In this talk, I will give an overview of the different models I have worked on, including random maps, random hyperbolic surfaces, and random tensor models, and discuss their applications to quantum gravity, with examples ranging from JT gravity to dynamical triangulations.
Title: Random geometries in various quantum gravity approaches
Abstract: The gravitational path integral involves a sum over geometries weighted by the exponential of the gravitational action. In certain quantum gravity (QG) models, this sum admits a precise probabilistic interpretation, namely as the partition function of random geometries. This perspective allows one to apply tools from random geometry, such as random maps and matrix and tensor models, to the study of QG. In this talk, I will give an overview of the different models I have worked on, including random maps, random hyperbolic surfaces, and random tensor models, and discuss their applications to quantum gravity, with examples ranging from JT gravity to dynamical triangulations.
Simons Lecture Series by Michael Hutchings (UC Berkeley)
Time: 2:15 PM - 3:30 PM
Location: 102
Title: Dynamics of Reeb vector fields in three dimensions
Abstract: We review various recent results on the existence and properties of periodic orbits of Reeb vector fields in three dimensions. The results we will discuss can be proved using spectral invariants in embedded contact homology. Many of these results can also be proved using a new, simplified version of these invariants, called "elementary spectral invariants". The elementary spectral invariants are defined as a max-min energy of pseudoholomorphic curves satisfying certain constraints, inspired by a construction of McDuff-Siegel. In the first lecture we will introduce the results on Reeb dynamics that we will be discussing. In the second lecture we will state the axiomatic properties of the elementary spectral invariants and explain how these can be used to obtain results on Reeb dynamics. In the third lecture we will describe the construction of elementary spectral invariants. Lecture 3: Construction of elementary spectral invariants
Title: Dynamics of Reeb vector fields in three dimensions
Abstract: We review various recent results on the existence and properties of periodic orbits of Reeb vector fields in three dimensions. The results we will discuss can be proved using spectral invariants in embedded contact homology. Many of these results can also be proved using a new, simplified version of these invariants, called "elementary spectral invariants". The elementary spectral invariants are defined as a max-min energy of pseudoholomorphic curves satisfying certain constraints, inspired by a construction of McDuff-Siegel. In the first lecture we will introduce the results on Reeb dynamics that we will be discussing. In the second lecture we will state the axiomatic properties of the elementary spectral invariants and explain how these can be used to obtain results on Reeb dynamics. In the third lecture we will describe the construction of elementary spectral invariants. Lecture 3: Construction of elementary spectral invariants
Math Event: Algebraic Geometry Seminar: Tong Zhou - The microlocal theory of constructible sheaves
Time: 4:00 PM - 5:00 PM
Location:
Speaker: Tong Zhou
Abstract: The microlocal point of view says that the study of an object on a manifold benefits from systematic constructions involving the cotangent bundle. It was introduced by M. Sato in the 1960s in the field of partial differential equations, and has since spread to many other fields. In this talk, I will first introduce the basic ingredients of the microlocal theory of sheaves on manifolds as developed by M. Kashiwara and P. Schapira, then I will discuss recent developments and open questions in the analogous theories in the positive characteristic algebraic context and the non-Archimedean analytic context.
Speaker: Tong Zhou
Abstract: The microlocal point of view says that the study of an object on a manifold benefits from systematic constructions involving the cotangent bundle. It was introduced by M. Sato in the 1960s in the field of partial differential equations, and has since spread to many other fields. In this talk, I will first introduce the basic ingredients of the microlocal theory of sheaves on manifolds as developed by M. Kashiwara and P. Schapira, then I will discuss recent developments and open questions in the analogous theories in the positive characteristic algebraic context and the non-Archimedean analytic context.
Thursday, April 2nd, 2026
Program Mini Course: Zhenbin Yang
Time: 11:15 AM - 12:45 PM
Location: SCGP 313
Title: Review of JT Gravity Part 1
Title: Review of JT Gravity Part 1
Program Mini Course: Zhenbin Yang
Time: 2:00 PM - 3:30 PM
Location: SCGP 313
Title: Review of JT Gravity Part 2
Title: Review of JT Gravity Part 2
Math Event: Colloquium: Alex Cohen - Developments in projection theory
Time: 2:15 PM - 3:15 PM
Location: Math Tower P-131
Speaker: Alex Cohen
Abstract: Given a set X in R^d and a collection of projections from R^d -> R^m, how large is a typical projection of X? This is the basic question of projection theory, and it is a central node in a network of related problems spanning additive combinatorics, incidence geometry, harmonic analysis, dynamics, and more. Recent years have seen a sequence of breakthroughs, two highlights being Ren-Wang-Orponen-Shmerkin's proof of the Furstenberg set conjecture in R^2 and Wang-Zahl's proof of the Kakeya set conjecture in R^3. Both proofs share two key ingredients, developed over many papers: Lots of induction on scales to reduce the problem to a special case with arithmetic structure, and additive combinatorics to solve this special case. I will attempt to explain how induction on scales is used, focusing on the special case of R^2 -> R.
Speaker: Alex Cohen
Abstract: Given a set X in R^d and a collection of projections from R^d -> R^m, how large is a typical projection of X? This is the basic question of projection theory, and it is a central node in a network of related problems spanning additive combinatorics, incidence geometry, harmonic analysis, dynamics, and more. Recent years have seen a sequence of breakthroughs, two highlights being Ren-Wang-Orponen-Shmerkin's proof of the Furstenberg set conjecture in R^2 and Wang-Zahl's proof of the Kakeya set conjecture in R^3. Both proofs share two key ingredients, developed over many papers: Lots of induction on scales to reduce the problem to a special case with arithmetic structure, and additive combinatorics to solve this special case. I will attempt to explain how induction on scales is used, focusing on the special case of R^2 -> R.