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COVID-19 Information for ICERM Participants

Due to the COVID-19 pandemic, Brown University has instructed the majority of staff to work from home through December 23, 2020. ICERM's physical space is closed to visitors and to the public. A very limited number of accepted long-term visitors will be in-residence this fall. Our programming will continue online. Check out the event pages for schedules and more details.

ICERM will continue to follow precautions from Brown as well as local, state, and national guidelines to protect program participants and staff from the novel coronavirus COVID-19. For more details, please see the university's FAQ page.

#### This Week at ICERM

##### Advances in Computational Relativity

Sep 9 - Dec 11, 2020

The Nobel-Prize-winning detection of gravitational waves from binary black hole systems in 2015 by the Laser Interferometer Gravitational-Wave Observatory (LIGO) and the LIGO Scientific Collaboration has opened a new window on the universe. In addition, the 2017 observation of both gravitational and electromagnetic waves emitted by a binary neutron star system marked a new era of multi-messenger astronomy. While these successes are a remarkable experimental feat, they also constitute a significant computational achievement due to the crucial role played by accurate numerical models of the astrophysical sources in gravitational-wave data analysis. As current detectors are upgraded and new detectors come online within an international network of observatories, accurate, efficient, and advanced computational methods will be indispensable for interpreting the diversity of gravitational wave signals. This semester program at ICERM will emphasize the fundamental mathematical and... (more)

##### Organizing Committee

- Stefanos Aretakis
- Douglas Arnold
- Manuela Campanelli
- Scott Field
- Jonathan Gair
- Jae-Hun Jung
- Gaurav Khanna
- Stephen Lau
- Steven Liebling
- Deirdre Shoemaker
- Jared Speck
- Saul Teukolsky

##### A Virtual ICERM Public Lecture: Uncovering Lottery Shenanigans

Sep 22, 2020

It is very rare to meet anyone who has won a prize worth at least $600 or more in the lottery. (You could expect to buy thousands of scratcher tickets before winning such a prize.) Nonetheless, when looking at publicly-available data, we discovered that some individuals had won hundreds of these big prizes! That much success smelled fishy. We wondered: are they up to something? This talk will describe the data we saw, what mathematics had to say about it, and the legal and illegal schemes that on-the-ground investigations revealed.

This webinar event will be recorded live and made available via ICERM's video archive.

#### Upcoming Programs

##### ONLY OFFERED VIRTUALLY: Mathematical and Computational Approaches for Solving the Source- Free Einstein Field Equations

Oct 5 - 9, 2020

This workshop will focus on theoretical and computational approaches to solving the vacuum Einstein field equations (the master equation of general relativity: a nonlinear, coupled, hyperbolic-elliptic PDE system) without matter field sources. A particular important special case is the simulation of two merging black holes, which will be emphasized throughout the workshop. Gravitational wave solutions will be another important aspect of this workshop, and special attention will be given to modeling techniques for the computation of these waves. The topics covered in this workshop will be relevant to both LIGO and LISA scientific efforts.

##### Organizing Committee

- Stefanos Aretakis
- Scott Field
- Jan Hesthaven
- Jae-Hun Jung
- Gaurav Khanna
- Stephen Lau
- Steven Liebling
- Deirdre Shoemaker
- Jared Speck
- Helvi Witek

##### A Virtual ICERM Public Lecture: One Person, One Vote

Oct 20, 2020

About a quarter of Americans report believing that double voting is a relatively common occurrence, casting doubt on the integrity of elections. But, despite a dearth of documented instances of double voting, it’s hard to know how often such fraud really occurs (people might just be good at covering it up!). I’ll describe a simple statistical trick to estimate the rate of double voting -- one that builds off the classic birthday paradox -- and show that such behavior is exceedingly rare. I’ll further argue that current efforts to prevent double voting can in fact disenfranchise many legitimate voters.

##### ONLY OFFERED VIRTUALLY: Mathematical and Computational Approaches for the Einstein Field Equations with Matter Fields

Oct 26 - 30, 2020

This workshop will focus on theoretical and computational approaches to solving the Einstein field equations (the master equation of general relativity: a nonlinear, coupled, hyperbolic-elliptic PDE system) with (fluid) matter field sources, as typical of binary neutron stars and supernovae. Simulations of these systems are targets of interest to both LIGO and telescopes such as Hubble, Fermi, and CHANDRA. In this workshop, special attention will be given to the governing equations of relativistic (magneto- ) hydrodynamics and multi-scale, multi-physics modeling challenges.

##### Organizing Committee

- Stefanos Aretakis
- Manuela Campanelli
- Scott Field
- Jan Hesthaven
- Gaurav Khanna
- Luis Lehner
- Steven Liebling
- Jared Speck

##### A Virtual ICERM Public Lecture: Featuring Jonathan Mattingly

Oct 28, 2020

Coming soon!

##### ONLY OFFERED VIRTUALLY: Statistical Methods for the Detection, Classification, and Inference of Relativistic Objects

Nov 16 - 20, 2020

This workshop will focus on data analysis strategies for comparing model predictions to data. Special attention will be placed on comparing solutions to the Einstein field equations (as in workshops 2 and 3) with data collected from gravitational-wave or telescopes. The workshop will include (but will not be limited to) coverage of topics involving reduced-order models, surrogate models, machine learning, UQ, and Bayesian techniques.

##### Organizing Committee

- Sara Algeri
- Sarah Caudill
- Katerina Chatziioannou
- Alessandra Corsi
- Scott Field
- Jonathan Gair
- Jae-Hun Jung
- Gaurav Khanna

##### Combinatorial Algebraic Geometry

Feb 1 - May 7, 2021

Combinatorial algebraic geometry comprises the parts of algebraic geometry where basic geometric phenomena can be described with combinatorial data, and where combinatorial methods are essential for further progress.

Research in combinatorial algebraic geometry utilizes combinatorial techniques to answer questions about geometry. Typical examples include predictions about singularities, construction of degenerations, and computation of geometric invariants such as Gromov-Witten invariants, Euler characteristics, the number of points in intersections, multiplicities, genera, and many more. The study of positivity properties of geometric invariants is one of the driving forces behind the interplay between geometry and combinatorics. Flag manifolds and Schubert calculus are particularly rich sources of invariants with positivity properties.

In the opposite direction, geometric methods provide powerful tools for studying combinatorial objects. For example, many deep properties of... (more)

##### Organizing Committee

- Anders Buch
- Melody Chan
- June Huh
- Thomas Lam
- Leonardo Mihalcea
- Sam Payne
- Lauren Williams

#### Connect with ICERM

##### NSF Grant Renews ICERM through 2025

**July 13, 2020** - ICERM received the largest National Science Foundation grant in Brown University's history. The $23.7M grant will support the institute's continuing mission to broaden the relationship between mathematics and computation for the next five years and enable the expansion of cutting-edge programming. Read more

##### Addressing racial injustice

**June 9, 2020** - ICERM joins Brown University in its message about confronting racial injustice.

##### ICERM Newsletter Spring 2020

###### Spring 2020 - In This Issue:

- COVID-19 Plan
- ICERM Funding Advisory
- Call for Proposals
- Upcoming Programs