Organizing Committee

A new era of astronomical observation was announced in 2016 when the first-ever detection of gravitational waves from a binary black hole system occurred. Gravitational waves encode detailed information about the astrophysical systems they emerge from and complement what can be learned through traditional light-based observation.

Gravitational wave science requires high-fidelity numerical simulations of the expected merger events. The Simulating eXtreme Spacetimes (SXS) collaboration has managed the development of two distinct codes for this purpose: (i) the Spectral Einstein Code (SpEC) based on pseudospectral methods, and (ii) an open-source code SpECTRE, an hp-adaptive discontinuous Galerkin scheme that also includes a sub-cell finite volume scheme in regions of strong shock formation that is ideally suited for multi-scale, multi-physics problems. SpECTRE targets problems in multi-messenger astrophysics, including neutron star mergers, core-collapse supernovae, and gamma-ray bursts. It runs at petascale and is designed for future exascale computers.

Our weeklong program includes two contemporaneous activities: (i) a focused SpEC and SpECTRE code developers meeting and (ii) a SpECTRE workshop. The code developers' meeting will bring together researchers who are actively developing these codebases. The SpECTRE workshop aims to provide graduate students, postdocs, and faculty with the tools needed to install, run, and contribute to the open-source code SpECTRE. Our SpECTRE workshop will cover topics such as the generalized harmonic formulation of the Einstein field equation, general relativistic hydrodynamics, the discontinuous Galerkin method with finite volume sub-cells, the Cauchy characteristic extraction method, installing, running, and visualizing numerical simulations, and how to get involved with code development.

Image for "Simulating Extreme Spacetimes with SpEC and SpECTRE"

Confirmed Speakers & Participants

Talks will be presented virtually or in-person as indicated in the schedule below.

  • Speaker
  • Poster Presenter
  • Attendee
  • Virtual Attendee

Application Information

ICERM welcomes applications from faculty, postdocs, graduate students, industry scientists, and other researchers who wish to participate. Some funding may be available for travel and lodging. Graduate students who apply must have their advisor submit a statement of support in order to be considered.

Application Deadline: March 12, 2024

Your Visit to ICERM

ICERM Facilities
ICERM is located on the 10th & 11th floors of 121 South Main Street in Providence, Rhode Island. ICERM's business hours are 8:30am - 5:00pm during this event. See our facilities page for more info about ICERM and Brown's available facilities.
Traveling to ICERM
ICERM is located at Brown University in Providence, Rhode Island. Providence's T.F. Green Airport (15 minutes south) and Boston's Logan Airport (1 hour north) are the closest airports. Providence is also on Amtrak's Northeast Corridor. In-depth directions and transportation information are available on our travel page.
ICERM's special rate will soon be made available via this page for our preferred hotel, the Hampton Inn & Suites Providence Downtown. ICERM also regularly works with the Graduate Hotel and Hilton Garden Inn who both have discounted rates available. Contact before booking anything.
The only way ICERM participants should book a room is through the hotel reservation links located on this page or through links emailed to them from an ICERM email address ( ICERM never works with any conference booking vendors and never collects credit card information.
Those traveling with family who are interested in information about childcare and/or schools should contact
Technology Resources
Wireless internet access ("Brown-Guest") and wireless printing is available for all ICERM visitors. Eduroam is available for members of participating institutions. Thin clients in all offices and common areas provide open access to a web browser, SSH terminal, and printing capability. See our Technology Resources page for setup instructions and to learn about all available technology.
To request special services, accommodations, or assistance for this event, please contact as far in advance of the event as possible. Thank you.
Discrimination and Harassment Policy
ICERM is committed to creating a safe, professional, and welcoming environment that benefits from the diversity and experiences of all its participants. Brown University's "Code of Conduct", "Discrimination and Workplace Harassment Policy", "Sexual and Gender-based Misconduct Policy", and "Title IX Policy" apply to all ICERM participants and staff. Participants with concerns or requests for assistance on a discrimination or harassment issue should contact the ICERM Director or Assistant Directors Kathryn Boots or Jenna Sousa; they are the responsible employees at ICERM under this policy.
Fundamental Research
ICERM research programs aim to promote Fundamental Research and mathematical sciences education. If you are engaged in sensitive or proprietary work, please be aware that ICERM programs often have participants from countries and entities subject to United States export control restrictions. Any discoveries of economically significant intellectual property supported by ICERM funding should be disclosed.
Exploring Providence
Providence's world-renowned culinary scene provides ample options for lunch and dinner. Neighborhoods near campus, including College Hill Historic District, have many local attractions. Check out the map on our Explore Providence page to see what's near ICERM.

Visa Information

Contact for assistance.

Eligible to be reimbursed
B-1 or Visa Waiver Business (WB)
Ineligible to be reimbursed
B-2 or Visa Waiver Tourist (WT)
Already in the US?

F-1 and J-1 not sponsored by ICERM: need to obtain a letter approving reimbursement from the International Office of your home institution PRIOR to travel.

H-1B holders do not need letter of approval.

All other visas: alert ICERM staff immediately about your situation.

ICERM does not reimburse visa fees. This chart is to inform visitors whether the visa they enter the US on allows them to receive reimbursement for the items outlined in their invitation letter.

Financial Support

This section is for general purposes only and does not indicate that all attendees receive funding. Please refer to your personalized invitation to review your offer.

As this program is funded by the National Science Foundation (NSF), ICERM is required to collect your ORCID iD if you are receiving funding to attend this program. Be sure to add your ORCID iD to your Cube profile as soon as possible to avoid delaying your reimbursement.
Acceptable Costs
  • 1 roundtrip between your home institute and ICERM
  • Flights on U.S. or E.U. airlines – economy class to either Providence airport (PVD) or Boston airport (BOS)
  • Ground Transportation to and from airports and ICERM.
Unacceptable Costs
  • Flights on non-U.S. or non-E.U. airlines
  • Flights on U.K. airlines
  • Seats in economy plus, business class, or first class
  • Change ticket fees of any kind
  • Multi-use bus passes
  • Meals or incidentals
Advance Approval Required
  • Personal car travel to ICERM from outside New England
  • Multiple-destination plane ticket; does not include layovers to reach ICERM
  • Arriving or departing from ICERM more than a day before or day after the program
  • Multiple trips to ICERM
  • Rental car to/from ICERM
  • Flights on a Swiss, Japanese, or Australian airlines
  • Arriving or departing from airport other than PVD/BOS or home institution's local airport
  • 2 one-way plane tickets to create a roundtrip (often purchased from Expedia, Orbitz, etc.)
Travel Maximum Contributions
  • New England: $350
  • Other contiguous US: $850
  • Asia & Oceania: $2,000
  • All other locations: $1,500
  • Note these rates were updated in Spring 2023 and superseded any prior invitation rates. Any invitations without travel support will still not receive travel support.
Reimbursement Requests

Request Reimbursement with Cube

Refer to the back of your ID badge for more information. Checklists are available at the front desk and in the Reimbursement section of Cube.

Reimbursement Tips
  • Scanned original receipts are required for all expenses
  • Airfare receipt must show full itinerary and payment
  • ICERM does not offer per diem or meal reimbursement
  • Allowable mileage is reimbursed at prevailing IRS Business Rate and trip documented via pdf of Google Maps result
  • Keep all documentation until you receive your reimbursement!
Reimbursement Timing

6 - 8 weeks after all documentation is sent to ICERM. All reimbursement requests are reviewed by numerous central offices at Brown who may request additional documentation.

Reimbursement Deadline

Submissions must be received within 30 days of ICERM departure to avoid applicable taxes. Submissions after thirty days will incur applicable taxes. No submissions are accepted more than six months after the program end.


SpECTRE Community Workshop

Group Leaders TBA

The open-source code SpECTRE is a relativistic astrophysics code for simulating neutron star mergers, core-collapse supernovae, and gamma-ray bursts. Our SpECTRE workshop aims to provide graduate students, postdocs, and faculty with the tools to install, run, and contribute to the open-source code SpECTRE. Our SpECTRE workshop will include both lectures and hand-on sessions. Lecture topics will include the generalized harmonic formulation of the Einstein field equation, general relativistic hydrodynamics, the discontinuous Galerkin method with finite volume sub-cells, and the Cauchy characteristic extraction method. There will also be ample opportunity for students and postdocs to interact with senior participants and lecturers of the ICERM workshop program.

As part of your application to the SpECTRE summer school, please briefly answer the following questions in your personal statement:

1. How does your research involve numerical relativity and/or relativistic astrophysics? 2. Do you have experience in computational physics and/or numerical relativity? Which, if any, numerical relativity codebases have you interacted with? (Note that previous experience is not required to attend the workshop.)

SXS developer meeting

Group Leaders TBA

The Simulating eXtreme Spacetimes (SXS) collaboration has overseen the development of two distinct codes — namely, the Spectral Einstein Code (SpEC) and SpECTRE — alongside the development of public simulation datasets and accompanying software for data interaction. Our upcoming in-person developers' workshop will serve as a focused forum for these codes as well as welcoming other researchers eager to contribute to these projects.

To apply for participation in the developer's meeting, please address the following questions in your personal statement:

1. Share your prior experience in developing SpEC, SpECTRE, or codes/datasets derived from simulation outputs. If you lack prior exposure to these codes, please highlight your experience with other computational relativity codes. 2. Identify the development tasks that most pique your interest for discussion or collaboration during this meeting.