The Illinois Relativity Group in the Department of Physics at the University of Illinois at Urbana-Champaign invites applications for a postdoctoral research position with focus on numerical relativity, computational astrophysics, and their applications to fundamental physics.

The successful candidate will join Prof. Helvi Witek and her team to work on numerical relativity in and beyond general relativity, including tests of gravity or modeling signatures of dark matter candidates around black holes. The candidate is intended to partially work on the Einstein Toolkit/CarpetX software framework and contribute to its hybrid Monte-Carlo/M1 neutrino transport scheme as part of the "E=mc^2 " project. This is a multi-institutional project to develop numerical infrastructure and methods, with collaborators at Louisiana State University, Rochester Institute of Technology, University of Idaho, University of Texas Austin, and the University of Wyoming, and international collaborators R. Haas and E. Schnetter.

Prof. Helvi Witek's team is currently home to postdoc Dr. Jay Kalinani, Visiting Research Scientist Dr. Elena Kopteva, six graduate students and undergraduate students; seehttps://witek-gravity-group.physics.illinois.edu. The successful candidate will become a member of the Illinois Relativity Group which includes Profs. S. Shapiro, H. O. Silva, N. Yunes, and Research Professor A. Tsokaros. They will also become part of a vibrant research community in the Illinois Center for Advanced Study of the University (ICASU;https://icasu.illinois.edu/) that bridges the Departments of Physics, Astronomy, Computer Science, Mathematics and the National Center for Supercomputing Applications (NCSA). ICASU faculty working in closely related areas include Profs. C. Gammie, G. Holder, J. Noronha-Hostler, J. Noronha, J. Shelton, and S. Vishveshwara. The successful candidate will also have opportunities to join the LISA Consortium (https://lisamission.org) and the Einstein Toolkit Consortium (https://einsteintoolkit.org).

The candidate should have a strong background in scientific software development using parallelization frameworks like MPI or in numerical relativity in and beyond General Relativity. Expertise in GPU programming is beneficial. Interested candidates must have completed a Ph.D. in astronomy, physics, or a related field before the start date.

They must submit their application package online here:https://my.physics.illinois.edu/join/under "Postdoctoral Position in Numerical Relativity and Fundamental Physics with Dr. Helvi Witek - 2026." Applicants are requested to submit:

(1) a cover letter,

(2) a curriculum vitae, including a list of publications,

(3) a research statement (limited to 3 pages, 1 inch margin, 11-12pt) containing a summary of previous and current research, and future research plans,

(4) contact information for three (3) referees who will be asked to write letters of recommendation.

The deadline for applications and all letters of recommendation is*December 1, 2025*, for full consideration. The anticipated starting date of the position is August 15, 2026, though other starting times may be negotiated. The position is expected to last for a two-year term with a potential extension to a third year, conditional on performance and/or funding availability.

Please contact Prof. Helvi Witek (hwitek@illinois.edu) if you have any questions about the position itself, or Deanna Frye (ddebord@illinois.edu) if you have any questions about the application form.

The University of Illinois System is an equal opportunity employer, including but not limited to disability and/or veteran status, and complies with all applicable state and federal employment mandates. Please visitRequired Employment Notices and Posters https://www.hr.uillinois.edu/cms/one.aspx?portalId=4292&pageId=5705to view our non-discrimination statement and find additional information about required background checks, sexual harassment/misconduct disclosures, and employment eligibility review throughE-Verify https://www.e-verify.gov/sites/default/files/everify/posters/EVerifyParticipationPoster.pdf.

Applicants with disabilities are encouraged to apply and may request a reasonable accommodation under the Americans with Disabilities Act (2008) to complete the application and/or interview process.

--------------------------------------------- Dr. Helvi Witek Associate Professor Department of Physics University of Illinois at Urbana-Champaign

247 Loomis Lab 1110 W Green St Urbana, IL 61801 ---------------------------------------------