Users October 2025

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18 participants
27 discussions

Postdoctoral Position in Numerical Relativity and Fundamental Physics at the University of Illinois Urbana-Champaign
by Helvi Witek 26 Nov '25

26 Nov '25

Dear all, we are inviting applications for a postdoctoral position in numerical relativity and fundamental physics at the University of Illinois Urbana-Champaign. The successful candidate will work with Prof. Helvi Witek and her team, and they will have the opportunity to collaborate on the Einstein Toolkit/CarpetX software framework. Applicant should submit their application package (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, by *December 1, 2025*, here:https://my.physics.illinois.edu/join/under “Postdoctoral Position in Numerical Relativity and Fundamental Physics with Dr. Helvi Witek – 2026.” The prospective start date of the position is August 2026. Please find the detailed announcement below. Best wishes Helvi --- 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(a)illinois.edu) if you have any questions about the position itself, or Deanna Frye (ddebord(a)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=5705>to 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/EVerifyPartici…>. 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 ---------------------------------------------

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Meeting minutes for 2025-10-30
by Deborah Ferguson 30 Oct '25

30 Oct '25

October 30, 2025 Minutes Chair: Steve Minutes: Deborah Attendees: Roland, Deborah, Peter, Steve, Lucas, Keith, Zach, Nikolai, Leo, Johnny BBH Gallery example Rhiannon having some permission errors with adding the results Roland will respond with solutions ET Server Updates Nothing to report Tutorial server is live for development for December meeting Contact Steve for login info EU ETK workshop No update Has been added to main ETK page Unanswered questions Issues running BNS dies with an assertion error Roland will look into it Open tickets ExternalLibraries/AMReX: New configuration variable Roland has done it Tickets for review 2860 Just approved by Peter ----------------------------------------- Deborah Ferguson Assistant Professor The University of Rhode Island

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Einstein Toolkit Meeting Reminder
by users＠einsteintoolkit.org 29 Oct '25

29 Oct '25

Hello, Please consider joining the weekly Einstein Toolkit phone call at 9:00 am US central time on Thursdays. For details on how to connect and what agenda items are to be discussed, use the link below. ** DAYLIGHT SAVING TIME WARNING ** Please note that the US / EU has already / not yet transitioned to / from daylight saving time. The phone call will be at 15:00 Central EU time. https://docs.einsteintoolkit.org/et-docs/Main_Page#Weekly_Users_Call --The Maintainers

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Fwd: Postdoctoral Position in Numerical Relativity and Fundamental Physics at the University of Illinois Urbana-Champaign
by Roland Haas 28 Oct '25

28 Oct '25

Hello all, Apparently I messed up in my previous attempt to forward Helvi's announcement (technical reason: the text got included as a "binary" attachment, due to utf-8 characters). In any case, below please find the original announcement (which some of you may have received via other mailing lists and / or the ET mailing list already. Email lists are getting harder to due to enhanced spam filters everywhere.). Yours, Roland Begin forwarded message: Date: Mon, 27 Oct 2025 21:26:11 -0500 From: Helvi Witek <hwitek(a)illinois.edu> Dear all, we are inviting applications for a postdoctoral position in numerical relativity and fundamental physics at the University of Illinois Urbana-Champaign. The successful candidate will work with Prof. Helvi Witek and her team, and they will have the opportunity to collaborate on the Einstein Toolkit/CarpetX software framework. Applicant should submit their application package (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, by *December 1, 2025*, here:https://my.physics.illinois.edu/join/under “Postdoctoral Position in Numerical Relativity and Fundamental Physics with Dr. Helvi Witek – 2026.” The prospective start date of the position is August 2026. Please find the detailed announcement below. Best wishes Helvi --- 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(a)illinois.edu) if you have any questions about the position itself, or Deanna Frye (ddebord(a)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=5705>to 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/EVerifyPartici…>. 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 --------------------------------------------- -- My email is as private as my paper mail. I therefore support encrypting and signing email messages. Get my PGP key from http://pgp.mit.edu . _______________________________________________ Users mailing list Users(a)einsteintoolkit.org http://lists.einsteintoolkit.org/mailman/listinfo/users

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Postdoctoral Position in Numerical Relativity and Fundamental Physics at the University of Illinois Urbana-Champaign
by Helvi Witek 28 Oct '25

28 Oct '25

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.Â The candidate is intended to partially work on theÂ 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 projectÂ to develop numerical infrastructure and methods,Â 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 inÂ numerical relativity in and beyond General Relativity. Expertise in GPU programming is beneficial.Â 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."Â 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(a)illinois.edu) if you have any questions about the position itself, or Deanna Frye (ddebord(a)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=5705>to 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/EVerifyPartici…>. 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 ---------------------------------------------

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Agenda for Thursday's Meeting
by users＠einsteintoolkit.org 27 Oct '25

27 Oct '25

Please update the Wiki with agenda items for Thursday's meeting. Thanks! https://docs.einsteintoolkit.org/et-docs/meeting_agenda --The Maintainers

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Unexpected slowdown when increasing Carpet::max_refinement_levels (no AMR active)
by Naseri, Mahdi - (mahdinaseri) 25 Oct '25

25 Oct '25

Hello, I’m seeing an unexpected performance drop in Carpet (ET). I ran two simulations with identical parameter files (attached) except for: Carpet::max_refinement_levels = 9 (Run A) Carpet::max_refinement_levels = 12 (Run B) During the period I conducted this experiment, all the refinement levels were inactive except for the base level. Therefore, I expected to see the same performance in both Runs A and B, because the active grid structure is the same. However, I realized that Run B is almost 4 times slower than Run A; a plot of wall-clock time per simulation time for these two simulations is also attached for comparison. Is this behavior known/expected (e.g., due to bookkeeping, allocation, or scheduling costs that scale with the allowed number of levels), or does it suggest a configuration issue on my side? Any pointers on what to check, or how to profile this within Carpet/Cactus, to understand the overhead would be greatly appreciated. Thank you, Mahdi Naseri

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PhD position in Numerical Relativity, Jena, Germany
by Sebastiano Bernuzzi 25 Oct '25

25 Oct '25

Dear Colleague, Applications are invited for a PhD position in Numerical Relativity at the Theoretical Physics Institute (TPI) FSU Jena, Germany. The successful applicant will join the team led by Prof. Sebastiano Bernuzzi and work on numerical relativity simulations of neutron star mergers. The position is part of a cross-border project between Jena and Prof. David Radice’s group at Penn State University (USA). The project is funded by the Deutsche Forschungsgemeinschaft (DFG) and the US National Science Foundation (NSF) under the DFG-NSF Physics initiative. Candidates with background in numerical relativity, relativistic astrophysics and/or multi-messenger astrophysics with neutron star mergers are encouraged to apply. The application should be sent by e-mail to ‘sebastiano.bernuzzi[AT] uni-jena.de’ by November 2nd, 2025. Review of the applications shall start immediately after that date; short-listed candidates will be invited for interviews. Please submit a *single* PDF file via Email and use as subject: ‘Application for PhD position – SURNAME NAME’. Candidates should submit the following documents: 1. a copy of their MSc diploma or a binding statement of its date of completion together with exam results, 2. a CV including the list of publications, 3. a short statement of research achievements and interests (maximum 2 pages). Applicants should arrange for letters of recommendation to be sent directly to the same E-mail address above. LINK: https://www.physik.uni-jena.de/2405/stellen S.Bernuzzi

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Inconsistency warnings: cores/threads mismatch [Leonardo cluster]
by IOSIF PANAGIOTIS 24 Oct '25

24 Oct '25

Hi all, After having installed the toolkit on Leonardo, CINECA, I wanted to try the TOV examples. However, I am getting the following warnings: Warning: Too many threads per process specified: specified num-threads=56 (ppn-used is 112) Warning: Total number of threads and number of threads per process are inconsistent: procs=16, num-threads=56 (procs*num-smt must be an integer multiple of num-threads) Warning: Total number of threads and number of cores per node are inconsistent: procs=16, ppn-used=112 (procs must be an integer multiple of ppn-used) >From those, it seems that I am doing something wrong either in my machine.ini file or in the resources request when submitting the job. Here is the command I use to run the TOV example: ./simfactory/bin/sim submit tov_ET --parfile par/tov_ET.par --cores 16 --walltime 00:20:00 And here is the ini file I am using (the "Cluster characteristics" section is identical to Bruno Giacomazzo's file<https://bitbucket.org/simfactory/simfactory2/commits/0d4011bf554ee695f9543e…>: https://github.com/piosif/einstein-toolkit-config-leonardo/blob/main/leonar… The job ran and completed fine, but from what I understand, it ran on 56 cores instead of the 16 that I requested. >From what I understand, the problem is that I am requesting just 16 cores for this simple test, but due to the cluster specs in the ini file, SimFactory expects me to request a multiple of 56. Is that so? So, my question is the following: * I want to do some tests, running a single star e.g. on a single node using 16, 32, 64 cores (to understand the timescale required). Do I need to change my ini file? * Or is there some option to specify when submitting the job that will override the cluster specs? I read the simfactory's terminology explanation on nodes, threads etc<https://simfactory.bitbucket.io/simfactory2/userguide/processterminology.ht…>, but it is not clear to me how to request the cores I need. Best, Panayotis

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Meeting Minutes 2025-10-23
by Bill Gabella 23 Oct '25

23 Oct '25

Minutes for the Einstein Toolkit Meeting, 20251023 https://docs.einsteintoolkit.org/et-docs/Main_Page#Weekly_Users_Call 9am CDT Thursdays Present: Steve B, Deborah F, Peter D, Beyhan K, Zach E, Bill G, Leo W, Keith D, Nikolai Chair: Deborah F Minutes: Bill G * BBH gallery example (Zach) -- Leo, not done yet. * ET Server updates -- Steve, The Wiki is being updated and people at LSU. Work in progress and not ready. * EU ET school and workshop -- Beyhan, talking to people. Check-in with Zach on tutorial, title (NRPy) and request to talk about GPU Programming. Peter agrees to the TOV example, will let Beyhan know if that is any change. Deborah will send him her talk title. Registration https://sites.google.com/view/eetk25 Draft Program https://sites.google.com/view/eetk25/programme * Unanswered email https://www.einsteintoolkit.org/tools/unanswered.php Castillo email, Steve will (did) respond. Sandeep email, Looks like Roland is handling this. Difficult to see new information in long thread. Panagiotis email, Long thread with two unanswered questions, about memory (--memory?) and how to request one full node. No one seems to know about the --memory option. Steve will respond to the second point...see ini attached in the file. * Open Tickets https://bitbucket.org/einsteintoolkit/tickets/issues?status=open&status=new… #2892, SpacetimeX... Liwei is helping and it is moving along. Miren has posted to the AMReX Slack. #2890, CarpetX: crash/failed... Liwei working with the same person, Miren. #2894, CarpetX: Support multipatch... Roland seems to have some questions. #2893, CarpetX: remove LEVEL=9... Group not sure what this is. Is a Pull Request. Lucas is asking for review. #2891, ExternalLIbraries/AMReX... Roland has been assigned. Very recent from Erik S. #2866, Problem while building the Et... Lucas is going to look at this; he has access to the cluster. #2889, Outflow uses incorrect... Pull Request ready to review. This is a BUG fix. * Tickets ready for review https://bitbucket.org/einsteintoolkit/tickets/issues?status=new&status=open… #2894, CarpetX: Support multipatch... Roland has questions. #2893, CarpetX: remove LEVEL=9... Pull request. #2889, Outflow uses incorrect... Roland changed status to Open. Discuss next week; is a BUG fix. #2764, PUGH tries to free memory... Beyhan has not had a chance but will look at it. #963, Improve McLachlan accuracy Peter, this is ongoing and is testing this now. #2855, NoiseX: Improve noise generation... Noise generation/Random Number Generation not consistent when using the same seed. Lucas is looking at this and considering using his own implementation. o Any Other Business Next Meeting, Thursday, 30 October 2025. https://docs.einsteintoolkit.org/et-docs/Meeting_agenda CarpetX wiki https://github.com/EinsteinToolkit/CarpetX/wiki CarpetX zoom https://ubc.zoom.us/j/66033196685?pwd=zxXTpcrBY1L7nT2kNFITm71ZuoZEiO.1 FYI, bill e.g. -- Home Page <https://gabella.github.io/index.html> LinkedIn <https://www.linkedin.com/in/bill-gabella-350b016/>

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