Present: Leo, Roland, Peter, Steve, Zach, Beyhan, Deborah, Johnny, Keith, Lucas, Nikolai
Chair: Leo Minutes: Roland
ET EU meeting 2025 discussion =============================
* Beyhan reported on numbers of attending participants * recordings and slides are available at https://sites.google.com/view/eetk25 * minutes of discussion will be added soon * next US meeting will be at UIUC * next EU meeting is TBD
ET 2026 release ===============
* Steve is chair * Roland is future chair * Beyhan agreed to help * Deborah agrees to help with gallery runs * Lucas volunteers to run gallery examples * Johnny agrees to run gallery
* Roland mentions that BHNS gallery example should be in the making * Roland suggests that having a BNS example that is not using LORENE and GRHydro would be nice * Leo and Peter suggest that using FUKA as ID reader is not too expensive * Beyhan suggests that SGRID would offer more options for initial data ** Steve and Peter suggest reaching out to Wolfgang Tichy for an introduction
Questions on the mailing list =============================
Older messages since from before US Thanksgiving
* "Loss of convergence with subcycling in time" https://lists.einsteintoolkit.org/pipermail/users/2025-November/009815.html Steve is concerned about lack of convergence, Erik pointed out that full Christmas tree scheme must be used that does not use any interpolation in time at all
* "Safe check of variable Coordinates::volume_form_state" https://lists.einsteintoolkit.org/pipermail/users/2025-November/009821.html Suggest to create a ticket since this seems to be a bug. Storage itself can always be checked via CCTK_VarDataPtr
Tickets on list ===============
* "BHNS with Elliptica: Assertion `all(offset == other.offset)' failed" https://bitbucket.org/einsteintoolkit/tickets/issues/2899/ . No progress, Roland now has access to MN5.
* "CarpetX: interpolation with z-reflection symmetry only works for Psi4", https://bitbucket.org/einsteintoolkit/tickets/issues/2902 . Roland says this would be nice to have for upcoming release.
* "NoiseX: Improve noise generation in CarpetX", https://bitbucket.org/einsteintoolkit/tickets/issues/2855 . Moved to top since Roland added comment based on Erik's observation that vertex centered grid double cover the last grid point
* "CarpetX: Interpolator caches" https://bitbucket.org/einsteintoolkit/tickets/issues/2898 . Lucas is re-implementing so as to not use a cache but provide finer grained control to caller over stages (setup and interpolate)
* "GetComponents: add support to set push_url in git" https://bitbucket.org/einsteintoolkit/tickets/issues/2896 Steve will review
* "PUGH tries to free memory not allocated by malloc", https://bitbucket.org/einsteintoolkit/tickets/issues/2764 . No progress.
* "Improve McLachlan accuracy", https://bitbucket.org/einsteintoolkit/tickets/issues/963 . Peter and Zach are still working on this.
Any other business ==================
* Roland mentioned prior efforts of transitioning Cactus codes to github and need to reach out to current owner of cactuscode github user name
* Lucas brought up the issue that Perl is becoming less and less familiar to developers of Cactus code. Suggests to try and see if a transition to Python (3) maybe using a LLM to help it possible. Need to ensure that a common version of Python 3 is installed on all clusters.
We will meet once more this year next week (Dec 18th), then skip Christmas day (25th) and New Year's day (1st).
Next chair: Deborah Next minutes: Nikolai
Yours, Roland