Present: Roland H, Bill G, Beyhan K, Zhao Z, Federico C, Liu H,
Atul K, Steve B, Peter D, Alois Peter S, Chris E, Zach E, Maria BH
Chair: Roland
Minutes: Bill
* Questions before we start?
Proposed modification to the EOS_Omni thorn: I would like to discuss the possibility of including the patch to the EOS_Omni thorn proposed in the pull request that you can find at https://bitbucket.org/einsteintoolkit/einsteineos/pull-requests/6/enhancement-to-newton-raphson-and/diff and tracked in the ticket at https://bitbucket.org/einsteintoolkit/tickets/issues/2383/enhancement-to-newton-raphson-and . Although the modification may appear as minor, in my opinion, it could be relevant in some cases when adopting tabulated EOS (in particular in case of weak energy dependence on temperature).
Best Regards, Federico Cipolletta.
** Federico: Developing code and done Spritz and GRHydro and the EOS_Omni thorn may not preform well in some cases. Using EOS, 3 Dim tables, rho, temp, and electron fluctuations. Define TOV initial data based on ICs, constant entropy or temp, for example. When starting with initial data from constant temperature obtain problems during evolution. GRHydro sim stops after about 140 iterations, temp grows too large. Parameter for t_max is in GRHydro and stops the sim. While in Spritz they get the incorrect results, temp goes too high. Added check in EOS_Omni to check temperatures, rho, y, eps, and want temp. See the tickets and pull request. Interpolate values of temperature, with Newton-Raphson, if iterations are more than a value you pass to other method Bisection. Paper in 2013 noted that if dependency of energy density on temperature is weak the Newton-Raphson can overshoot and can get out of the table ranges. Lines 547 and check line 615, on the derivative, if too high goes to Bisection method, slower but more accurate.
Would like this change in a new release.
Zach: Could this change cause any trouble with existing GRHydro? Positive impression.
Federico: Proposed names for reviewers.
Roland: Would
it know if temperature is about to land outside of the valid
domain of the table? FC: Line 399 (see ticket). RH: Seem to be
depriving the user of an error message. Should run it by a high
temperature EOS user for discussion.
Peter: Do you
make sure the root is properly bracketed that is needed by
Bisection? Then guaranteed to find the solution. Do not see in
the included code. FC: Think it is done in the earlier code. In
Line 595 of Newton-Raphson, not included in the Diff shown in the
ticket.
Roland: Simple fix and will commit after this call.
gcc -O1
--help=optimizers which claims to
report the options that are used by -O1unanswered question on mailing list: https://www.einsteintoolkit.org/tools/unanswered.php
open tickets sorted by update time: https://bitbucket.org/einsteintoolkit/tickets/issues?status=open&status=new&sort=-updated_on
tickets ready for review: https://bitbucket.org/einsteintoolkit/tickets/issues?status=new&status=open&sort=-updated_on&q=Please%20review
Steve: New cactus site is https://test.cactuscode.org/
please make comments. Current site http://cactuscode.org/ . And
this move is clearly decoupled from the new release. We can do it
whenever.
New Cactus ticket https://bitbucket.org/einsteintoolkit/tickets/issues/2387/move-cactuscodeorg-to-be-hosted-by-github
Atul: BBH test, finished the figure for position of the centers and the strain. Some scaling issue compared to LIGO version. Ian Hinder's code on Mathematica, SimulationTools helps to sort that out: https://simulationtools.org/ . Peter S. will work on that. Working on Kerr Ricci scalars using Mathematica and Atul is missing a few C compilers that he needs...on his version of Mathematica on Windows. Third set of images on apparent horizons, made with VisIT. Issue page on GitHub, Roland recalls that there is a statement that you are using the intercompiler (?) to compile things. Should send a message to Users list on Einstein toolkit and on the Simulation Tools GitHub issues page, BitBucket https://bitbucket.org/simulationtools/simulationtools/issues . Atul is working on Windows with Mathematica and Steve recommends using the Linux on Windows.
* Anything else:
** Beyhan: Getting errors with core collapse control thorn in the source code, he thinks. Roland: Sounds like something is missing. Version from SVN, could be old. Post a ticket if you still have problems.
** Bill: Is anyone running VisIT in a container? Seems
not---will find a way to run it.
Roland: Vote next week for Feature Freeze. Take a look
at the new codes being included.
===================================== William Gabella Research Assistant Professor Department of Physics and Astronomy Vanderbilt University Nashville, TN USA b.gabella@vanderbilt.edu (o) 615-343-2713