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Getting started

• Guide to getting started
• Partial list of supported compilers
• Thorns using CarpetX
• Mailing list
• Chat channel
• Join the weekly phone call Wed 10am US Eastern Time.

Workshops and hackathons

• 2023 Frontier Hackathon
• 2023 ET RIT workshop
• 2022 NERSC Hackathon
• 2022 ET UIdaho workshop

Presentations

• 2023 NewRadX introduction
• 2022 ET US meeting at UIDaho
• 2021 ET US meeting at UIllinois
• 2021 ET User call

CarpetX ideas

• ideas: call scheduled functions with full MFab: done
• ideas: use OpenMP tasking or similar to have a more task based
  scheduling
• work item ideas
• virtual function on GPUs

CarpetX implementation tasks

• vertex centered grid functions by default: done
• test multi-node GPU support: done
• checkpoint / restart: done
• test a qc0 run or similar to compare results and speed to Carpet w/o subcycling in time
• subcycling in time, likely using runge-kutta prolongation
  • allow flexibiliy of subcycling vs no subcycling on a per level case, currently partially implemented
  • lead by Liwei Ji @lwJi, code at: https://github.com/lwJi/Infino.jl/tree/main
  • ET wiki with information: https://docs.einsteintoolkit.org/et-docs/Prolongation
  • CarpetX prolongation and subcycling notes
• Con2Prim: as a first step we will use Reprimand to reduce the complexity of code we implement. Instructions for this are found here

CarpetX desired feature list

Science runs would be say a MHD driven supernova with tracer particles and a neutrino evolution scheme. This would require these abilities:

• cell centered (volume averaged) grid with AMR for fluid: done 
• vertex centered (sampled) grid with AMR for metric: done
• staggered grid for magnetic field
• subcycling in time
  • Runge-Kutta prolongation into mesh refinement boundaries to avoid "buffer" zones (which AMReX may not support)
  • notes on the Einstein Toolkit wiki
• some sort refluxing for fluid due to subcycling in time
• some sort of monopole avoiding prolongation scheme for B
• some sort of scheme that conserves magnetic flux at mesh refinement boundaries
• support for 2D (prevent refinement in the Z-direction)
• interpolators to get values of fields at particle locations: done
• reduction operators for min, max, sum etc.: done
• checkpoint and recovery: done
• 3d output for visualization: done
• GPU support
  • for RHS calculation: done
  • for AMR operators: done
  • for everything else