Pencil Code school and 2025 user meeting

Contribution List

2. Welcome to Pencil Code school

Alberto Roper Pol, Axel Brandenburg (Nordita)

10/20/25, 9:30 AM

Welcome to the school on Pencil Code!
Introduction to the school. History and scientific summary of Pencil Code.

3. Introduce yourself

Alberto Roper Pol

10/20/25, 10:30 AM

Session to introduce yourself! We want to hear about your research interests, background and expectations from the school!

4. Basics of Pencil Code

Philippe Bourdin (University of Graz)

10/20/25, 11:30 AM

5. Practice session. Getting familiar with the code

Alberto Roper Pol

10/20/25, 3:00 PM

Installation and getting familiar with the code. Running your first sample(s).

Go on into the Pencil Code website (https://pencil-code.nordita.org/), download the code and install libraries (you can see the quick starter guide attached here) and documentation available on Pencil Code's website.

8. Practice session. Sound and Alfven waves

Alberto Roper Pol, Antonino Salvino Midiri (Universite de Geneve (CH)), Deepen Garg (University of Bonn)

10/20/25, 4:30 PM

9. Numerical schemes for differential equations

Antonino Salvino Midiri (Universite de Geneve (CH)), Philippe Bourdin (University of Graz)

10/21/25, 9:30 AM

31. Numerical schemes for differential equations

Philippe Bourdin (University of Graz)

10/21/25, 11:30 AM

11. Discrete Fourier transform. Power spectra

Isak Stomberg (IFIC Instituto de Física Corpuscular)

10/21/25, 12:30 PM

12. Post-processing and visualization

Axel Brandenburg (Nordita), Philippe Bourdin (University of Graz)

10/21/25, 2:00 PM

32. Post-processing and visualization

Philippe Bourdin (University of Graz), Simon Candelaresi (University of Augsburg)

10/21/25, 4:00 PM

13. Practice session. Forced helical turbulence

Alberto Roper Pol, Antonino Salvino Midiri (Universite de Geneve (CH)), Deepen Garg (University of Bonn)

10/21/25, 4:30 PM

10. Running on multiple CPUs. Parallelization

Matthias Rheinhardt (Aalto University)

10/22/25, 9:30 AM

7. Data handling and I/O approaches

Philippe Bourdin (University of Graz)

10/22/25, 10:30 AM

16. Contributing to the code. SVN and Github. Pencil Code autotests

Alberto Roper Pol

10/22/25, 11:30 AM

15. Accelerating Pencil Code on GPUs

Matthias Rheinhardt (Aalto University)

10/22/25, 12:00 PM

17. TH Colloquium: Dynamos versus magnetogenesis: astrophysics versus cosmology

Axel Brandenburg (Nordita)

10/22/25, 2:00 PM

Magnetic fields occur spontaneously both in astrophysics and in the early universe. Their energy sources are rather different: kinetic energy of the plasma in astrophysics and a variety of other forms of energy including axions, scalar fields, and chiral fermions in the cosmological settings. However, both areas have in common that the magnetic field is amplified by a long wavelength...

18. Free hands-on session. Projects definition

Alberto Roper Pol

10/22/25, 4:00 PM

19. Magnetohydrodynamics in the early Universe

Alberto Roper Pol

10/23/25, 9:30 AM

20. Primordial magnetic fields

Alberto Roper Pol, Axel Brandenburg

10/23/25, 11:30 AM

21. Chiral MHD

Deepen Garg (University of Bonn)

10/23/25, 12:30 PM

24. Gravitational waves

Chiara Caprini (CERN)

10/23/25, 2:00 PM

27. Inflation

Ramkishor Sharma (University of Hyderabad)

10/23/25, 4:00 PM

22. Practice session. Decaying MHD turbulence

Alberto Roper Pol, Antonino Salvino Midiri (Universite de Geneve (CH)), Deepen Garg (University of Bonn)

10/24/25, 9:30 AM

23. First-order phase transitions

Antonino Salvino Midiri (Universite de Geneve (CH)), Isak Stomberg (IFIC Instituto de Física Corpuscular)

10/24/25, 11:30 AM

25. Practice session. Gravitational waves

Alberto Roper Pol

10/24/25, 2:00 PM

26. CosmoGW

Alberto Roper Pol

10/24/25, 3:00 PM

28. Open practice session

Alberto Roper Pol

10/24/25, 4:00 PM

29. Concluding the school

Alberto Roper Pol

10/24/25, 5:30 PM

33. Introduction

Alberto Roper Pol, Axel Brandenburg, Philippe-André Bourdin

10/27/25, 10:00 AM

Reports from steering committee (P. Bourdin), scientific usage of Pencil Code (A. Brandenburg), Pencil Code school (A. Roper Pol)

34. Discussion session: coding sessions agenda setup

Alberto Roper Pol

10/27/25, 11:30 AM

Discussion of relevant topics to be addressed during the week, preparation of the agenda and distribution of the coding sessions.

35. Coding session: GPU accelerated code

Matthias Rheinhardt

10/27/25, 2:00 PM

Checking samples running with GPUs. Stable versions and future applications.

36. Coding session: Dark Matter applications

Axel Brandenburg

10/27/25, 4:00 PM

Dark Matter and N-body simulations with expansion. PIC simulations.

37. Diffusion and heat conduction in simulations of convection and solar atmosphere

Philippe-André Bourdin

10/28/25, 10:00 AM

43. Primordial magnetic field from chiral plasma instability with sourcing

Murman Gurgenidze

10/28/25, 10:30 AM

39. Discussion: documentation of Pencil Code

Illa Rivero Losada

10/28/25, 11:30 AM

40. Discussion: documentation (contd)

Alberto Roper Pol

10/28/25, 2:00 PM

41. Coding session: Python tools + MacOS tests + unique input file

Alberto Roper Pol

10/28/25, 4:00 PM

Part 1: python visualization, unifying Jupyter notebooks, extending documentation, GW turbulence postprocessing in Python, pip installation of Python packages.

Part 2: MacOS tests, docker.

Part 3: unique input file, restructuring the run directory.

42. The inverse magnetic cascade from radiation to matter domination

Axel Brandenburg (Nordita)

10/29/25, 10:00 AM

38. Using the Pencil Code to study Red giant stars

Carolina Ortiz Rodríguez

10/29/25, 10:30 AM

44. Discussion: distribution version control (Git and SVN), branches and breaking autotests

10/29/25, 11:30 AM

45. Relativistic magnetohydrodynamics in the early Universe

Antonino Salvino Midiri (Universite de Geneve (CH))

10/29/25, 3:30 PM

46. Coding session: Relativistic hydrodynamics and high frequency problem

Alberto Roper Pol

10/29/25, 4:15 PM

47. Coding session: AI applications for sub-grid modeling of non-linear physics + missing slices in Dardel

Matthias Rheinhardt

10/29/25, 5:30 PM

54. Discussion session: output of relevant papers for developments of Pencil Code when compiling the code

Axel Brandenburg (Nordita)

10/30/25, 10:00 AM

50. Discussion: Minimizing data load of huge simulations

Matthias Rheinhardt

10/30/25, 11:20 AM

51. Discussion session: coding standards

Philippe-André Bourdin

10/30/25, 11:50 AM

52. Coding session: reheating simulations and issue on gaussian noise initial conditions + scalar-induced GWs

10/30/25, 2:00 PM

Reheating simulations and issue on gaussian noise initial conditions for the logarithm of density.
Scalar-induced gravitational waves, studying scalar perturbations.

53. Coding session: Special modules + Initialization from external file

10/30/25, 4:00 PM

Dealing with multiple special modules: rename special by the name, fix the input list, rename variables.
Initialization of fields from an external file (e. g. with hdf5 external file).

48. Axion-USR model

Alireza Talebian Ashkezari

10/31/25, 10:00 AM

55. Discussion: Numerical Dissipation in the Pencil Code

Simon Candelaresi

10/31/25, 11:30 AM

56. Coding session: merging backreact_infl and klein_gordon modules + adding scalar/fluid coupling

10/31/25, 2:00 PM

57. PCUM25 closure

Alberto Roper Pol

10/31/25, 4:00 PM

14. Contributing to the code. SVN and Github

Alberto Roper Pol

49. Lattice simulation of axion-U(1) inflation

Ramkishor Sharma (University of Hyderabad)