1. in HPC

    About our PRACE project GRaSPT

    I created this report after wrapping up our large high performance computing project about strong early universe phase transitions. It doesn't seem to be available anywhere publicly, so I am putting it online here.


  2. in Code

    Faster numerical integration in SciPy

    I was keen to help a colleague accelerate their numerical integrations, while keeping the project as high-level and pythonic as possible. This article (and the associated GitLab repository) is the result of my constructing a minimal working example to do numerical integration in SciPy with the integrand specified in a compiled Cython function.


  3. in Writing

    Kumpula Campus Code of Conduct

    I wrote an article for Arkhimedes on the new Kumpula Campus Code of Conduct. Here is a copy of the article as submitted. Corrections and alterations made after submission are not reflected here.


  4. in Presentations

    UKCosmo Presentation, May 2019

    I gave a blackboard talk at UKCosmo in May 2019. As I usually like to present movies and other visualisations when giving talks, I have collected that material (and key references and acknowledgments) here instead. The scanned notes for the talk are now available, and the final movies from the …


  5. in Code

    A small trick to distributed paper writing with [pdf]latex and git

    With most of my collaborators, we use git for version control of draft papers, written in latex. I usually bundle a makefile in the git repo to check for unresolved references and rerun [pdf]latex if necessary. In this post I will discuss how to use low-level git commands to embed useful information into the generated PDF.


  6. in Posters

    Cosmic necklaces poster

    I gave a poster on cosmic necklaces at COSMO-15 in Warsaw, as well as the subsequent DiRAC Science Day. This page has links to the original posters and other information.


  7. in Code

    PySpark for HPC: some success but a work in progress

    Recently, I published the paper Revisiting the envelope approximation: gravitational waves from bubble collisions. This work compares two methods for computing the gravitational wave power spectrum from colliding bubbles from a phase transition in the early universe. It turned out to be an ideal example of a physics simulation in which the MapReduce algorithm can be applied.