Implicit none

The first programming language I ever learned was Fortran. And before you ask, no, I’m not seventy years old. It just so happened that during my undergraduate degree, I took two courses on numerical methods for physics which were taught in Fortran, and for good reason: Fortran is still one of the best languages to…… Continue reading Implicit none

My first N months as a postdoc (where 0 < N < 12)

How long have I been a postdoc? It’s a little difficult to quantify. I finished my PhD thesis in December 2020, and submitted it in January 2021. I passed my viva in February 2021. I spent a few months climbing the walls waiting for my Spanish visa, and trying to do research at the same…… Continue reading My first N months as a postdoc (where 0 < N < 12)

Writing my PhD thesis

How do you write a PhD thesis? This question sounds like the start of the old joke: “How do you eat an elephant? One piece at a time”. A PhD thesis is a document which must explain, summarise and defend three or more years of research in your chosen field, often running to 40,000 words…… Continue reading Writing my PhD thesis

Thesis off-cuts: the reproducibility crisis in cosmology

As we frequently hear1, we’re now in the precision era of cosmology. What this really means is that we’re in the era of measuring things really well, and we’re getting really good at measuring things because we keep building ever more enormous and powerful telescopes. I remember attending the STFC Introductory Summer School on Astronomy…… Continue reading Thesis off-cuts: the reproducibility crisis in cosmology

Thesis off-cuts: how special is our place in the Universe?

Thanks to many hundreds of people making dedicated observations of the sky over many decades, we know that the majority of our Universe is comprised of two substances: dark matter and dark energy. Dark matter is an unknown type of matter, referred to as “dark” because it does not interact electromagnetically, meaning that it doesn’t…… Continue reading Thesis off-cuts: how special is our place in the Universe?

The distance duality relation

The distance duality relation tells us how, assuming that photons propagate on null geodesics in a pseudo-Riemannian spacetime and that their number is conserved, luminosity and angular diameter distances are related, via where dL is the luminosity distance, dA the angular diameter distance and z the redshift. This relation was introduced by Etherington in 1933,…… Continue reading The distance duality relation

Tribalism in science

Last week, a tweet by Roberto Trotta drew my attention to a recent paper by Simon Portegies Zwart that studied the amount of carbon dioxide emitted by running N-body simulations in different programming languages. https://twitter.com/R_Trotta/status/1309457430267523072 The figure that caught my attention was Figure 3, copied below from the version of the paper published in Nature…… Continue reading Tribalism in science

How asking a question on Stack Exchange kick started my career in research

I did my undergraduate degree at Aberystwyth University in Wales. I took the astrophysics course, which ran in parallel to the plain physics degree for the first two years, covering all the basics such as mathematical methods, classical mechanics, waves, optics, thermodynamics and so on. In the third year the astrophysics became the main focus,…… Continue reading How asking a question on Stack Exchange kick started my career in research