Calum is a lecturer in physics at Edge Hill University where he studies topological solitons and enjoys talking about maths and physics to anyone who will listen. He can often be found on the side of a mountain or out on a bike, talking to himself about solitons.
More from Chalkdust

Oπnions: In defence of toy models
Calum gets on his soap box about toy models
Cryptic wordsearch, Issue 19
Can you solve it?
On the cover: skyrmions
Sven Bjarke Gudnason and Calum Ross introduce you to the wonderful world of skyrmions
Headscratchers
We review the eighth of this year's nominees for Book of the Year
Primes à la Euler
Infinitely many primes ending in 1, 3, 7 and 9 proved in typically Eulerian style.
Dear Dirichlet, Issue 01
Moonlighting agony uncle Professor Dirichlet answers our readers' personal problems.
