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
Carnival of mathematics 152
We round up some of the last month's top mathematical posts from around the internet
Review of The Maths Behind by Colin Beveridge
Should you ask Santa for 'Ice Col' Beveridge's encyclopedic tome this festive period?
The mathematics of Maryam Mirzakhani
We take a proper look at her mathematical accomplishments
