A Chinese checkers board set up for a three player game.
Image: Chinese-checkers Wikimedia Commons user Splattne, CC BY-SA 3.0

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 modelsIn conversation with Jens Marklof
Bethany Clarke and Enric Solé-Farré chat to the professor and new president of the London Mathematical Society about academia, access and awardsCryptic wordsearch, Issue 19
Can you solve it?On the cover: skyrmions
Sven Bjarke Gudnason and Calum Ross introduce you to the wonderful world of skyrmionsSummer puzzles
Have a go at these puzzles, adequate for your holidays!Should you buy a Valentine’s day present?
For those of you tackling this dilemma, here's your answer...