Cutting a möbius loop in half is fun. Sticking two möbius loops together and cutting them both in half is romantic.

Much more on möbius loops and topology in my book Things to Make and Do in the Fourth Dimension:
http://mathsgear.co.uk/collections/bo...

Also on Maths Gear is the Cos I Love You card:
http://mathsgear.co.uk/products/cosi...

Think Maths parametric heart coordinates resources:
http://thinkmaths.co.uk/downloads/pa...

And here is my Royal Institution lecture:
   • Four Dimensional Maths: Things to See...  

MATT PARKER: Standup Mathematician
Website: http://standupmaths.com/

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