Left: The large rectangle is plastic and can be split into a square (blue) and two plastic rectangles (red and {green).
Centre: The two arcs drawn in each square.
Right: A Harriss spiral.
Image: Chalkdust.
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On the cover: Hydrogen orbitals
Find out more about the weird shapes on the cover of Issue 08
Dear Dirichlet, Issue 05
Prof. Dirichlet tackles political arguments and werewolves in answering your personal problems
Roots: Pythagoras of Samos
Pythagoras gave us so much more than a² + b² = c²