As we build up light rays, the shape of the envelope begins to emerge. The only difference between this diagram and the physical system is that here, the overlap makes a dark envelope, whereas in the cup the overlap makes a bright envelope
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Read Issue 15 now!
Squid Game, hidden harmonies and DnD coming your way in our brand new issue! Plus all your favourite puzzles & columns.
In conversation with Sammie Buzzard
Ellen talks to the mathematician and scientist about Attenborough, arctan and Antarctica
Prize crossnumber, Issue 15
Win a £100 Maths Gear goody bag by solving our infamous puzzle
Surviving the bridge in Squid Game
E Adrian Henle, Nick Gantzler, François-Xavier Coudert & Cory Simon team up for a deadly challenge
Dear Dirichlet, Issue 15
Weddings, holidays and catfish find their way into the prof's postbox this issue.
Accidentally mathematical songs
Goran Newsum always should be someone you really love