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Puzzles

Illustration: black, numbered cats crossing a calendar. An extra "13" lurks in the background.
insights puzzle

Is It Friday the 13th Again?

How our society defines years, months and weeks can seem frustratingly arbitrary. Can you bring order to our unruly calendar?

Still illustration: changing genes
insights puzzle

Solution: ‘A Ticking Evolutionary Clock’

How to calculate when a gene’s rate of evolution will slow to a crawl.

GIF illustration: changing genes
insights puzzle

A Ticking Evolutionary Clock

How quickly will a gene’s rate of evolution slow to a crawl?

Illustration: balloon modelling as a metaphor for entanglement
insights puzzle

Solution: ‘Taming Quantum Weirdness’

A simple analogue could offer insights into one of the most astonishing results of quantum mechanics.

Illustration: balloon modelling as a metaphor for entanglement
insights puzzle

How to Tame Quantum Weirdness

Can balloon animals help blunt uneasy feelings about “spooky action at a distance”?

Illustration: bucket half-full of amoebas.
insights puzzle

Solution: ‘How Many Half-Lives?’

When do negative results from a half-life experiment mean a theory is dead?

Illustration: bucket half-full of amoebas.
insights puzzle

How Many Half-Lives Do You Have?

Gaining an intuition about half-life requires some unintuitive thinking.

insights puzzle

Solution: ‘Hanging Far Out Over the Edge’

A simple and elegant way to stack identical flat objects so that they project over an edge as far as possible.

insights puzzle

How to Hang Far Out Over the Edge

What formula describes the farthest you can stack flat blocks over the edge of a table to form a seemingly gravity-defying half-bridge to nowhere?