Episodes

The Assassin Puzzle
S2 E19  9m 12s
Imagine you have a squareshaped room, and inside there is an assassin and a target. And suppose that any shot that the assassin takes can ricochet off the walls of the room, just like a ball on a billiard table. Is it possible to position a finite number of security guards inside the square so that they block every possible shot from the assassin to the target?

Instant Insanity Puzzle
S2 E18  9m 32s
Imagine you have four cubes, whose faces are colored red, blue, yellow, and green. Can you stack these cubes so that each color appears exactly once on each of the four sides of the stack?

Defining Infinity
S2 E17  10m 31s
Set theory is supposed to be a foundation of all of mathematics. How does it handle infinity?

Unraveling DNA with Rational Tangles
S2 E16  9m 36s
When you think about math, what do you think of? Numbers? Equations? Patterns maybe? How about… knots? As in, actual tangles and knots?

How Big are All Infinities Combined? (Cantor's Paradox)
S2 E15  13m 2s
Infinities come in different sizes. There’s a whole tower of progressively larger "sizes of infinity". So what’s the right way to describe the size of the whole tower?

The Geometry of SET
S2 E14  10m 21s
In the card game SET, what is the maximum number of cards you can deal that might not contain a SET?

What was Fermat’s “Marvelous" Proof?
S2 E13  10m 50s
If Fermat had a little more room in his margin, what proof would he have written there?

What are Numbers Made of?
S2 E12  10m 7s
In the physical world, many seemingly basic things turn out to be built from even more basic things. Molecules are made of atoms, atoms are made of protons, neutrons, and electrons. So what are numbers made of?

What Does It Mean to Be a Number? (The Peano Axioms)
S2 E11  9m 35s
If you needed to tell someone what numbers are and how they work, without using the notion of number in your answer, could you do it?

Telling Time on a Torus
S2 E10  7m 17s
What shape do you most associate with a standard analog clock? Your reflex answer might be a circle, but a more natural answer is actually a torus. Surprised? Then stick around.

How to Divide by "Zero"
S2 E9  8m 1s
What happens when you divide things that aren’t numbers?

Beyond the Golden Ratio
S2 E8  8m 57s
You know the Golden Ratio, but what is the Silver Ratio?
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