# PBS Infinite Series

• ### The Assassin Puzzle | Infinite Series

84,559 views 1 year ago
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Imagine you have a square-shaped 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?

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Solution to the Assassin Puzzle:
www.math3ma.com/mathema/2018/5/17/is-the-square-a-secure-polygon

Previous Episode:
Instant Insanity Puzzle

Let’s walk through this puzzle a little more precisely. First, instead of thinking of a physical room with actual people inside, I really want you to think of a square in the xy plane. Pick any two points in the square, and let’s call one of those points A for “assassin,” and the other point T for “target.” Now a “shot” from the assassin is really just a ray emanating out of the point A which can, like a ball on a billiard table, bounce back and forth between the sides of the square. But unlike an actual game of pool, let’s assume the trajectory has constant speed and that it can bounce back and forth for forever!

Written and Hosted by Tai-Danae Bradley
Produced by Eric Brown
Graphics by Matt Rankin
Assistant Editing and Sound Design by Mike Petrow and Linda Huang

Special thanks to Roman Pinchuk for supporting us on our Converse level on Patreon.

Along with thanks to Matthew O'Connor, Yana Chernobilsky, and John Hoffman who are supporting us on Patreon at the Identity level!

And thanks to Mauricio Pacheco and Andrew Poelstra who are supporting us at the Lemma level! Show less
• ## An Infinite Playlist Play all

• ### The End of An Infinite Series - Duration: 2 minutes, 32 seconds.

• 101,534 views
• 1 year ago
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• ### The Assassin Puzzle | Infinite Series - Duration: 9 minutes, 13 seconds.

• 84,559 views
• 1 year ago
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• ### Instant Insanity Puzzle | Infinite Series - Duration: 10 minutes.

• 48,236 views
• 1 year ago
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• ### Defining Infinity | Infinite Series - Duration: 11 minutes.

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• ### Unraveling DNA with Rational Tangles | Infinite Series - Duration: 10 minutes.

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• ### How Big are All Infinities Combined? (Cantor's Paradox) | Infinite Series - Duration: 15 minutes.

• 91,882 views
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• ### The Geometry of SET | Infinite Series - Duration: 11 minutes.

• 40,700 views
• 1 year ago
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• ### What was Fermat’s “Marvelous" Proof? | Infinite Series - Duration: 14 minutes.

• 77,707 views
• 1 year ago
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• ### What are Numbers Made of? | Infinite Series - Duration: 14 minutes.

• 70,248 views
• 1 year ago
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• ## Quantum Computers Play all

• ### The Mathematics of Quantum Computers | Infinite Series - Duration: 12 minutes.

• 2 years ago
• 470,997 views
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What is the math behind quantum computers? And why are quantum computers so...
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• ### How to Break Cryptography | Infinite Series - Duration: 15 minutes.

• 2 years ago
• 199,187 views
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Only 4 steps stand between you and the secrets hidden behind RSA cryptograp...
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• ### Hacking at Quantum Speed with Shor's Algorithm | Infinite Series - Duration: 16 minutes.

• 2 years ago
• 189,603 views
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Classical computers struggle to crack modern encryption. But quantum comput...
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• ## Higher Dimensions Play all

• ### A Breakthrough in Higher Dimensional Spheres | Infinite Series | PBS Digital Studios - Duration: 7 minutes, 52 seconds.

• 830,975 views
• 2 years ago
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• ### Dissecting Hypercubes with Pascal's Triangle | Infinite Series - Duration: 14 minutes.

• 94,429 views
• 2 years ago
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• ### The Honeycombs of 4-Dimensional Bees ft. Joe Hanson | Infinite Series - Duration: 11 minutes.

• 239,880 views
• 2 years ago
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• ### Higher-Dimensional Tic-Tac-Toe | Infinite Series - Duration: 12 minutes.

• 119,424 views
• 1 year ago
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• ## Probability Play all

• ### Can a Chess Piece Explain Markov Chains? | Infinite Series - Duration: 13 minutes.

• 144,416 views
• 2 years ago
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• ### What is a Random Walk? | Infinite Series - Duration: 12 minutes.

• 156,744 views
• 2 years ago
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• ### Making Probability Mathematical | Infinite Series - Duration: 14 minutes.

• 110,107 views
• 2 years ago
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• ### Stochastic Supertasks | Infinite Series - Duration: 11 minutes.

• 85,797 views
• 2 years ago
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• ### How to Generate Pseudorandom Numbers | Infinite Series - Duration: 14 minutes.

• 130,968 views
• 1 year ago
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• ## Graph Theory Play all

• ### Solving the Wolverine Problem with Graph Coloring | Infinite Series - Duration: 13 minutes.

• 85,276 views
• 2 years ago
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• ### Network Mathematics and Rival Factions | Infinite Series - Duration: 12 minutes.

• 80,602 views
• 2 years ago
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• ### The Cops and Robbers Theorem | Infinite Series - Duration: 9 minutes, 58 seconds.

• 97,980 views
• 1 year ago
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• ### How Many Cops to Catch a Robber? | Infinite Series - Duration: 9 minutes, 46 seconds.

• 66,887 views
• 1 year ago
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• ### Instant Insanity Puzzle | Infinite Series - Duration: 10 minutes.

• 48,236 views
• 1 year ago
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