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BBC One is a TV channel that started broadcasting on the 20th April 1964. It replaced BBC Television.

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Horizon tells amazing science stories and reveals worlds you've never seen before.

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Horizon: 2009-2010

Alan Davies

Marcus du Sautoy

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Horizon: 2009-2010: Episode 6: How Long is a Piece of String?

How Long is a Piece of String?

Episode 6

Episode 6: How Long is a Piece of String?

2009-2010

BBC Two - Horizon, 2009-2010, How Long is a Piece of String?

Alan Davies attempts to answer the proverbial question: how long is a piece of string?

Alan Davies tries to answer the proverbial question: how long is a piece of string? But the task soon turns into a mind-bending voyage of discovery where nothing is as it seems.

Alan Davies attempts to answer the proverbial question: how long is a piece of string? But what appears to be a simple task soon turns into a mind-bending voyage of discovery where nothing is as it seems.

An encounter with leading mathematician Marcus du Sautoy reveals that Alan's short length of string may in fact be infinitely long. When Alan attempts to measure his string at the atomic scale, events take an even stranger turn. Not only do objects appear in many places at once, but reality itself seems to be an illusion. 

Ultimately, Alan finds that measuring his piece of string could - in theory at least - create a black hole, bringing about the end of the world.

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2009-2010

Episode 6: How Long is a Piece of String?

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