The BBC South West region started on 20th April 1961 as part of the BBC Television Service, before becoming BBC One South West.

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The BBC South region started on 5th January 1961 as part of the BBC Television Service, before becoming BBC One South.

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The BBC East region started on 1st May 1959 as part of the BBC Television Service, before becoming BBC One East.

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The BBC North East & Cumbria region started in 1959 (tbc) as part of the BBC Television Service, before becoming BBC One North East & Cumbria.

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Formerly part of a wider BBC One South East region that included London and part of the South region. Separated from BBC One London 2001-09-03 following reorganisation of the South East region.

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The BBC West region started on 1st September 1957 as part of the BBC Television Service, before becoming BBC One West.

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

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Until 03/01/2009 BBC Two Wales (analogue) was known simply as BBC Two Wales. BBC Two Wales (digital) was BBC 2W. From 03/01/2009 BBC Two Wales schedules on both analogue and digital became identical

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Horizon: 2009-2010

Alan Davies

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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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