| Part of a series of articles on the |
| mathematical constant π |
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| 3.1415926535897932384626433... |
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The ratio of any circle's circumference to its radius is a mathematical constant equal to two times the number pi (2π). This number has a value of approximately 6.2831853 and appears in many common formulas, often because it is the period of some very common functions — sine, cosine, eix, and others that involve trips around the unit circle. Some individuals have proposed giving this number its own symbol and using that instead of π in mathematics notation.[1][2] This proposition has been relayed in several news articles,[3][4][5] but has not been echoed in scientific publications nor by any scientific authority.
Advocacy
editIn an opinion column in The Mathematical Intelligencer, Robert Palais argued that π is "wrong" as a circle measure, and that a better value would be 2π, being the measure of the circle's circumference and the period of the sine, cosine, and complex exponential functions. He suggested a symbol like π but with three legs be used in place of 2π, demonstrating how it simplifies many mathematical formulas.[1]
In popular culture
editIn 2010, Michael Hartl posted an essay called The Tau Manifesto on his personal website. In it, he proposed using the Greek letter tau (τ) to represent that number instead. Hartl argued that an existing symbol like τ would face fewer barriers to adoption than a new symbol like the "three-legged pi" proposed in the Intelligencer.[6] A number of news outlets reported on "Tau Day", a holiday proposed in The Tau Manifesto' for June 28 to honour the number 2π.[3][7][8] The Royal Institution of Australia's Tau Day celebration in 2011 featured the performance of a musical work based on tau.[9]
According to the Massachusetts Institute of Technology's Dean of Admissions Stuart Schmill, "over [the] past year or so, there has been a bit of a debate in the math universe over which is a better number to use, whether it is Pi or Tau". Thus the school chose to inform 2012 applicants whether or not they were accepted on Pi Day at what MIT called Tau Time, 6:28 pm.[10]
See also
editReferences
edit- ^ a b Palais, Robert (2001). "π Is Wrong!" (PDF). The Mathematical Intelligencer. 23 (3): 7–8. Retrieved 2011-07-03.
- ^ Fattah, Geoffrey (4 July 2011). "University of Utah math professor starts international math movement". The Deseret News. Retrieved 2012-03-27.
- ^ a b Palmer, Jason (28 June 2011). "'Tau day' marked by opponents of maths constant pi". BBC News. Retrieved 2011-07-03.
- ^ "Your number's up: Why mathematicians are campaigning for pi to be replaced with alternate value tau". Mail Online. Associated Newspapers Ltd. June 29, 2011. Retrieved 2012-03-27.
- ^ Henderson, Mark (28 June 2011). "Maths mutineers say number's up for pi". The Australian Times. Retrieved 2012-03-27.
- ^ Hartl, Michael (28 June 2010). "The Tau Manifesto". Retrieved 2012-04-03.
- ^ "Tau: Is two pi better than one?". Today. BBC Radio 4. 28 June 2011. Retrieved 2012-03-27.
- ^ Black, Debra (28 June 2011). "Down with ugly pi, long live elegant Tau, physicist urges". The Toronto Star. Retrieved 2012-03-28.
- ^ "On National Tau Day, Pi Under Attack". Fox News Channel. NewsCore. June 28, 2011. Retrieved 2011-07-03.
- ^ Young, Colin A. "In nod to Pi Day, MIT releasing admissions decisions Wednesday evening". Boston Globe. Retrieved 17 March 2012.
External links
edit- Robert Dixon (Author) (18 June 2011). Pi ain't all that (flv) (YouTube).
- Vi Hart (Author) (14 March 2011). Pi Is (still) Wrong (flv) (YouTube).
- Salman Khan (11 July 2011). Tau versus Pi (flv) (YouTube). Khan Academy.
- OEIS: A019692 Decimal expansion of 2*Pi and related links at the On-Line Encyclopedia of Integer Sequences