Pi explained

#1

Post by shawndumas » Fri, Jun 17, 2011, 7:36 PM UTC

Pi explained
upload.wikimedia.org

Re: Pi explained

#2

Post by hugh3 » Fri, Jun 17, 2011, 8:43 PM UTC

While I doubt this would actually explain pi to anyone who didn't already understand it, it is nonetheless kinda neat.

Re: Pi explained

#3

Post by mtinkerhess » Fri, Jun 17, 2011, 8:50 PM UTC

hugh3 wrote: post #2

While I doubt this would actually explain pi to anyone who didn't already understand it, it is nonetheless kinda neat.

It could help someone who's just learning about pi to grok it more easily.

Re: Pi explained

#4

Post by ctdonath » Fri, Jun 17, 2011, 8:51 PM UTC

How about some animations relating that to calculation of pi via assorted algorithms? esp. the "pick a digit" one?

Re: Pi explained

#5

Post by tokenadult » Fri, Jun 17, 2011, 9:10 PM UTC

"The Amazing Number π" by Peter Borwein,

http://www.nieuwarchief.nl/serie5/deel01/sep2000/pdf/borwein...

one of the leading researchers on π, has a history of investigation of the number and formulas for calculating π to increasingly accurate place-value approximations.

A very interesting secondary school textbook in English from Kerala, India

http://www.education.kerala.gov.in/englishmedium/mathseng/te...

shows the same visual representation of π on the number in section 3.1 of chapter 3.

Re: Pi explained

#6

Post by m_myers » Fri, Jun 17, 2011, 9:20 PM UTC

Next question: Is it possible for a piece of string to be pi units long? How do transcendental numbers translate to the real world?

Re: Pi explained

#7

Post by fexl » Fri, Jun 17, 2011, 9:25 PM UTC

m_myers wrote: post #6

Next question: Is it possible for a piece of string to be pi units long? How do transcendental numbers translate to the real world?

Just as difficult a question: Is it possible for piece of string to be 2 units long?

In the real world, you always run into limits on how finely you can measure things before you run into quandaries about number theory.

Re: Pi explained

#8

Post by phillmv » Fri, Jun 17, 2011, 9:26 PM UTC

m_myers wrote: post #6

Next question: Is it possible for a piece of string to be pi units long? How do transcendental numbers translate to the real world?

Sure. Take any circle made with a piece of string and declare it to be your reference unit circle.

Blammo! Its diameter is 1 and its length is now pi ;).

Re: Pi explained

#9

Post by benatkin » Fri, Jun 17, 2011, 9:30 PM UTC

Another diagram that gets the number for pi wrong: http://www.physicsforums.com/showthread.php?t=452917

Re: Pi explained

#10

Post by evanrmurphy » Fri, Jun 17, 2011, 9:38 PM UTC

An animation is worth a thousand incantations.