How do I count thee? Let me count the ways?

Sheldon Cooper's favorite number

      If you are a fan of the television series "The Big Bang Theory", then you know Sheldon often wears a shirt with 73 ...

Showing posts with label normal number. Show all posts
Showing posts with label normal number. Show all posts

Wednesday, February 27, 2013

Mr. Finch and pi

March 14, Pi Day, is coming up. Is there any more to be said about π that hasn’t been said?



In the January 3, 2013 episode of the TV show “Person of Interest” (“you are being watched ... ”), computer genius Mr. Finch says that since π is an infinite non-repeating decimal, “contained within this string of decimals is every single other number. Your birth date, combination to your locker, your social security number ...”

Really? I didn’t think that is necessarily so. Mr. Finch doesn’t explain why.

There is a site that lets you search for a specific string of digits within the first 200 million digits of π, http://www.angio.net/pi/piquery, but of course just because your number doesn’t appear, doesn’t prove anything. 200 million is a long way from infinity.

Are the digits in π truly random? There is something called a normal number, which is a real number whose infinite sequence of digits is distributed uniformly. See http://en.wikipedia.org/wiki/Normal_number which says it is believed that π is normal, but this has not been proven.

So we think Mr. Fitch was right, but we’re not 100% sure.