Pólya’s Urn


Life seems to take sly pleasure in magnifying the effects of chance.  A spot of bad luck in your love-life can leave you embittered and wary, making you less romantically attractive.  If a delayed paycheck makes a check you wrote bounce, you’ll instantly get charged overdraft fees, plus penalties if your balance can’t cover the fees.  On the up side, if you’re slightly taller than the other kids in your gym class, you may get more playing time on the basketball court and become the best player, even if by the end of the year your height has regressed to the mean. Life is full of things like this, but we often lose sight of that truth.  We say “You win a few, you lose a few”, as if in the long run things are bound to even out.  In life, it’s often “You win a few, so you’re likelier…

View original post 4,515 more words


Feynman on Fermat’s Last Theorem by Luis Batalha

Feynman on Fermat’s Last Theorem by Luis Batalha

“While reading more about Feynman’s derivation of the Schrödinger equation in Schweber’s book QED and the Men who made it I ended up finding a mention to an undated two-page manuscript written by Feynman about Fermat’s Last Theorem. The manuscript doesn’t appear in the book but Schweber casts some light on Feynman’s approach which I will try to explain here in more detail.”