hash musings

February 19, 2008

I’ve been thinking about writing an essay about the beauty & weirdness of cryptographic hash functions. The way any digitized data, however huge, can be named by a short fixed-size binary string. The way there are in theory an infinite number of hash collisions, but in practice zero. I was talking to myself about it, this morning, and two quotes appeared, which I write down here to remember:

“Hashing is my favorite computer-science concept.”

and

“”SHA“:http://en.wikipedia.org/wiki/SHA_hash_functions is the Dewey Decimal code of ”Borges’s Universal Library“:http://en.wikipedia.org/wiki/The_Library_of_Babel.”

(except that there’s a fallacy in the second statement, which I leave as an exercise for the reader.)