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Re: Monte Carlo Hits Again



A Geiger Tube can be an excellent generator of random digits.
For example, consider equal time intervals for which total
numbers of background counts fluctuate around 100 (practically
never less than 50 or more than 150). By collecting last digits
only you will have a sample of random integers between 0 and 9.

Count from a radioactive source producing, on the average
10000 counts per time interval. By collecting only last three digits
you will have a sample of random integers between 0 and 999.
Combine such sequences to produce random numbers between
0 and 999999. Etc. etc.

Pseudo-random numbers generated by computers always repeat
themselves, sooner or later. The trick is to produce sequences
which are long enough to finish Monte Carlo simulations before
the ends of looping sequences. I think that a Geiger counter (or
a noise generator) connected to a computer would be a good
randomizer of pseudo-random sequences. (For example, by
injecting a new seed after every ten million pseudo-random
numbers.) I remember reading that stand-alone generators of
true random numbers were actually used by researchers before
computers became available.
Ludwik Kowalski