Hitting the Jackpot: The Birth of the Monte Carlo Method (2023)

And of course the Nick Metropolis mentioned in this story is the first author of Metropolis, Rosenbluth, Rosenbluth, Teller, and Teller (1953), which went a step farther and introduced MCMC. See just above equation 4 of (https://bayes.wustl.edu/Manual/EquationOfState.pdf).

Farther down, below equation (6), we see the understatement:

“The above argument, of course, does not specify how rapidly the canonical distribution is reached.”

on which about 7 decades of further research would be done!

> there are around 8 × 1067 ways to sort a deck of cards (a number approaching the estimated number of atoms in the observable universe

They surely mean 8x10^67

In my opinion this article obfuscates more than it clarifies.

The story of the atomic bomb and the H-bomb will, for the foreseeable future, have classified details. LANL is one of the national labs, the one where the initial research on the atomic bomb was built, and some people there know the classified bits, but of course they won't write a story for the public.

Ulam work on both bombs. But his name is more often associated with the H-bomb, he is considered one of its 2 fathers (the other being Teller, as in the "Ulam-Teller" design [1]).

So, was the Monte-Carlo method that he invented used for the H-bomb, or for the atomic bomb? After you read this blog post you have no idea.

I think the reason is that the Monte Carlo method that Ulam discovered was used for atomic bombs, but not for the Hiroshima and Nagasaki ones. It was used for the post war designs. The non-sexy truth is that the Monte Carlo method was not needed at all for the development of the A-bomb. And we don't know if it was needed at all for the H-bomb, because that stuff is classified.

Why this article then?

I think it's because LANL felt the need to honor Ulam somehow. Ulam was definitely an immense genius, one in the same class as Fermi, Bethe and Teller. But conveying exactly how he was a genius means you go into classified details. So, we end up with this vague generic praise. Too bad.

[1] https://en.wikipedia.org/wiki/History_of_the_Teller%E2%80%93...

Link is 404, archive.org to the rescue:

https://web.archive.org/web/20240320213112/https://discover....

"In 1944, while at a railway station he started chatting with a stranger who turned out to be an engineer who worked on ENIAC." I thought this was precisely the kind of careless talk people were told to avoid during wartime.