GemesAS · HackerTrans

9 месяцев назадdiscuss

Prior to the current administration there's been a ratcheting up of political influence / social engineering on science grants as well. The last DoE Office of Science grant I applied to had a DEI requirement that was also used during screening. My preference would all this political influence be dialed down.

GemesAS

2 года назадdiscuss

Someone by the name of V. Minakhin. They have an irrational hatred of Bayesian statistics. He blocked me on twitter for pointing out his claim about significant companies do not use Bayesian methods is contradicted by the fact that I work for one of those companies and use Bayesian methods.

GemesAS

2 года назадdiscuss

Modern weapon codes couple computationally heavy physics like radiation & neutron transport, hydrodynamics, plasma, and chemical physics. While a 1-D or 2-D simulation might not be too heavy in compute often large ensembles of simulations are done for UQ or sensitivity analysis in design work.

GemesAS

2 года назадdiscuss

A little known bit of history is Feynman developed a diagrammatic method for expressing the moments of PGFs in his study of the stochastic theory of fission chains. This was before his work on QED. See:

https://www.osti.gov/biblio/1775045

GemesAS

2 года назадdiscuss

I'm interested in environmental policy and dipped into reading the degrowth literature. IMO the review is correct, much of the academic degrowth literature is very weak--the field is more an activist movement rather than a scholarly one.

It's funny to think of applying degrowth to past environmental problems. Let's imagine it's 1900 and we are concerned about the sustainability of whale hunting, would degrowing the world's economy be the right approach then? Maybe that is too extreme, what about ozone depletion 50 years ago? Would strangling economic development & technological innovation back then lead to a desirable future?

GemesAS

2 года назадdiscuss

I think part of it was there a number of subsequent experiments that would also confirmed Lee & Yang's prediction in short order.

My PhD advisor worked with Wu at Columbia. He held her in very high esteem.

GemesAS

2 года назадdiscuss

The US isn't producing HEU anymore but still has a decent sized stockpile of it.

A number of the pits in the active stockpile are actually composite Pu/HEU pits & you can actually use HEU in implosion weapons as well.

GemesAS

2 года назадdiscuss

Pit production is likely the rate limiting factor.

We disassembled a bunch of AFAPs so have a lot of weapons grade plutonium around. But Pu is nasty to work with & Rocky Flats--the previous pit production facility--closed down years ago. Pit production moved to Los Alamos but it is at a much reduced capability.

Also, Pantex--where nuclear weapons are assembled--isn't exactly the model for speed & efficiency.

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