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Re:Machine learning accelerates cosmological simulations by ghkbrew on Wednesday May 05, 2021 @11:46PM (#27058953)
I may have missed it while skimming the article, but I saw no mention of how accurate the ML model was.

It may look like the results of a high fidelity simulation, but how useful is that?

Re:Machine learning accelerates cosmological simulations by vegetablepotpie on Thursday May 06, 2021 @12:05AM (#27059070)
I feel skeptical as well.

> We couldn't get it to work for two years," Li said, "and suddenly it started working. We got beautiful results that matched what we expected.

How many times have you gotten an algorithm to work, where later you realize you had an off by 1 error, or a double free somewhere in your code that you didn’t catch until you exposed your program to more situations?

I am curious about how they validated the ML approach. The advantage of simulation is the ability to uncover emergent phenomena that are difficult to predict and are not expected. It could be that they’re averaging a lot of common situations and they may miss novel outcomes.

Re:Machine learning accelerates cosmological simulations by 256lie on Thursday May 06, 2021 @12:20AM (#27059143)
They mention a GAN which is a generative model and currently no good measure of evaluation (beside metrics like Fréchet inception distance).

The article only mentions a qualitative comparison but no incorporation of causal / physic based-modeling that I would imagine would be important in astronomy.

Easy enough for GAN to synthesize realistic, high-resolution images without any underlying model of reality / casuality.