117 karma · joined May 3, 2025
[1] https://hsm.stackexchange.com/questions/7751/did-einstein-sa...
While the work the authors do is important, in no sense does the tool they produced actually run a simulation.
A simulation implies a physical model and usually partial differential equations that are often solved on supercomputers, but here the neural network is rather interpolating some fixed simulation output in a purely data-driven way.
The simulations have not gotten faster due to neural networks, cosmologists have just gotten better at using them. Which is great!
Edit: see the sub-comment in the thread by crazygringo for the lead author’s take
A good faith reading of your comment leads me to guess you might take issue with a small number of unrelated NSF CAREER awards going to research you don’t find worthwhile (such as those alluded to in your link). But the vast majority of CAREER awards fund what I would imagine you would consider “real science” [1], like the content of OP.
So please do not tune out!
[1] You can count them here in the list of all CAREER awards: https://www.nsf.gov/awardsearch/advancedSearchResult?PIId=&P...
This research is also supported by Chinese funding agencies, who I imagine will not be engaging such senseless hamstringing of their national scientific organs…
[1] https://www.science.org/doi/10.1126/sciadv.adr6202
[2] See page 5 of https://www.energy.gov/sites/default/files/2025-07/doe-fy-20...
[3] See page “Facilities - 5” of https://nsf-gov-resources.nsf.gov/files/00-NSF-FY26-CJ-Entir...
[4] See page “Summary Tables - 1” of the link in [3].
It is far from clear that the Chinese government supports this type of open data sharing.
From a quick glance, the authors look only at a small (relative to the overall size of the universe) region of space and study the emission from the gas between galaxies (specifically, the WHIM [2]). It would seem challenging to draw major conclusions based on this study - and the authors themselves conclude higher quality data of the type they are using is needed.
Some context:
This missing gas or "missing baryons" problem is a very old one [3]. See here [4] for a nice review (Section 4 mentions the missing baryons problem, which really is localized to the cosmologically "recent" universe - we know where the gas was when the universe was older.) It increasingly seems like the missing baryons problem can be resolved by gas living in the WHIM between galaxies. This recent paper [5] argues using Fast Radio Burst data that, in principle, this problem can be solved this way.
[1] https://arxiv.org/pdf/2506.14917
[2] The charmingly named "Warm-hot intergalactic medium" - https://arxiv.org/pdf/astro-ph/0007217
[3] "Baryons" is cosmology jargon for ordinary matter - gas and plasma.