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arXiv · 2210.12907

Super-resolution simulation of the Fuzzy Dark Matter cosmological model

Meris Sipp·Patrick LaChance·Rupert Croft·Yueying Ni·Tiziana Di Matteo
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Abstract

AI super-resolution, combining deep learning and N-body simulations has been shown to successfully reproduce the large scale structure and halo abundances in the Lambda Cold Dark Matter cosmological model. Here, we extend its use to models with a different dark matter content, in this case Fuzzy Dark Matter (FDM), in the approximation that the difference is encoded in the initial power spectrum. We focus on redshift z = 2, with simulations that model smaller scales and lower masses, the latter by two orders of magnitude, than has been done in previous AI super-resolution work. We find that the super-resolution technique can reproduce the power spectrum and halo mass function to within a few percent of full high resolution calculations. We also find that halo artifacts, caused by spurious numerical fragmentation of filaments, are equally present in the super-resolution outputs. Although we have not trained the super-resolution algorithm using full quantum pressure FDM simulations, the fact that it performs well at the relevant length and mass scales means that it has promise as technique which could avoid the very high computational cost of the latter, in some contexts. We conclude that AI super-resolution can become a useful tool to extend the range of dark matter models covered in mock catalogs.

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Meris Sipp, Patrick LaChance, Rupert Croft, Yueying Ni, Tiziana Di Matteo. 2022-10-24. Super-resolution simulation of the Fuzzy Dark Matter cosmological model. https://doi.org/10.1093/mnras%2Fstad2341

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