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arXiv · 2311.05217

Super-Resolution Emulation of Large Cosmological Fields with a 3D Conditional Diffusion Model

Adam Rouhiainen·Michael Gira·Moritz Münchmeyer·Kangwook Lee·Gary Shiu
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Abstract

High-resolution (HR) simulations in cosmology, in particular when including baryons, can take millions of CPU hours. On the other hand, low-resolution (LR) dark matter simulations of the same cosmological volume use minimal computing resources. We develop a denoising diffusion super-resolution emulator for large cosmological simulation volumes. Our approach is based on the image-to-image Palette diffusion model, which we modify to 3 dimensions. Our super-resolution emulator is trained to perform outpainting, and can thus upgrade very large cosmological volumes from LR to HR using an iterative outpainting procedure. As an application, we generate a simulation box with 8 times the volume of the Illustris TNG300 training data, constructed with over 9000 outpainting iterations, and quantify its accuracy using various summary statistics.

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Adam Rouhiainen, Michael Gira, Moritz Münchmeyer, Kangwook Lee, Gary Shiu. 2023-11-09. Super-Resolution Emulation of Large Cosmological Fields with a 3D Conditional Diffusion Model. https://arxiv.org/abs/2311.05217

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