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arXiv · 2510.08573

Reconstructing the local density field with combined convolutional and point cloud architecture

Baptiste Barthe-Gold·Nhat-Minh Nguyen·Leander Thiele
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Abstract

We construct a neural network to perform regression on the local dark-matter density field given line-of-sight peculiar velocities of dark-matter halos, biased tracers of the dark matter field. Our architecture combines a convolutional U-Net with a point-cloud DeepSets. This combination enables efficient use of small-scale information and improves reconstruction quality relative to a U-Net-only approach. Specifically, our hybrid network recovers both clustering amplitudes and phases better than the U-Net on small scales.

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Baptiste Barthe-Gold, Nhat-Minh Nguyen, Leander Thiele. 2025-10-09. Reconstructing the local density field with combined convolutional and point cloud architecture. https://arxiv.org/abs/2510.08573

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