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arXiv · 2603.04784

Accelerating massive galaxy formation with primordial black hole seed nuclei

Jeremy Mould
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Abstract

If massive primordial black holes (PBHs) exist and constitute a fraction of the dark matter, they can dramatically catalyze galaxy formation. By acting as pre-existing, high-density seeds, they can shorten the galaxy assembly time to as little as 100 Myr for up to 10^8 solar mass PBH seeds, allowing for the rapid formation of host halos. Furthermore, low surface brightness or diffuse galaxies may represent a natural outcome of this process, perhaps as the residue of halos seeded by smaller PBHs that failed to accrete a major baryonic component.

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Jeremy Mould. 2026-03-05. Accelerating massive galaxy formation with primordial black hole seed nuclei. https://arxiv.org/abs/2603.04784

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