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arXiv · 2605.10022

On the residual missing mass of the Bullet Cluster

Benoit Famaey
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Abstract

Modified Newtonian Dynamics (MOND) is a paradigm that can do away with dark matter at galaxy scales, but displays a residual missing mass discrepancy in galaxy clusters. Prompted by the updated JWST-based gravitational lens model of the Bullet Cluster, I confirm here that this cluster exhibits the same residual missing mass discrepancy as other clusters of similar mass in the MOND context. Moreover, this missing mass should be mostly collisionless, since it is centred on the galaxies of the Bullet Cluster.

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Benoit Famaey. 2026-05-11. On the residual missing mass of the Bullet Cluster. https://arxiv.org/abs/2605.10022

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