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arXiv · 2609.38303

A Strong Cosmologically Coupled Mass Growth Solution in Linearized General Relativity

Kevin S. Croker·Joshua Cohon·Viktor T. Toth·Massimiliano Rinaldi·Nicolas Fernandez·Joel L. Weiner·Duncan Farrah·Gregory Tarlé·Gustavo Niz·Christopher Cain·James W. Rohlf·Alejandro Aviles·Jake Summers·Leander Thiele·Rogier A. Windhorst·Joshua Grumski-Flores
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Abstract

DESI Data Release 2 has heightened interest in cosmologically coupled black holes (CCBHs) as an explanation for accelerating late-time expansion, but known models for CCBHs grow too slowly to drive it. We construct at linear order a solution to General Relativity whose Hernandez-Misner-Sharp mass passively grows $\propto a^κ$ as the universe expands. The constant $κ$ enters all eigenvalues of the Weyl and stress-tensor operators, so growth is unambiguously physical in both free-field and material sectors. The solution is causal over spacetime relevant for stellar collapse compact objects. A cloud of energized vacuum emerges at $κ= 3$, complementing the $a^3$ scaling predicted elsewhere for the masses of energized vacuum black holes. This first step toward $κ\sim 3$ CCBH exact solutions enables observational tests with pulsar binaries.

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Kevin S. Croker, Joshua Cohon, Viktor T. Toth, Massimiliano Rinaldi, Nicolas Fernandez, Joel L. Weiner, Duncan Farrah, Gregory Tarlé, Gustavo Niz, Christopher Cain, James W. Rohlf, Alejandro Aviles, Jake Summers, Leander Thiele, Rogier A. Windhorst, Joshua Grumski-Flores. 2026-09-29. A Strong Cosmologically Coupled Mass Growth Solution in Linearized General Relativity. https://arxiv.org/abs/2609.38303

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