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arXiv · 2511.03288

A Case for an Inhomogeneous Einstein-de Sitter Universe

Peter Raffai·Dominika E. R. Kis·Dávid A. Ködmön·Adrienn Pataki·Rebeka L. Böttger·Gergely Dálya
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Abstract

We present a local-to-global cosmological framework in which cosmic acceleration emerges from structure formation in an inhomogeneous Einstein-de Sitter (iEdS) universe, without dark energy. The model exhibits a quasilinear coasting evolution toward an effective Milne state driven by growing inhomogeneities. We test the iEdS model with ${H_0=72.5\ \mathrm{km\ s^{-1}\ Mpc^{-1}}}$ and ${\Omega_{\mathrm{m},0}=0.272}$ using CMB, BAO, and SN Ia data. The iEdS model fits the data comparably to $\Lambda$CDM and resolves the $H_0$ tension, while yielding a cosmic age ${t_0\simeq 13.67\ \mathrm{Gyr}}$ consistent with globular-cluster estimates.

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Peter Raffai, Dominika E. R. Kis, Dávid A. Ködmön, Adrienn Pataki, Rebeka L. Böttger, Gergely Dálya. 2025-11-05. A Case for an Inhomogeneous Einstein-de Sitter Universe. https://arxiv.org/abs/2511.03288

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