Cosmological tensions in H0 and S8: current overview

Authors

DOI:

https://doi.org/10.47456/Cad.Astro.v7n1.51444

Keywords:

cosmological parameters, Hubble tension (H0), S8 tension, cosmological anomalies and tensions in ΛCDM

Abstract

The standard cosmological model has provided, for several decades, a consistent description of a wide range of cosmological and astrophysical observations. Despite this success, persistent discrepancies in the determination of fundamental parameters, in particular the Hubble constant (H0) and the amplitude of structure growth, commonly parametrized by S8, reveal significant tensions between probes of the early and late universe, with varying levels of statistical significance. These tensions may be partially associated with systematic uncertainties that are not yet fully understood, but they also motivate the investigation of extensions of ΛCDM, including modifications to dark energy, the dark sector, and gravity on large scales. In this didactic review, we present an overview of the main observations currently involved in these discrepancies, discuss their potential observational biases, and synthesize the most relevant theoretical scenarios, highlighting the prospects offered by current-generation cosmological surveys.

Author Biographies

  • Emanuelly Silva, Universidade Federal do Rio Grande do Sul

    Emanuelly Silva é doutoranda em Física pela UFRGS. Possui mestrado em Física pela mesma instituição e bacharelado em Física pela UFS. Atualmente pesquisa combinando abordagens teóricas, observacionais e computacionais, com ênfase na modelagem do espectro de potência da matéria em escalas não lineares. Além disso, estuda tensões cosmológicas, como H0 e S8, e modelos alternativos de energia escura, trabalhando com dados observacionais recentes, como os do DESI.

  • Miguel Sabogal, Universidade de Trento, Italia

    Miguel A. Sabogal é doutorando em Física pela Universidade de Trento, na Itália. Obteve o título de mestre em Física pela UFRGS. Sua pesquisa concentra-se na modelagem teórico-computacional da formação de estruturas em grande escala, em tensões cosmológicas, inferência bayesiana e métodos de aprendizado de máquina.

  • Rafael Nunes, Universidade Federal do Rio Grande do Sul

    Rafael C. Nunes é Professor Adjunto no Instituto de Física, Departamento de Astronomia da UFRGS. Atualmente, desenvolve pesquisas em diferentes áreas da Cosmologia e da Gravitação, com ênfase em modelagem teórico-computacional e observacional.

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Published

09-04-2026

Issue

Vol. 7 No. 1 (2026): Challenges to the Cosmological Standard Model

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Seção Temática

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Copyright (c) 2026 Emanuelly Silva, Miguel Sabogal, Rafael Nunes

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This work is licensed under a Creative Commons Attribution 4.0 International License.

How to Cite

[1]
E. Silva, M. Sabogal, and R. . Nunes, “Cosmological tensions in H0 and S8: current overview”, Cad. Astro., vol. 7, no. 1, p. 6–24, Apr. 2026, doi: 10.47456/Cad.Astro.v7n1.51444.