The baryonic Tully-Fisher relation as an independent direct probe of cosmology and of the nature of dark matter
Year: 2026
Type: article
Abstract: Context. The baryonic Tully-Fisher relation (BTFR), a well-established galaxy scaling relation that links the dynamical mass of rotation-supported galaxies through their maximum circular velocity to the baryonic luminous mass, has emerged over the decades as a fundamental scaling relation and a robust calibrated distance indicator. It provides a robust benchmark to test galaxy formation and evolution theories as well as an independent probe of the expansion of the Universe. Aims. In this Letter, we show for the first time that the BTFR is also simultaneously directly sensitive to the cosmological parameters Ω m and σ 8 , the astrophysical feedback from supernovae (SNe) and active galactic nuclei (AGNs), and the mass of dark matter particles ( M wdm ) and can therefore be used as novel, direct probe of cosmology and fundamental physics. Methods. We performed simulation-based inference on the large DREAMS cosmological magneto-hydrodynamic simulations suite and trained deep neural networks in the form of normalizing flows to estimate the posterior distributions of Ω m , σ 8 , M wdm , and the three astrophysical free parameters, given a BTFR measurement. Results. Our framework is able to recover unbiased values for Ω m and σ 8 with sub-percent deviation accuracy and a ∼2.6% and ∼3.9% median precision, respectively, and can therefore capture the warm dark matter particle mass ( M wdm ) with a ∼30 − 35% precision, as well as constrain the SN feedback parameters (but not the one regulating AGN feedback). Conclusions. We conclude that, beyond its usage as a distance indicator and for constraining the baryon cycle and the feedback mechanisms that shape galaxy formation and evolution, the BTFR constitutes a direct independent probe of cosmology and fundamental physics. It opens new promising avenues, such as constraining the cosmic growth rate and testing gravity theories, to be explored with the future Square Kilometer Array.
Source: Astronomy and Astrophysics
Author: Francesco Sinigaglia
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $1,865
OpenAlex ID: W7164824783