Ponente
Descripción
Despite its remarkable success, the standard cosmological model, $\Lambda$CDM, faces several serious challenges. Among them, the “Hubble tension”—the discrepancy between the value of the Hubble constant inferred from observations of the early Universe and that obtained directly from local measurements—is one of the most important problems in modern cosmology. As a possible solution to this tension, models in which the electron mass varies with time around the epoch of recombination have been proposed.
In this talk, I will provide an overview of how a time-varying electron mass modifies the recombination history and affects the sound-horizon scale, thereby potentially alleviating the Hubble tension. I will then present the observational constraint $\frac{m_e}{m_{e,0}} = 1.0101 \pm 0.0046$, obtained using the Markov Chain Monte Carlo code COBAYA from a combined analysis of the latest cosmic microwave background data from Planck, baryon acoustic oscillation data from DESI, and Type Ia supernova data from Pantheon+. Finally, I will discuss the physical implications of this result.
