Saturday 08 March 2025
A novel approach to resolving the Hubble tension, a longstanding conundrum in cosmology, has been proposed by a team of researchers. The solution involves introducing multiple axion-like fields to modify the expansion history of the universe at both early and late times.
The Hubble tension refers to the discrepancy between measurements of the Hubble constant, which describes the rate at which the universe is expanding, from observations of the cosmic microwave background (CMB) and those obtained from local distance-ladder methods. The former suggests a value of around 67 kilometers per second per megaparsec, while the latter indicate a value closer to 73 kilometers per second per megaparsec.
To address this tension, researchers have explored various extensions to the standard model of cosmology, known as Lambda-Cold Dark Matter (Lambda-CDM). These modifications often involve introducing new fields or altering the properties of existing ones. In this case, the authors propose a multi-field approach, where multiple axion-like fields interact with each other and the standard model particles.
Axions are hypothetical particles that were first proposed to solve a long-standing problem in the Standard Model of particle physics, known as the strong CP problem. They have since been considered as dark matter candidates, and their properties make them an attractive solution for modifying the expansion history of the universe.
The authors’ approach is based on the idea that these axion-like fields can interact with each other and the standard model particles in a way that modifies the expansion history of the universe at both early and late times. This allows them to address both the Hubble tension and the discrepancy between the predictions from Lambda-CDM and observations of large-scale structure.
The authors’ solution involves introducing three axion-like fields, each with its own set of properties. The first field is responsible for modifying the expansion history at very early times, while the second and third fields are involved in the late-time modifications. By adjusting the properties of these fields, the authors are able to reproduce the observed values of the Hubble constant from both CMB and local distance-ladder methods.
The proposed solution also passes several other tests, including consistency with observations of baryon acoustic oscillations (BAO) and the sound horizon at recombination. This suggests that the multi-field axion-like model is a viable alternative to Lambda-CDM, which has been the dominant paradigm in cosmology for decades.
Cite this article: “Resolving the Hubble Tension with Multi-Axion Fields”, The Science Archive, 2025.
Here Are The Keywords: Hubble Tension, Axion-Like Fields, Lambda-Cdm, Cosmology, Expansion History, Cosmic Microwave Background, Dark Matter, Particle Physics, Strong Cp Problem, Baryon Acoustic Oscillations.
