Powered by Indico v3.0.3
The nature of dark matter and dark energy remains one of the most profound mysteries in modern cosmology. In addition to these theoretical challenges, recent cosmological observations have revealed potential signs of new physics beyond the standard ΛCDM paradigm. In this talk, I will begin by briefly reviewing current cosmological tensions, including the latest DESI evidence for dynamical dark energy, the Hubble tension, and the S8 tension. I will then explore possible new physics underlying these tensions, with a particular focus on interactions between dark matter and dark energy. I will demonstrate that a simple coupling between the two components can simultaneously address two distinct anomalies: the DESI-indicated dynamical dark energy and the S8 tension. We propose a stable and technically natural particle physics realization of this idea, which exhibits an apparent phantom crossing behavior in the dark energy equation of state, consistent with DESI findings. The possible resolutions to the Hubble tension will also be discussed.
Biography: Dr. Meng-Xiang Lin is currently a Postdoctoral Fellow at the Center for Particle Cosmology at the University of Pennsylvania. Prior to joining Penn, he completed his undergraduate studies at Peking University and earned his Ph.D. from the University of Chicago. His research interests span a broad range of topics in theoretical cosmology, with a particular focus on uncovering possible new physics behind current cosmological tensions and using gravitational waves as a probe of fundamental physics. More information can be found on his personal website: https://m-x-lin.github.io/index.html
Prof. Jia Liu