News & Events
Meng-Xiang Lin (Simon Fraser University)
Event Details
McDonald Institute Seminar Series
Location: Queen's: STI 501 / YouTube
Date: May 26, 2026
Time: 2:30pm - 3:30pm
Dr. Meng-Xiang Lin is a CITA National Fellow at Simon Fraser University.
Cosmological Tensions as Clues to New Paradigms in the Dark Sector
Abstract:
The nature of dark matter and dark energy remains one of the most profound mysteries in modern physics. In addition to these longstanding theoretical challenges, recent cosmological observations have revealed potential signs of new physics beyond the standard LCDM paradigm. In this talk, I will begin with a brief overview of current cosmological tensions, including the latest DESI evidence for dynamical dark energy and the longstanding Hubble tension. I will then discuss possible new physics underlying these anomalies, focusing in particular on interactions between dark matter and dark energy.
I will present a stable and technically natural particle-physics realization of this scenario through interactions between dark baryons and dark axions. The model exhibits an apparent phantom-crossing behavior in the dark energy equation of state, consistent with the latest DESI observations, while also offering a possible resolution to the Hubble tension. Fits to current cosmological datasets show evidence for nonzero interactions in the dark sector.
The McDonald Institute seminar will be held in Stirling 501 and streamed live to the McDonald Institute YouTube channel.
A Zoom link is also available and shared via email by the organizers. Please reach out to admin@mcdonaldinstitute.ca for access.