Astronomy Seminar Series
Ludovic Van Waerbeke, University of British Columbia
Let's assume dark matter is a particle. The DM theories currently tested, WIMPs-like, either via direct or indirect detection, cover only a tiny range of the allowed DM parameters space, and have not been particularly successful so far. A new DM candidate, the Axion Quark Nugget (AQN), has been proposed by Zhitnitsky in 2003, partly inspired by the quark nuggets (Witten 1984). In the AQN model, DM particles are very massive (gram mass or more) and interact very rarely, but very strongly, with the baryonic sector. They behave as cold dark matter, but they can induce various electromagnetic signals under certain conditions, without violating nucleosynthesis or any known Big Bang fundamental constraints.
In this talk I will review the basic properties of the model and discuss some of our ongoing research projects at UBC in order to test the model. This requires a very interdisciplinary approach, by looking at how AQNs interact with planets, stellar atmospheres, compact objects, and up to the largest cosmological scales. This makes AQN a highly testable DM model, with potential for direct detection, unlike most currently popular WIMPs alternatives.
Ludovic Van Waerbeke is professor in the Physics and Astronomy Department at the University of British Columbia and a Senior Fellow of the Canadian Institute for Advanced Research in the Cosmology and Gravity Program. The study of the universe is stumbling upon two mysteries: it is made of 5% of normal matter, 20% of an unknown type of matter, dark matter and for 75% of a puzzling form of energy, dark energy. Normal matter can be seen with traditional observational techniques that capture light at all possible wavelength with all kinds of telescopes. Dark matter can be detected indirectly with the gravitational lensing effect. The effect of dark energy can only be measured on the expansion rate of the Universe. Using a combination of observations of normal and dark matter and dark energy, Ludovic’s research is a quest for a better understanding of the Universe and its fundamental laws, the large scale structures, galaxy clusters and galaxy formation.