Artist's rendering of potentially habitable exoplanets. Image credit: NASA/JPL-Caltech/R. Hurt (SSC-Caltech)

Physics Colloquium with Tansu Daylan on Dark Matter and Exoplanets

Tansu Daylan (Hosted by Krawczynski) from the Kavli Institute for Astrophysics and Space Research, MIT, will be presenting the colloquium "A Compute-Intensive Exploration and Characterization of Our Celestial Wonders: Dark Matter and Exoplanets"

Our species has been contemplating the celestial sphere for millennia and achieved numerous observational and theoretical breakthroughs toward a unified and self-consistent description of the physical cosmos. At the cosmological scales, we witness extensive and compelling evidence for dark matter whose apparent absence of non-gravitational interactions remains an intriguing puzzle. Meanwhile closer to home, we discover and characterize planets beyond our solar system, which contextualize life and our planet Earth as well as yielding appealing targets for biosignature and technosignature searches. In this talk, I will highlight my excitement for and contributions to these comprehensive investigations. I will show how the particle nature of dark matter can be indirectly revealed by using multiple messengers such as high-energy photons and cosmic rays. Furthermore, I will illustrate a powerful probe of dark matter substructure at sub-galactic scales using strong gravitational lensing, in order to test the Lambda Cold Dark Matter (LCDM) model and accurately measure the expansion of the Universe. Regarding exoplanets, I will highlight the striking diversity of the observed exoplanet population, which raises exciting questions as to why our solar system does not contain super-Earths and sub-Neptunes and motivate us to refine our models of planet formation, evolution, and migration. Toward this purpose, the Transiting Exoplanet Survey Satellite (TESS) has been surveying the sky for small exoplanets that will be opportune cosmic laboratories for controlled and comparative transmission spectroscopy with JWST, such as the recent discovery of the TOI 1233 multiplanetary system with a nearby, bright, and Sun-like host star. Furthermore, atmospheric characterization of exoplanets probe their complex space weather, climate, and photochemistry. Along with manifestations of stellar magnetism such as starspots and flares, these atmospheric conditions will reveal the habitability of terrestrial exoplanets. On a related note, I will argue that, unlike in the past, our contemporary signals in astronomy are buried in petabytes of time-series, imaging, or spectroscopic data, requiring fast and massively-parallelized algorithms and optimized hardware to sift through or model the data. Therefore, robust hypothesis testing via transdimensional Bayesian inference and efficient exploitation of machine learning constructs such as convolutional and adversarial neural networks become crucial for reaching outstanding research breakthroughs. Thus, I will discuss how I look forward to discovering rare systems and seek answers to fundamental questions in cosmology and exoplanets by exploiting high performance computing on near-future astrometric and photometric time-domain data sets from new Gaia and the Rubin Observatory.

 

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