| From quasars to cosmic voids: new probes of dark energy with extreme cosmic structures |
| András Kovács |
| Konkoly Observatory, Budapest, Hungary |
| An over-arching goal of cosmology is a reconstruction of how minuscule density fluctuations seen in the cosmic microwave background (CMB) anisotropies grow to the intricate cosmic web. The consensus LCDM cosmological model has shown remarkable explanatory power over a variety of cosmic scales and epochs, and it narrates a reassuring story of a universe currently filled mostly with dark matter and dark energy. Yet, this explanation is not fully satisfactory, because the actual nature of the dark components remains a puzzle. In this presentation, I will provide an overview of the current developments and interesting tensions in cosmology, and what our group is hoping to achieve in the coming years. Supported by a Lendület grant, we develop new tools to comprehend the elusive dark energy component by using state-of-the-art galaxy and quasar survey data sets, probing the growth rate of structure in extreme environments near density peaks traced by powerful QSOs, as well as in dark and empty voids on 100 Mpc scales. The main goal of the planned 5-year program is to make decisive cross-correlation measurements of such super-structures and the CMB in un-probed, key redshift ranges, where the standard and alternative models of dark energy differ most significantly (z > 1). My groundwork results from the SDSS/BOSS, Pan-STARRS, and DES surveys put me in a strong position to now lead the planned new LSST-DESC, Euclid, J-PAS, and WEAVE-QSO analyses. With these novel probes of the cosmic web, we will determine whether some as-yet unknown physical effects or systematic biases complicate the picture in today's cosmology. Either way we will gather new knowledge about the Universe on the largest scales. |