ELFT HÍRADÓ

[vidakris AT konkoly.hu]

Szemináriumi meghívó / Invitation to a seminar
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CSFK CSI SZEMINÁRIUM / KONKOLY OBSERVATORY SEMINAR

Date: Apr 27, 2023 (Thursday) 14:00


András Kovács (Konkoly Observatory, Budapest, Hungary):
From quasars to cosmic voids: new probes of dark energy with extreme cosmic 
structures


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 LendĂĽlet 
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.

The seminar will be held live in the Detre hall with audience, but also 
streamed online via Zoom. If you are unable to attend the presentation in 
person, you can join us via this link
https://us06web.zoom.us/j/82806911982?pwd=SVZpT0syQ1J6dHBvSkF4N2dXNEQ0dz09
or the meeting ID: 828 0691 1982 and passcode: 206265



Everyone is welcome!

Krisztián Vida, Ramon Brasser
organizers
https://konkoly.hu/szeminar/szeminarium.shtml