Conveners
Cosmology and Dark Energy: COS 1J
- Rachel Yohay (Florida State University (US))
- Kevin Huffenberger (Florida State University)
Cosmology and Dark Energy: COS 2J
- Sridhara Dasu (University of Wisconsin Madison (US))
- Alexander Joseph Wade (Florida State University (US))
- Barmak Shams Es Haghi (University of Utah)
Some of the open questions in fundamental physics can be addressed by looking at the distribution of matter in the Universe as a function of scale and time (or redshift). We can study the nature of dark energy, causing the accelerated expansion of the Universe. We can measure the sum of the neutrino masses, and potentially determine their hierarchy. We can test the standard model at energies...
The Dark Energy Spectroscopic Instrument (DESI) has embarked on an ambitious survey to explore the nature of dark energy with spectroscopic measurements of 35 million galaxies and quasars in just five years. DESI will determine precise redshifts and employ the Baryon Acoustic Oscillation method to measure distances from the local universe to beyond 11 billion light years, as well as employ...
The Dark Energy Spectroscopic Instrument (DESI) started its main survey. Over 5 years, it will measure the spectra and redshifts of about 35 millions galaxies and quasars over 14,000 square degrees. This 3D map will be used to reconstruct the expansion history of the universe up to z=3.5, and measure the growth rate of structure in the redshift range 0.7-1.6 with unequaled precision. The start...
An intriguing and well-motivated possibility for the particle makeup of the dark sector is that a small fraction of the observed abundance is made up of light, feebly-interacting particle species. Due to their weakness of interaction but comparatively large number abundance, cosmological datasets are particularly powerful tools to leverage here. In this talk I discuss the impact of these new...
Current measurements of Standard-Model parameters suggest that the electroweak vacuum is metastable. This metastability has important cosmological implications because large fluctuations in the Higgs field could trigger vacuum decay in the early universe. For the false vacuum to survive, interactions which stabilize the Higgs during inflation---e.g., inflaton-Higgs interactions or non-minimal...
I will present the Sejong Suite, an extensive collection of state-of-the-art high-resolution cosmological hydrodynamical simulations spanning a variety of cosmological and astrophysical parameters, primarily developed for modeling the Lyman-Alpha forest and the high-redshift cosmic web. Adopting a particle-based implementation, we follow the evolution of gas, dark matter (cold and warm),...
The axion is a well-motivated candidate for the inflaton, as the radiative corrections that spoil many single-field models are avoided by virtue of its shift symmetry. However, axions generically couple to gauge sectors. As the axion rolls through its potential, this coupling can result in the production of a co-evolving thermal bath, a situation known as "warm inflation." Inflationary...
We present a novel mechanism for baryogenesis via a low scale leptogenesis. The mechanism consists of two parts: first, out of equilibrium sub-weak-scale CP asymmetric decays of heavy sterile neutrinos result in leptogenesis carried by lighter sterile neutrinos. Second, the lepton asymmetry is transferred into a baryon asymmetry via baryon number violating scatterings of the light neutrino,...