Exploring Sterile Neutrino Decays in the Adolescent Universe with Big Bang Nucleosynthesis and Large Scale Structure

The early universe provides an opportunity for researching and understanding neutrinos because in these dense and hot places, neutrinos are able to interact plenty with everything else in the universe. One issue in the current cosmological paradigm is the lithium problem, where there exists a discrepancy between predicted versus observed amounts of lithium during Big Bang Nucleosynthesis. We look beyond the Standard Model to try and address this discrepancy by using the early universe as a laboratory to study the decay of sterile neutrinos into Standard Model particles and its effect on cosmological observables. These decays create a nonthermal neutrino distribution as opposed to a nearly thermal distribution predicted by standard cosmology. This altered spectra affects the production of the primordial elements during BBN, and the formation of large scale structure. In this poster we discuss these effects and the resulting influence on the cosmological observables mentioned.