In Search of a Dynamical Dark Energy Equation of State
Abstract
Investigating the nature of dark energy in our universe is one of the main challenges of modern cosmology. This exotic source of stress-energy with negative pressure is responsible for the late cosmic acceleration but lacks a fundamental and well-defined theory. The simplest extension to the LambdaCDM model is offered by dynamical dark energy models in which the cosmic acceleration is driven by an evolving scalar field, dubbed quintessence, slowly rolling down a flat potential. Given their similarity in nature, there is a possibility that the inflation and quintessence fields are the same field, dominating the universe at different times. We describe an approach for unifying the two phases of accelerated expansions of the universe under one general evolving potential, consequently obtaining a general evolving dark energy equation of state. We use the Code for Anisotropies in the Microwave Background (CAMB) to analyze the effects of quintessence models with various forms of scalar field potentials. We particularly focus on "tracker" models such as the one with Raatra-Peebles potential. Results of the analysis include CMB anisotropy power spectra, and E- and B-mode polarizations. These are tested against 2018 Planck mission data to assess observability.
- Publication:
-
American Astronomical Society Meeting Abstracts #233
- Pub Date:
- January 2019
- Bibcode:
- 2019AAS...23335009K