“School of Physics”

Back to Papers Home
Back to Papers of School of Physics

Paper   IPM / P / 17108
School of Physics
  Title:   Cascading Dark Energy
1.  K. Rezazadeh
2.  A. Ashoorioon
3.  D. Grin
  Status:   Preprint
  Year:  2022
  Supported by:  IPM
The standard cosmological model is in the midst of a stress test, thanks to the tension between supernovae-based measurements of the Hubble constant H0 and inferences of its values from Cosmic Microwave Background (CMB) anisotropies. Numerous explanations for the present-day cosmic acceleration require the presence of a new fundamental scalar field, as do Early Dark Energy (EDE) solutions to the Hubble tension. This raises the possibility that \textit{multiple} fields cooperatively contribute to the dark energy component in bursts throughout cosmic time due to distinct initial conditions and couplings. Here, this Cascading Dark Energy (CDE) scenario is illustrated through a realization that effectively reduces to a two-field model, with two epochs in which dark energy is cosmologically significant. The model is compared to measurements of the CMB, baryon acoustic oscillations, and observations of Type-Ia supernovae. It is found that this scenario ameliorates the Hubble tension, improving over purely late-time models of dark energy, and improves agreement between the related Rock `n' Roll EDE scenario and galaxy survey measurements of baryon acoustic oscillations.

Download TeX format
back to top
scroll left or right