Equation-of-State Parameter for Reheating
By Julian B. Muñoz, M. Kamionkowski. 2014
163 citations recorded by the source corpus.
Constraints to the parameters of inflation models are often derived assuming some plausible range for the number--e.g., $N_k=46$ to $N_k=60$--of $e$-folds of inflation that occurred between the time that our current observable Universe exited the horizon and the end of inflation. However, that number is, for any specific inflaton potential, related to an effective equation-of-state parameter $w_{\mathrm{re}}$ and temperature $T_{\mathrm{re}}$, for reheating. Although the physics of reheating is highly uncertain, there is a finite range of reasonable values for $w_{\mathrm{re}}$. Here we show that by restricting $w_{\mathrm{re}}$ to this range, more stringent constraints to inflation-model parameters can be derived than those obtained from the usual procedure. To do so, we focus in this work in particular on natural inflation and inflation with a Higgs-like potential, and on power law models as limiting cases of those. As one example, we show that the lower limit to the tensor-to-scalar ratio $r$, derived from current measurements of the scalar spectral index, is about 20%-25% higher (depending on the model) with this procedure than with the usual approach.
Subfields: Astronomy and Astrophysics, Nuclear and High Energy Physics
View Paper: https://www.semanticscholar.org/paper/462ce9b1b2bc312053ab1f90a5b46d2ebbac14a2
How researchers see this paper
The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.
In Astronomy and Astrophysics
In Nuclear and High Energy Physics
Citations in the corpus
- Dynamically induced Planck scale and inflation (2015, background): “In figure 2 we plot the inflaton mass as a function of ξS for both negative-field and positive-field inflation (the two regions are partially overlapping) for 50 < N < 60 [83–85].”
- The Quest for B Modes from Inflationary Gravitational Waves (2015, methodology): “Inflation with a Higgs-like potential, V (φ) ∝ (φ2 − v2)2, where v is a parameter (Kaplan & Weiner 2004), requires r ∼> 0.03 for 1 − ns ∼ 0.05 (Munoz & Kamionkowski 2015).”
- Reheating predictions in single field inflation (2015, result): “While completing the first version of this work, it was brought to our attention that a similar approach was carried out by [99].”