Exploring Two-Field Inflation in the Wess-Zumino Model

Abstract

We explore inflation via the effective potential of the minimal Wess-Zumino model, considering both the real and imaginary components of the complex field. Using transport techniques, we calculate the full allowed range of $n_s$, $r$ and $f_{\mathrm{NL}}$ for different choices of the single free parameter, $v$, and present the probability distribution of these signatures given a simple choice for the prior distribution of initial conditions. Our work provides a case study of multi-field inflation in a simple but realistic setting, with important lessons that are likely to apply more generally. For example, we find that there are initial conditions consistent with observations of $n_s$ and $r$ for values of $v$ that would be excluded if only evolutions in the real field direction were to be considered, and that these may yield enhanced values of $f_{\mathrm{NL}}$. Moreover, we find that initial conditions fixed at high energy density, where the potential is close to quartic in form, can still lead to evolutions in a concave region of the potential during the observable number of e-folds, as preferred by present data. The Wess-Zumino model therefore provides an illustration that multi-field dynamics must be taken into account when seeking to understand fully the phenomenology of such models of inflation.

19 pages, 6 figures

References in corpus (8)

• Non-Gaussianities in two-field inflation
• Simple predictions from multifield inflationary models
• Inflationary perturbation theory is geometrical optics in phase space
• Moment transport equations for the primordial curvature perturbation
• Starobinsky-type Inflation in Dynamical Supergravity Breaking Scenarios
• Perturbative Reheating After Multiple-Field Inflation: The Impact on Primordial Observables
• Transport equations for the inflationary trispectrum
• Effects of the imaginary inflaton component in supergravity new inflation

Cited by in corpus (9)

• Calculations of Inflaton Decays and Reheating: with Applications to No-Scale Inflation Models
• Resurrecting Quadratic Inflation in No-Scale Supergravity in Light of BICEP2
• Phenomenological Aspects of No-Scale Inflation Models
• Two-Field Analysis of No-Scale Supergravity Inflation
• Inflation via Gravitino Condensation in Dynamically Broken Supergravity
• Hill crossing during preheating after hilltop inflation
• Affleck-Dine Sneutrino Inflation
• Resolving primordial physics through correlated signatures
• D-Flation