Nonminimal Couplings in the Early Universe: Multifield Models of Inflation and the Latest Observations
arXiv:1511.09148
Abstract
Models of cosmic inflation suggest that our universe underwent an early phase of accelerated expansion, driven by the dynamics of one or more scalar fields. Inflationary models make specific, quantitative predictions for several observable quantities, including particular patterns of temperature anistropies in the cosmic microwave background radiation. Realistic models of high-energy physics include many scalar fields at high energies. Moreover, we may expect these fields to have nonminimal couplings to the spacetime curvature. Such couplings are quite generic, arising as renormalization counterterms when quantizing scalar fields in curved spacetime. In this chapter I review recent research on a general class of multifield inflationary models with nonminimal couplings. Models in this class exhibit a strong attractor behavior: across a wide range of couplings and initial conditions, the fields evolve along a single-field trajectory for most of inflation. Across large regions of phase space and parameter space, therefore, models in this general class yield robust predictions for observable quantities that fall squarely within the "sweet spot" of recent observations.
17pp, 2 figs. References added to match the published version. Published in {\it At the Frontier of Spacetime: Scalar-Tensor Theory, Bell's Inequality, Mach's Principle, Exotic Smoothness}, ed. T. Asselmeyer-Maluga (Springer, 2016), pp. 41-57, in honor of Carl Brans's 80th birthday
References in corpus (11)
- The Standard Model Higgs boson as the inflaton
- Primordial Non-Gaussianities from Inflation Models
- Nonperturbative Dynamics Of Reheating After Inflation: A Review
- Perturbations in generalized multi-field inflation
- Conformal Transformations with Multiple Scalar Fields
- Cosmological Attractors and Initial Conditions for Inflation
- Primordial Bispectrum from Multifield Inflation with Nonminimal Couplings
- Preheating after Multifield Inflation with Nonminimal Couplings, I: Covariant Formalism and Attractor Behavior
- Multifield Dynamics of Higgs Inflation
- Primordial Perturbations from Multifield Inflation with Nonminimal Couplings
- Enhanced Preheating after Multi-Field Inflation: On the Importance of being Special