Inflation after WMAP3

TL;DR

The paper reviews the status of inflationary cosmology after WMAP3, confirming basic predictions, discussing untested predictions like gravitational waves, and highlighting future experimental prospects.

Contribution

It provides an updated assessment of inflationary predictions in light of WMAP3 data, emphasizing potential future tests of gravitational waves and deviations from scale invariance.

Findings

Basic inflation predictions are supported by WMAP3 data.

Current data disfavors a perfectly scale-invariant spectrum.

Future experiments could detect primordial gravitational waves with tensor/scalar ratio around 0.01.

Abstract

I discuss the current status of inflationary cosmology in light of the recent WMAP 3-year data release. The basic predictions of inflation are all supported by the data. Inflation also makes predictions which have not been well tested by current data but can be by future experiments, most notably a deviation from a scale-invariant power spectrum and the production of primordial gravitational waves. A scale-invariant spectrum is disfavored by current data, but not conclusively. Tensor modes are currently poorly constrained, and slow-roll inflation does not make an unambiguous prediction of the expected amplitude of primordial gravitational waves. A tensor/scalar ratio of $r \simeq 0.01$ is within reach of near-future measurements.