Cosmic inflation

Cosmic inflation is a hypothesized period of extremely rapid expansion in the early universe, proposed to explain its large-scale uniformity and near-flat geometry.

Inflaton: A hypothetical field whose potential energy drives cosmic inflation in many inflationary models. Its dynamics are the proposed source of the accelerated expansion.
Big Bang: The hot, dense early state from which the observable universe expanded and evolved. Inflation is proposed as an early episode within the universe's broader expansion history.
Alan Guth: American theoretical physicist who introduced the original inflationary-universe scenario in 1981. His proposal made rapid early expansion a solution to cosmological puzzles.
Primordial gravitational waves: Gravitational waves generated in the early universe, including a possible inflationary background. A detected primordial background could test inflation's energy scale and models.
Cosmic microwave background: Relic radiation released about 380,000 years after the Big Bang, now observed across the sky. Its temperature patterns preserve evidence of primordial fluctuations stretched during inflation.
Cosmological principle: The assumption that the universe is statistically homogeneous and isotropic on sufficiently large scales. Inflation offers a possible physical account of the large-scale uniformity this principle describes.
Alexei Starobinsky: Soviet and Russian physicist whose 1980 model described an early phase of accelerated cosmic expansion. His model independently anticipated inflation through corrections to Einstein gravity.
B-mode polarization: A curl-like pattern in the polarization of cosmic microwave background radiation. Inflationary gravitational waves could imprint a characteristic large-scale B-mode signal.
Primordial perturbations: Early variations in density and curvature that seeded the later growth of cosmic structure. Inflation can amplify quantum fluctuations into these initial variations.
Friedmann equations: Equations of general relativity governing the expansion of a homogeneous, isotropic universe. They provide the framework for describing accelerated expansion in cosmology.

Linked from 51 pages