Conformal time is a coordinate that factors out cosmic expansion, letting light travel in straight lines on a comoving grid. It underlies the particle horizon and provides a natural timeline for the universe’s major epochs, from the Planck era to structure formation.
Baryogenesis is the hypothesized process that created the observed excess of matter over antimatter in the early universe. This article explains the problem, Sakharov’s conditions, candidate mechanisms, and the cosmic timeline from the Planck epoch to structure formation.
The cosmic Dark Ages were a period after recombination when the universe was filled with neutral hydrogen and no stars had yet formed. This article explores this pivotal epoch and the full timeline of cosmic evolution, from the Planck epoch to the present day.
Cosmic inflation, the exponential expansion of the universe in its first fraction of a second, is predicted to have generated a background of primordial gravitational waves. Detecting these ripples in spacetime would provide direct evidence for inflation and reveal physics at energies far beyond particle accelerators, connecting quantum mechanics with gravity.
The dipole anisotropy is the largest temperature variation in the cosmic microwave background, a ~3.36 mK pattern caused by our motion relative to the CMB rest frame. It reveals the velocity of the Local Group and provides a crucial reference for cosmological measurements.
A comprehensive guide to the horizon problem, why the cosmic microwave background is so uniform, and how cosmic inflation resolves this paradox, with a timeline of cosmic epochs.
Gravitational lensing of the cosmic microwave background (CMB) subtly distorts its polarization, converting E-modes into B-modes and contaminating the primordial signal from inflation. This article explains the physics, the cosmic epochs that shaped the CMB, and how modern experiments disentangle the lensing signal to probe the early universe.
CMB polarization is the faint directional pattern imprinted on the oldest light in the universe by Thomson scattering at the last scattering surface. It encodes information about inflation, gravitational waves, and the structure of the early cosmos, offering one of the most powerful observational windows into the universe’s first moments.
Symmetry breaking in the early universe describes how the unified forces of nature separated as the cosmos cooled, shaping the particles and structure we observe today. This article explores the key epochs from the Planck era to structure formation, the role of inflation, and the cosmic microwave background as a relic of that transformative time.
The cosmic microwave background’s acoustic peaks encode the geometry and matter content of the universe. By measuring their positions and heights, cosmologists can determine the total density, baryon density, and curvature with remarkable precision.
