Baryogenesis is the process that generated the observed imbalance between matter and antimatter in the early universe. This article explains the Sakharov conditions, leading scenarios such as electroweak baryogenesis and leptogenesis, and traces the cosmic epochs from the Planck era to recombination.
Primordial black holes are hypothetical black holes that formed in the first moments after the Big Bang, before stars and galaxies existed. They could explain dark matter and offer a unique window into the universe’s earliest epochs, from the Planck era to recombination.
Redshift surveys map the three-dimensional distribution of galaxies by measuring their redshifts, revealing the large-scale structure of the cosmos and providing critical evidence for dark matter, dark energy, and the sequence of cosmic epochs from the Big Bang to the present.
The BICEP/Keck experiment is a series of South Pole telescopes searching for the faint polarization pattern in the cosmic microwave background that would signal primordial gravitational waves from cosmic inflation. While no direct detection has been made as of 2025, the experiment has set the tightest constraints yet on inflation models.
Gravitational lensing of the cosmic microwave background (CMB) is the bending of CMB photons by massive structures along their path, distorting the temperature and polarization patterns we observe. This subtle effect provides a powerful probe of dark matter distribution, cosmic structure growth, and fundamental cosmology.
Grand Unified Theories (GUTs) propose that the strong, weak, and electromagnetic forces were once a single unified interaction in the earliest moments of the universe. This article explores the physics of GUTs, the Grand Unification Epoch, and the full cosmic timeline from the Planck epoch to structure formation.
The COBE mission measured the cosmic microwave background with unprecedented precision, confirming its blackbody spectrum and detecting tiny temperature fluctuations that seeded galaxy formation. These results solidified the Big Bang model and earned the 2006 Nobel Prize in Physics.
The Epoch of Reionization marks the last major phase transition of the universe, when neutral hydrogen was ionized by the first stars and galaxies. Its redshift—around 6 to 10—reveals when cosmic dawn occurred and how the intergalactic medium evolved.
The Friedmann–Lemaître–Robertson–Walker (FLRW) metric is the exact solution of Einstein’s field equations that describes a homogeneous, isotropic expanding universe. It underpins the ΛCDM concordance model, providing the framework for cosmic epochs, the cosmic microwave background, and the large-scale structure we observe today.
The Sachs–Wolfe effect explains how gravitational potential wells and hills imprint large-scale temperature fluctuations on the cosmic microwave background. It connects the first fraction of a second after the Big Bang to the dark-energy-dominated present, offering a key test of inflation and the standard cosmological model.
