Cosmic voids are vast, nearly empty regions between galaxy filaments that hold clues to the universe’s structure and evolution. This guide explains how they form, their role in the cosmic web, and how they connect to the major epochs from the Big Bang to the present day.
The cosmic scale factor a(t) is a dimensionless parameter that tracks how distances in the universe grow with time. It connects redshift to expansion and underlies the standard model of cosmology, from the Planck epoch to the dark-energy era.
The baryon-to-photon ratio (η) is one of the most precisely measured numbers in cosmology, quantifying the tiny excess of matter over radiation in the early universe. It determines the abundances of light elements created during Big Bang nucleosynthesis and shapes the temperature fluctuations we observe in the cosmic microwave background, making it a cornerstone of the ΛCDM model.
The Big Bang did not occur at a single point in space; it happened everywhere at once. This article explores the origin and evolution of the universe, from the Planck epoch to the formation of stars and galaxies, and explains the evidence that supports the standard cosmological model.
The Big Bang was not an explosion in space but an expansion of space itself. This comprehensive guide explains the origin and evolution of the universe, from the Planck epoch to the formation of stars and galaxies, and clarifies why the common ‘explosion’ metaphor is misleading.
Explore the universe’s journey from the Planck epoch to the first stars and galaxies. This guide covers the major cosmic epochs, the cosmic microwave background, reionization, and the observatories that revealed them.
Big Bang Nucleosynthesis (BBN) is the process that forged the lightest atomic nuclei—deuterium, helium-3, helium-4, and lithium-7—during the first three minutes of cosmic history. This article explains the physics, the timeline, the observational evidence, and why BBN remains a cornerstone of the standard Big Bang model.
Explore the sequence of cosmic epochs that followed the Planck era—from the Grand Unification and inflation to recombination, the dark ages, and the formation of galaxies. This interactive guide explains the key physical processes, temperatures, and observations that define each stage of the universe’s evolution.
Explore the quark epoch—the fleeting first microsecond after the Big Bang when quarks and gluons roamed free—and trace the universe’s evolution through inflation, recombination, and the birth of stars and galaxies.
The Planck epoch is the earliest period in the history of the universe, lasting from t=0 to t=10^-43 seconds, when all four fundamental forces were unified and quantum gravity dominated. This article explores the Planck epoch and the subsequent cosmic epochs that shaped the universe we observe today.
