mikroaaltotaustasäteily

Mikroaaltotaustasäteily, often abbreviated CMB (Cosmic Microwave Background), is electromagnetic radiation that fills the universe. It is a relic radiation from the early universe, specifically from a time when the universe was much hotter and denser. As the universe expanded and cooled, this radiation also cooled down to its current temperature of about 2.725 Kelvin.

The CMB was first predicted in 1940s by physicists George Gamow, Ralph Alpher, and Robert Herman as a consequence of the Big Bang theory. It was accidentally discovered in 1964 by Arno Penzias and Robert Wilson while they were working on a radio antenna. Their discovery provided strong evidence for the Big Bang model and is considered one of the most important cosmological observations.

The CMB is remarkably uniform in temperature across the entire sky, but there are tiny variations, or anisotropies, of about one part in 100,000. These subtle temperature fluctuations are crucial for understanding the universe's evolution. They represent the initial density variations in the early universe, which eventually grew under gravity to form the large-scale structures we observe today, such as galaxies and galaxy clusters.

Satellites like COBE (Cosmic Background Explorer), WMAP (Wilkinson Microwave Anisotropy Probe), and Planck have provided increasingly detailed maps of the CMB, allowing cosmologists to precisely measure fundamental cosmological parameters. These include the age of the universe, its composition (the proportions of dark matter, dark energy, and ordinary matter), and its expansion rate. The study of the CMB continues to be a cornerstone of modern cosmology.