"The cosmic microwave background (CMB, CMBR) is microwave radiation that fills all space in the observable universe."
The afterglow of the Big Bang, which is the most direct evidence for its occurrence and provides insight into the early conditions of the Universe.
The Big Bang Theory: This is the prevailing cosmological model that describes the origin and evolution of the universe.
Cosmic Inflation: This is a theory that explains the rapid expansion of the universe in its first moments after the Big Bang.
Photon Decoupling: This refers to the point in time when the universe became transparent, allowing photons to travel freely through space and create a background radiation.
Primordial Nucleosynthesis: This is the process of creating light elements, such as hydrogen and helium, during the early stages of the universe.
Cosmic Microwave Background Radiation: This refers to the electromagnetic radiation that permeates the entire universe and is believed to be left over from the Big Bang.
Temperature Fluctuations: These are small, random changes in the temperature of the cosmic microwave background that reveal information about the structure and evolution of the universe.
Dark Matter: This is an invisible form of matter that is believed to make up a large portion of the universe and influence the formation of cosmic structures.
Dark Energy: This is a mysterious force that is causing the expansion of the universe to accelerate, and its properties are still not well understood.
Wilkinson Microwave Anisotropy Probe (WMAP): This was a space-based observatory that mapped the cosmic microwave background and provided important data for cosmologists.
Planck Satellite: This was another space-based observatory that studied the cosmic microwave background with high precision and provided even more detailed data.
Inflation Models: These are theoretical models that attempt to explain the mechanisms behind cosmic inflation and the resulting cosmic microwave background radiation.
Baryon Acoustic Oscillations: These are subtle patterns in the distribution of matter in the universe that can be used to measure its expansion rate and other cosmological parameters.
Weak Gravitational Lensing: This is a technique that uses the bending of light by cosmic structures to map the distribution of matter in the universe.
Large Scale Structure: This refers to the overall distribution of galaxies, clusters, and other cosmic structures on the largest scales.
Dark Matter Halos: These are clumps of dark matter that are believed to be the seeds of galaxy formation.
Cosmic Shear: This is a distortion in the shapes of distant galaxies caused by the gravitational lensing effect of intervening matter.
Power Spectrum: This is a mathematical tool used to quantify the distribution of energy at different wavelengths in the cosmic microwave background radiation.
Reionization: This is a process by which the first stars and galaxies ionized the hydrogen gas in intergalactic space, ending the cosmic dark ages.
Cosmic Variance: This is a statistical uncertainty in cosmological measurements that arises from the fact that we have only one universe to observe.
Standard Cosmological Model: This is the current best-fit model that describes the evolution of the universe based on a combination of observations and theoretical predictions.
"A sufficiently sensitive radio telescope detects a faint background glow that is almost uniform and is not associated with any star, galaxy, or other object."
"The accidental discovery of the CMB in 1965 by American radio astronomers Arno Penzias and Robert Wilson was the culmination of work initiated in the 1940s."
"CMB is landmark evidence of the Big Bang theory for the origin of the universe."
"In the Big Bang cosmological models, during the earliest periods, the universe was filled with an opaque fog of dense, hot plasma of sub-atomic particles."
"As the universe expanded, this plasma cooled to the point where protons and electrons combined to form neutral atoms of mostly hydrogen."
"Known as the recombination epoch, this decoupling event released photons to travel freely through space – sometimes referred to as relic radiation."
"However, the photons have grown less energetic due to the cosmological redshift associated with the expansion of the universe."
"The surface of last scattering refers to a shell at the right distance in space so photons are now received that were originally emitted at the time of decoupling."
"The CMB is not completely smooth and uniform, showing a faint anisotropy that can be mapped by sensitive detectors."
"The anisotropy structure is determined by various interactions of matter and photons up to the point of decoupling."
"The distribution of the anisotropy across the sky has frequency components that can be represented by a power spectrum displaying a sequence of peaks and valleys."
"The peak values of this spectrum hold important information about the physical properties of the early universe."
"The first peak determines the overall curvature of the universe."
"The second peak details the density of normal matter."
"The third peak details the density of so-called dark matter."
"Extracting fine details from the CMB data can be challenging, since the emission has undergone modification by foreground features such as galaxy clusters."
"With a standard optical telescope, the background space between stars and galaxies is almost completely dark."
"This glow is strongest in the microwave region of the radio spectrum."
"The accidental discovery of the CMB in 1965 by American radio astronomers Arno Penzias and Robert Wilson was the culmination of work initiated in the 1940s."