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The cosmic microwave background was first predicted in 1948 by Ralph Alpher and Robert Herman, in a correction [16] they prepared for a paper by Alpher's PhD advisor George Gamow. [17] Alpher and Herman were able to estimate the temperature of the cosmic microwave background to be 5 K. [18]
1938: Walther Nernst re-estimates the cosmic ray temperature as 0.75 K. [2] 1946: The term "microwave" is first used in print in an astronomical context in an article "Microwave Radiation from the Sun and Moon" by Robert Dicke and Robert Beringer. 1946: Robert Dicke predicts a microwave background radiation temperature of 20 K (ref: Helge Kragh)
Differences in the temperature of the cosmic background are smoothed by cosmic inflation, but they still exist. The theory predicts a spectrum for the anisotropies in the microwave background which is mostly consistent with observations from WMAP and COBE. [6] However, gravity alone may be sufficient to explain this homogeneity. [7]
The discovery of cosmic microwave background radiation constitutes a major development in modern physical cosmology. In 1964, US physicist Arno Allan Penzias and radio-astronomer Robert Woodrow Wilson discovered the cosmic microwave background (CMB) , estimating its temperature as 3.5 K, as they experimented with the Holmdel Horn Antenna .
The interpretation of the cosmic microwave background was a controversial issue in the late 1960s. Alternative explanations included energy from within the solar system, from galaxies, from intergalactic plasma and from multiple extragalactic radio sources. Two requirements would show that the microwave radiation was truly "cosmic".
CMB spectral distortions are tiny departures of the average cosmic microwave background (CMB) frequency spectrum from the predictions given by a perfect black body.They can be produced by a number of standard and non-standard processes occurring at the early stages of cosmic history, and therefore allow us to probe the standard picture of cosmology.
Structure formation began some time after recombination, when the early universe cooled enough from expansion to allow the formation of stable hydrogen and helium atoms. [7]: 6 At this point the cosmic microwave background(CMB) is emitted; many careful measurements of the CMB provide key information about the initial state of the universe before structure formation.
The "axis of evil" is a name given to an unsubstantiated correlation between the plane of the Solar System and aspects of the cosmic microwave background (CMB).It gives the plane of the Solar System and hence the location of Earth a greater significance than might be expected by chance – a result which has been claimed to be evidence of a departure from the Copernican principle. [1]