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The scientific method includes the following steps:
Observation takes place in the first and fourth steps.
In cosmology, the original observation was that we seem to live in a firmament. The sun seemed to rise and set, travelling on a huge transparent bowl which was set around our world. Various paradigms which explained our world, came and went, but the universe seemed static. Even Einstein believed this.
In the 1920s Edwin Hubble of Mount Wilson observatory [1], observed that the galaxies, on the whole, were moving away from each other. Thus we live in an ' expanding universe'. The speed of expansion was apparently constant ( Hubble's 'constant'), as evidenced by light from the galaxies, which was doppler-shifted in color toward the red side of the spectrum.
Einstein correspondingly modified his field equation. See Cosmological constant
If the universe is expanding, then it must have been much smaller and therefore hotter and denser in the past. George Gamow hypothesized that the abundance of the elements in the Periodic Table of the Elements, might be accounted for by nuclear reactions in a hot dense universe. He was disputed by Fred Hoyle, who invented the term ' Big Bang' to disparage it. Fermi and others noted that this process would have stopped after only the light elements were created, and thus did not account for the abundance of heavier elements.
Gamow's prediction: One consequence of this hypothesis was a 5 - 10 Kelvin black bodyIn physics a black body is an object that absorbs all light that falls onto it: no light passes through it nor is reflected. Despite the name, black bodies do radiate light. The term "black body" was introduced by Gustav Kirchhoff in 1862. The light emitt radiationRadiation generally means the transmission of objects or information from a source into a surrounding medium or destination. Within physics, related concepts are: Ionizing radiation is a stream of particles (photons or other particles) with sufficient ene temperature for the universe, after it cooled during the expansion.
In 19651965 was a common year starting on Friday (the link is to a full 1965 calendar). Events January-February January 4 United States President Lyndon Johnson proclaims his " Great Society" during his State of the Union address. January 14 Prime Ministers of N, Arno A. Penzias and Robert W. Wilson2001 The cosmic microwave background radiation (CMB is a form of electromagnetic radiation that fills the whole of the universe. It has the characteristics of black body radiation at a temperature of 2. It has a frequency in the microwave range. CMB and t announced that microwave radiation was surrounding us in all directions, at a level which was of the order of magnitude predicted by Gamow. Penzias and Wilson got the Nobel Prize for this discovery.
After this piece of evidence, Gamow's hypothesis was now more likely. The age of the universeAlternate uses: See Universe (disambiguation In the first half of the 20th century, the word universe was used to mean the whole spacetime continuum in which we exist, together with all the energy and matter within it. Attempts to understand the universe is currently estimated to be 13.7 billion years after the Big Bang.
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