Big Bang Theory
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A Big Bang Theory was a Physics theory that postulates a Big Bang event.
- See: Physical Cosmology, Metric Expansion Of Space, Mass–Energy Equivalence, Subatomic Particle, Big Bang Nucleosynthesis.
References
2014
- (Wikipedia, 2014) ⇒ http://en.wikipedia.org/wiki/Big_Bang Retrieved:2014-3-7.
- The Big Bang theory is the prevailing cosmological model for the early development of the universe. … The earliest instant of the Big Bang expansion is still an area of open investigation. The Big Bang theory does not provide any explanation for the initial conditions of the universe; rather, it describes and explains the general evolution of the universe going forward from that point on. Georges Lemaître first proposed what became the Big Bang theory in what he called his "hypothesis of the primeval atom". Over time, scientists built on his initial ideas to form the modern synthesis. The framework for the Big Bang model relies on Albert Einstein's general relativity and on simplifying assumptions such as homogeneity and isotropy of space. The governing equations were first formulated by Alexander Friedmann and similar solutions were worked on by Willem de Sitter. In 1929, Edwin Hubble discovered that the distances to far away galaxies were strongly correlated with their redshifts — an idea originally suggested by Lemaître in 1927. Hubble's observation was taken to indicate that all very distant galaxies and clusters have an apparent velocity directly away from our vantage point: the farther away, the higher the apparent velocity, regardless of direction. Assuming that we are not at the center of a giant explosion, the only remaining interpretation is that all observable regions of the universe are receding from each other. While the scientific community was once divided between supporters of two different expanding universe theories — the Big Bang and the Steady State theory, observational confirmation of the Big Bang scenario came with the discovery of the cosmic microwave background radiation in 1964, and later when its spectrum (i.e., the amount of radiation measured at each wavelength) was found to match that of thermal radiation from a black body. Since then, astrophysicists have incorporated observational and theoretical additions into the Big Bang model, and its parametrization as the Lambda-CDM model serves as the framework for current investigations of theoretical cosmology.