English astronomer Fred Hoyle is credited with coining the term "Big Bang" during a talk for a March 1949 BBC Radio broadcast,[42] saying: "These theories were based on the hypothesis that all the matter in the universe was created in one big bang at a particular time in the remote past."[43][44] However, it did not catch on until the 1970s.[44]
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The term itself is a misnomer as it implies the occurrence of an explosion.[44][52] However, an explosion implies expansion from a center point out into the surrounding space. Rather than expanding into space, the Big Bang was the expansion/stretching of space itself, everywhere simultaneously (not from a single point), causing the universe to cool down and the density to be lowered.[53][54] Another issue pointed out by Santhosh Mathew is that bang implies sound, which would require a vibrating particle and medium through which it travels. Since this is the beginning of anything we can imagine, there is no basis for any sound, and thus the Big Bang was likely silent.[46] An attempt to find a more suitable alternative was not successful.[44][47]
After World War II, two distinct possibilities emerged. One was Fred Hoyle's steady-state model, whereby new matter would be created as the universe seemed to expand. In this model the universe is roughly the same at any point in time.[72] The other was Lemaître's Big Bang theory, advocated and developed by George Gamow, who introduced BBN[73] and whose associates, Ralph Alpher and Robert Herman, predicted the CMB.[74] Ironically, it was Hoyle who coined the phrase that came to be applied to Lemaître's theory, referring to it as "this big bang idea" during a BBC Radio broadcast in March 1949.[49][44][notes 3] For a while, support was split between these two theories. Eventually, the observational evidence, most notably from radio source counts, began to favor Big Bang over steady state. The discovery and confirmation of the CMB in 1964 secured the Big Bang as the best theory of the origin and evolution of the universe.[75]
In 1964, Arno Penzias and Robert Wilson serendipitously discovered the cosmic background radiation, an omnidirectional signal in the microwave band.[75] Their discovery provided substantial confirmation of the big-bang predictions by Alpher, Herman and Gamow around 1950. Through the 1970s, the radiation was found to be approximately consistent with a blackbody spectrum in all directions; this spectrum has been redshifted by the expansion of the universe, and today corresponds to approximately 2.725 K. This tipped the balance of evidence in favor of the Big Bang model, and Penzias and Wilson were awarded the 1978 Nobel Prize in Physics.
The big bang approach is the approach of combining all modules at once and then performing verification of the functionality after the individual modules are tested. It belongs to the category of integration testing of the applications.
The big bang is diametrically opposed to the supernatural creation described in the Bible. Furthermore, there are many other differences between the big bang and the biblical account of origins. For example,
The big bang model predicted that the universe ought to be filled with radiation in the microwave part of the spectrum having a temperature of only a few Kelvin (K). This radiation, referred to as the Cosmic Microwave Background, supposedly comes from a time a few hundred thousand years after the big bang. When the Cosmic Microwave Background (often abbreviated CMB or CBR) was then discovered in 1964, and which was now a successful prediction of the big bang. Other cosmologies like the steady state model fell out of favor and the big bang assumed the position as the most popular of the naturalistic cosmologies. Ironically, it was a staunch opponent (and steady state proponent) of the Cosmic Egg hypothesis, who gave it the name we use today. Sir Frederick Hoyle mockingly nicknamed it the big bang and the name stuck.
As it turns out the CMB was the one successful prediction of the big bang model, but there are many problems with it. But for every problem that crops up, a new addition to the model is proposed which rescues the paradigm. But there is no proof for any of these rescuing devices; and no real empirical data to refute the following problems with the big bang.
The big bang model proposes that matter (hydrogen and helium gas) was created from energy as the universe expanded. However, experimental physics tells us that whenever matter is created from energy, such a reaction also produces antimatter. Antimatter has similar properties to matter, except the charges of the particles are reversed.
The big bang model by itself can account for the existence of only the three lightest elements (hydrogen, helium, and trace amounts of lithium). This leaves the other naturally occurring elements unexplained. Since the conditions in the big bang model are not right to form these heavier elements, secular astronomers believe that stars have produced the remaining elements by nuclear fusion in their cores, which then distribute the heavier elements into space when they exploded (went supernovae).
According to the big bang model, the universe suddenly appeared 13.8 billion years ago in a very dense, hot state that expanded into the universe that we see today. But cosmologists realized that there were problems with the CMB. One of these was the horizon problem: the CMB observed from opposite parts of the sky had precisely the same temperature. But how could that be?
The cold spot is about 10 degrees in diameter, and it has an average temperature of 70 μK (0.00007 K). In contrast, the temperature fluctuations attributed to density variations in the early universe extend over much smaller parts of the sky and typically differ by only 18 μK from the average CMB temperature. Furthermore, some portions of the cold spot are 140 μK cooler than the average CMB temperature. Not only that, but the Cold Spot is below the ecliptic plane, which typically has higher temperatures than areas above the ecliptic plane. This result is puzzling to cosmologists. There have been several proposed explanations for the cold spot. One suggestion is that it is the result of a supervoid in direction of the cold spot. A more fanciful proposal is that this is the signature of another universe that left its imprint on our universe during cosmic inflation that hypothetically happened shortly after the big bang. But most cosmologists seem to be content to ignore the cold spot too. 2ff7e9595c
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