Cosmic fine tuning – An Introduction
The concept of cosmic fine tuning relates to a unique property of our universe whereby the physical constants and laws are observed to be balanced on a ‘razor’s edge’ for permitting the emergence of complex life. The degree to which the constants of physics must match precise criteria is such that a number of agnostic scientists have concluded that indeed there is some sort of transcendent purpose behind the cosmic arena. British astrophysicist Fred Hoyle writes: “A common sense interpretation of the facts suggests that a super intellect has monkeyed with physics, as well as with chemistry and biology, and that there are no blind forces worth speaking about in nature. The numbers one calculates from the facts seem to me so overwhelming as to put this conclusion almost beyond question.”
Cosmic fine tuning – Fundamental Constants
The ripples in the universe left over from the original ‘Big Bang’ singularity (often referred to as CMB, or cosmic background radiation) are detectable at one part in 105 (100,000). If this factor were even slightly smaller, the cosmos would exist exclusively as a collection of gas -- stars, planets and galaxies would not exist. Conversely, if this factor were increased slightly, the universe would consist only of large black holes. Either way, the universe would be uninhabitable.
Another finely tuned value is the strong nuclear force that holds atoms -- and therefore matter -- together. The sun derives its ‘fuel’ from fusing hydrogen atoms together. When two hydrogen atoms fuse, 0.7% of the mass of the hydrogen atoms is converted into energy. If the amount of matter converted were slightly smaller -- say, 0.6% instead of 0.7% -- a proton would not be able to bond to a neutron and the universe would consist only of hydrogen. Without the presence of heavy elements, planets would not form and hence no life would be possible. Conversely, if the amount of matter converted were increased to 0.8% instead of 0.7%, fusion would occur so rapidly that no hydrogen would remain. Again, the result would be no planets, no solar systems and hence no life.
The ratio of electrons to protons must be finely balanced to a degree of one part in 1037. If this fundamental constant were to be any larger or smaller than this, the electromagnetism would dominate gravity -- preventing the formation of galaxies, stars and planets. Again, life would not be possible.
The ratio of the electromagnetic force to gravity must be finely balanced to a degree of one part in 1040. If this value were to be increased slightly, all stars would be at least 40% more massive than our Sun. This would mean that stellar burning would be too brief and too uneven to support complex life. If this value were to be decreased slightly, all stars would be at least 20% less massive than the sun. This would render them incapable of producing heavy elements.
The rate at which the universe expands must be finely tuned to one part in 1055. If the universe expanded too fast, matter would expand too quickly for the formation of stars, planets and galaxies. If the universe expanded too slowly, the universe would quickly collapse -- before the formation of stars.
The mass density of the universe is finely balanced to permit life to a degree of one part in 1059. If the universe were slightly more massive, an overabundance of deuterium from the big bang would cause stars to burn too rapidly for the formation of complex life. If the universe were slightly less massive, an insufficiency of helium would result in a shortage of the heavy elements -- again, resulting in no life.
Cosmic Fine tuning – Conclusion
To believe that the facts and figures here detailed amount to no more than happy coincidence, without doubt constitutes a greater exercise of faith than that of the Christian who affirms the theistic design of the universe. Such scientific insights over the last several decades have led the late Robert Jastrow -- a self-proclaimed agnostic -- to write: “For the scientist who has lived by his faith in the power of reason, the story ends like a bad dream. He has scaled the mountains of ignorance; he is about to conquer the highest peak; as he pulls himself over the final rock, he is greeted by a band of theologians who have been sitting there for centuries.”
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