The Probability of Life
In a recent survey of globular cluster 47 Tucanae, scientists found zero extra solar planets out of 37,000 stars searched (Astronomers Ponder Lack of Planets in Globular Cluster from the Hubble Space Telescope).
Life simply does not appear or it would be apparent in other galaxies and on other planets. The chance that the necessary five variables would all exist together is 0.0000001 [10% x 10% x 10% x 1% x 1%] or .00001%.
The probability that the galaxy would be the right size to support life, the right galaxy type, and proper location for life are each 10%. The chance that all three exist simultaneously is 0.001 or 0.1%. The chance that supernovae eruptions and white dwarf binaries exist is 1% each or both together, 0.01%. The last two items relate to the fusion of two planetary structures into one.
All five of these characteristics must be present for life to exist. Galaxy size is important, as those that are too large tend to have a number of violent events that disturb solar orbits. Small galaxies have insufficient material to maintain star formation for long enough periods to form rocky planets.
If by some incredible miracle the galaxy had all five variables listed above there are still fundamental constants needed for a universe capable of life. Additionally, each constant must exist within defined maximum deviations for each. If even one is outside the maximum deviation or missing, life could not exist.
First, the ground state of He, Be, C, and O must exist within a maximum deviation of ± 4%. Second, the mass of a neutron must be within ± 0.1% and an electron must have a proton ratio not exceeding ± 1:1037. Third, the electromagnetic force relative to gravity must be within ± 1:1040 and the expansion rate of the universe within ± 1:1055. Finally, the cosmological constant must be within ± 1:10120.
Changing a constant more than the amount indicated could result in a universe that does not even contain matter. In many other instances, only hydrogen or light elements would exist (making life impossible). The longevity of the universe would change with any variation in the last two parameters. Many of these perturbations would result in the universe that would have ended billions of years ago.
The anthropic principle states that the universe is designed specifically for human life. Scientists holding to the weak anthropic principle believe that there must be some undiscovered underlying principle that explains why the universe seems to be designed. Those holding to the strong anthropic principle believe that the underlying reason that the universe appears to be designed is because the ultimate Intelligent Designer - God, has designed it.
The standard way to test any theory is to gather data and see which version fits the data better. So far, the strong anthropic principle fits the data better. For example, the Cosmological Constant is by far, the most constrained constant discovered to date. Initial observations suggested that the value is the closest value to zero (within 1 part in 10120) known in the universe. Subsequent observations suggest that it may be closer to 1 part in 10240. The degree of fine-tuning necessary for life to exist has led some scientists to believe in Intelligent Design.
Authors Zehavi and Dekel sum it up by writing, "This type of universe, however, seems to require a degree of fine tuning of the initial conditions that is in apparent conflict with 'common wisdom'."
The low probability of life in a galaxy, along with the small deviations of needed variables for life to exist in a universe, is strongly in favor of intelligent design. These five parameters, if all were to be within the maximum deviation, would be virtually impossible by chance. The formula (4% x 0.1% x 1.104% x 1.1055% x 1.0120%) shows the likelihood of all constants occurring by mere chance is 4.94047-11 [0.0000000000494047].
If you were to factor in the chances of all five constants required for life with the five characteristics required for a galaxy to support life, you can reasonably call the chance 0%. In fact, you could say the chances are so remote that nothing but divine intervention could possibly bring all of these factors together, within their needed tolerances, for life to exist.
If you were a betting man, are you betting on chance or intelligent design?