Put another way what are the required constants, primary laws and forces needed for complex life on a planet to exist?
You must have many precise things.
First of all you must have water. Water has the capacity to absorb heat from a sun, and to regulate temperatures on a home planet. It’s liquid state is vital to absorb and transport chemical nutrients necessary for life.
A home planet must have a precise distance from its home star. It must be located in the “goldilocks zone” (not too hot, not too cold, but just right) from its sun. To close to a sun it becomes like Mars, desolate and hot. Too far away and it becomes cold, destroying complex and simple life forms.
A home planet’s crust must have plate-tectonics to regulate it’s interior temperature. Check out this web address for more on plate tectonics and how they affect the earth.
A planet must have a molten iron core to generate a protective, magnetic shield to divert deadly solar winds from its sun. Learn more here.
A planet must have an oxygen rich atmosphere of nitrogen, oxygen and carbon dioxide (78%,21%,1% respectively) ensuring a temperate climate, protection from solar radiation, and the correct combination of gases to sustain a liquid water presence and complex life.
A planet must have a moon with a gravitational pull on it that sustains the planet’s angle of its axis. In the case of our earth it is a tilt of 23.5 degrees which ensures temperate seasonal changes mild enough to sustain complex life. Learn more here.
A habitable planet must have a proper relationship in distance and size from it, its orbiting moon and its sun to maintain proper gravitational effects on it’s liquid water tides, and rotational tilt.
The type of star (sun) must be right in size to ensure proper gravitational pull on the planet without affecting its rotation.
There must be a series of giant planets within a home planet’s solar system to help shield it from comets and asteroids that could wreck havoc on it by steering them away with their gravitational fields, or taking the impact instead of the home planet.
Take away any of these variables and life, including even the simplest, just cannot be sustained. Visit this link for an overview.
Some researchers believe that the chances of having all of these factors at one place, at one time in the galaxy is 1 in 1 trillion, even when considering there are billions of galaxies in the universe.
In a recent edition of Harper’s Magazine, an MIT physicist wrote that because such factors are necessary for life to exist a growing number of philosophers, and scientists have joined theologians in accepting fine-tuning and the anthropic principle as evidence of the existence of God.
He wrote about the 2011 Christian Scholars’ Conference at Pepperdine University, where Francis Collins, a leading geneticist and director of the National Institutes of Health, said, “To get our universe, with all of its potential for complexities or any kind of potential for any kind of life-form, everything has to be precisely defined on this knife edge of improbability…. [Y]ou have to see the hands of a creator who set the parameters to be just so because the creator was interested in something a little more complicated than random particles.” Alan P. Lightman, The Accidental Universe, Science’s Crisis of Faith,” Harper’s Magazine, Dec. 2011.
But of course any explanation that excludes a divine creator is what many are looking for to explain the universe and its creation. Some even look to a rather new explanation in the “Bubble Universe” theory. It claims that there are countless numbers of universes with different properties and laws. Some will have no life at all. Others will have life forms, ranging from primitive one celled to more complex with observant thinking capability. Though it cannot be explained how such multi-universes came into being, where they are at, and since we cannot observe them, we must still believe in them; you know just have faith that they exist.
Well, at least it’s a step into the direction of having faith. How long will it be before that faith leads to an all mighty, thoughtful creator?