Our universe seems made for life; it has the right characteristics to make it possible, to let it prosper and evolve. It hosts biological activity, perhaps with a certain waste of space, for today we can observe a total extension of about 92 billion light years, or about 9 x 1023 km (= 9 followed by 23 zeros, 900,000 billion km). Anyhow, life is present here. Even if life exists only on this small planet orbiting around a star at the edge of one of the 100 billion galaxies, even in all this “waste of space,” life is present.
Is its presence an obvious affirmation, a fact taken for granted? Perhaps. But theologians, philosophers, cosmologists and scientists have been asking themselves this question for centuries: Why do the laws of nature seem to have been “fine tuned” so accurately that they allow the development of living beings? In cosmology, this is called “the fine tuning problem.” Such a state of affairs should also be an extremely important theme for men and women of faith who, with mind and spirit open to the truth, are passionate about creation.
The “fine tuning” of the universe consists in the fact that, if the laws of physics were different, even by a little, life would not be possible. And the laws of physics – as we observe them – represent only one set among all those possible, thus making the existence of our universe – governed by these particular laws – extremely improbable. And yet, it is the only one in which we live and which we can observe experimentally.
To explain the fine-tuning of physical laws, one can venture the analogy of a violinist who tunes her instrument before the beginning of a concert so as to play harmoniously with the whole orchestra. On a much larger scale and with much greater accuracy, such a thing seems to be the case with natural laws.