Fine Tuning and the Laws of Nature

Another difficult point concerns whether we could say that divine design “used fine tuning” if the fundamental laws of physics were in fact all-dictating laws: laws with no free parameters. It could at first seem that there would then be just no way in which anything could be tuned. The strength ratio between electromagnetism and gravity, for instance, would have to be what it was, given that the fundamental laws were what they were, and so would the masses of the neutron, the proton and the electron. Once the laws were in place, no divine designer could have been faced with a range of possibilities among which he could have chosen cunningly. All the same, there could be room for talk of “fine tuning”, I suggest. For suppose that many slightly different systems of fundamental law, each dictating exactly how events would have developed, would all of them have led to the existence of a universe containing forces recognisable as gravity and electromagnetism, and particles recognisable as neutrons, protons and electrons, but with the precise properties of those forces and particles differing in each case. I suggest that a divine designer could then be said to have “fine tuned” the properties by choosing the fundamental laws appropriately.

When even the distinction between “God’s using physical laws” and “God’s operating through miraculous acts of interference” can become fuzzy, this field is going to supply plenty of work for philosophers like me. But unfortunately it may not be work which settles anything of much importance. It may simply amount to recommending various ways of using words, on disappointingly arbitrary grounds. What does seem to me important, however, is that we distinguish firmly between divine selection and observational selection. Many scientists who describe our cosmic situation as “fine tuned for life” believe that observational selection is at work here. They think that a gigantic cosmos includes hugely many domains worth calling “universes”. The many universes might be widely separated in space, in a cosmos that had inflated enormously; or they might be successive oscillations of an oscillating cosmos; or they might spring into existence entirely independently. Now, several mechanisms have been proposed for making the various universes differ in the strengths of their forces, in the masses of their particles, and in other respects as well. Brandon Carter’s “anthropic principle” then reminds us that only life - permitting conditions give rise to beings able to observe them.

Contributed by: Dr. John Leslie