Did the atheist scientist Stephen Hawking unwittingly strengthen the argument for the existence of God? The question hinges on the so called ‘fine-tuning’ of the laws of physics to produce life; if the fundamental numbers in physics (such as the strength of gravity) were even slightly different than they are, it would make life impossible. To some, this is a strong point in favour of the existence of a creator—it would be too much of a coincidence if all the values underpinning the universe had by chance aligned perfectly to sustain life. However, in his book The Grand Design, Hawking and co-author Thomas Hertog argued for a naturalistic explanation based on the multiverse hypothesis. This depends on the theory of ‘cosmic inflation’, which proposes that the big bang was followed by a rapid expansion, and then by a rapid deceleration, which may have created a number of ‘pocket universes’.
Originally, Hawking and Hertog suggested that the physical laws of these pockets are radically different from one another. But such wide variation is unhelpful in explaining why we happen to live in this perfectly balanced universe. Among pockets with no matter at all, pockets completely full of matter, pockets that are very short-lived (to name just a few possibilities), the likelihood of our pocket being the way it is remains tiny. Hence in their final paper together, Hawking and Hertog imposed strict rules on the kind of pockets that could exist, limiting the variety. But this poses a problem once again; if all the pockets have identical or almost identical laws, we still have to explain why these laws are fine-tuned for the development of life. Hertog is confident that their multiverse theory may ultimately be scientifically testable, and may help to shed light on the origins of the universe. However, as long as the ‘fine-tuning’ question remains open, the idea remains popular that the laws of the universe show that it must have been designed by an intelligent creator. As Hertog comments, “Stephen would say that, theoretically, it’s almost like the universe had to be like this”.
Applicants for Physics and Natural Sciences may wish to familiarise themselves with the work of Hawking and Hertog, and to get to grips with the various theories about the beginning of our universe. Students wishing to study Theology or Philosophy should be aware of the traditional arguments for the existence of God, and may want to consider whether modern scientific research has dispelled or strengthened these arguments.