'The everyday world we experience is not always a reliable guide to physical reality.' Photo: Book cover of What’s Eating the Universe? And other cosmic questions, by Paul Davies
What’s Eating the Universe? And other cosmic questions, by Paul Davies
Review by Reg Naulty. Author: Paul Davies.
This book, written with Paul Davies’ trademark clarity and humour, answers many questions we may have about contemporary physics. For example, does it still believe in anti-matter? Somewhat embarrassingly, we read that the first anti-matter particle, the positron, an electron with a positive charge, was discovered ninety years ago. On another topic, it is rather disconcerting to learn that most cosmologists known to Davies believe that there are an infinite number of universes.
The everyday world we experience is not always a reliable guide to physical reality. For example, the minute world is not a scaled-down version of the clearly-defined objects we see around us. According to Davies, it is indeterminate and fuzzy, a world well beyond our senses. Likewise we learn of black holes, which are not completely black but glow with radiant heat that causes them to lose energy, shrink and eventually explode.
Among the unexpected changes to recent theory is the disappearance of gravity as a force. We forget that when it was first introduced to science it was controversial. How could the force of gravity hold the moon in orbit when there was nothing between the Earth and moon but empty space? Leibniz accused Newton of dabbling in the occult. Now, the force of gravity has been replaced by geometry: the Earth follows the shortest path through space warped by the mass of the sun.
The trust in mathematics as a guide to reality is reminiscent of Plato, who believed that the senses do not reveal true reality, but the mind does by recognising abstract truths. Paul Davies is in that tradition: ‘The key to the universe… resides in laws of nature that transcend the physical world and occupy an abstract plane, invisible to the senses but nevertheless within the grasp of human reason.’
In other words, the laws of nature are metaphysical. They are the great goal of science. What gives them their abstract status, according to Davies, is that they must have existed prior to the universe because they determined how the universe came into existence. Davies is at pains to point out that they were not there before the universe, because time did not exist before the universe; it came into existence with the universe. Rather the laws transcend the universe. They are in a different reality. In an interview he gave thirty years ago, Davies said that these timeless truths had to be underpinned by something similarly timeless, the implication being that they were ideas in the mind of God. He doesn’t go that far in this book.
In support of his position, Davies writes that we can make sense of nature because we find sense in it ‘in all its rational majesty’, which is revealed in its harmonious mathematical unity. That seems to be the ultimate revelation for many – a conceptual one. The contrast is with a mystical revelation. That one is experiential.
