Tuesday, October 12, 2010

The Grand Design? Part Two

Professor Edgar Andrews continues his review of The Grand Design by Stephen Hawking and LeonardProfessor Edgar Andrews reviews The Grand Design by Stephen Hawking and LeonardMlodinow (Bantam Books, September 2010):
Mighty M-theory
Chapter 5 surveys the development of physics during the past 200 years, including general relativity (which describes the large-scale behaviour of the universe) and quantum mechanics (which describes its microscopic behaviour). Although containing nothing new, this is by far the best part of this book.

The chapter concludes, however, with comments on M-theory that rang alarm bells (p.118). In the book’s opening chapter, M-theory is no more than ‘a candidate for the ultimate theory of everything, if indeed one exists’, and is ‘not a theory in the usual sense’ but ‘may offer answers to the question of creation’. Physicist Lee Smolin is doubtful: ‘… we still do not know what M-theory is, or whether there is any theory deserving of the name’ (The Trouble with Physics, Allen Lane 2007, p.146). Indeed, on p.117 the authors themselves admit that ‘people are still trying to decipher the nature of M-theory, but that may not be possible’.
But suddenly on p.118 this intractable mathematical model is somehow transformed into a theory so powerful that its laws are ‘more fundamental’ than the laws of nature and ‘allow’ for ‘different universes with different apparent laws’. This is a huge leap of atheistic faith.




Witches brew
The final three chapters rapidly descend into a witches brew of speculation and misinformation, confusingly blended with normal science. It certainly gave me a mental hangover — and I am no stranger to the territory. It is difficult to discern where science ends and speculation begins, but the key reasoning seem to be as follows.
1. The ‘big bang’ model predicts that the universe began life as such a tiny object that quantum theory must be applied to its origin (p.131). But hold on a moment! Quantum theory has only been validated under normal conditions of space, time, pressure, temperature and so on. We cannot know whether it applies to the supposed conditions at the origin of the universe, when space was intensely warped, time was at best fuzzy, and the pressure and temperature both approached infinity. What we do know is that massive objects do not exhibit quantum behaviour. No one can be sure that a new-born universe would obey quantum theory as we know it.

2.  ‘In the early universe all four dimension [of space-time] behave like space’ allowing us to ‘get rid of the problem of time having a beginning’ (pp.134-135). But if time and space were equivalent, and time did not begin, then space didn’t begin either! The universe was still-born. In fact the authors are appealing to the ‘no-boundary’ model described by Hawking 22 years ago in A Brief History of Time but are economical with the truth. The earlier book makes it clear that the model is valid only in imaginarytime, not in real time (see WMG p.121). But here this caveat vanishes and imaginary time is misrepresented as real time.
The narrative then descends into farce. They claim that ‘the realisation that time behaves like space … means that the beginning of the universe was governed by the laws of science and doesn’t need to be set in motion by some god’ (p.135). So apparently the universe did ‘begin’ after all, but not in time. Confused? Me too.

3. Picturing the early universe as a quantum particle (something they themselves describe as ‘tricky’) the authors consider how it might evolve from point (state) A to point (state) B by applying Feynman’s sum-over-histories method thus:

‘[Since we are considering the beginning of the universe] there is no point A, so we add up all the histories that satisfy the no-boundary condition and end at the universe we observe today. In this view the universe appears spontaneously, starting off in every possible way. Most of these correspond to other universes.’
But by saying that point A does not exist they assume that the universe springs into existence somewhere between nothing (point A) and the present universe (point B). This tells us nothing about how or why the universe began; simply that it did begin. We knew that already.
4. Finally, p.180 does offer an explanation of spontaneous creation. The conservation of energy means that universes can only be created from nothing if their net energy is zero, with negative gravitational energy balancing out the positive energy of matter and radiation. This necessitates that a law of gravity must exist. Because a law of gravity exists it must and will of itself create universes out of nothing (no reasoning given).
So gravity is God. Unfortunately the authors have no time to tell us who created gravity (earlier they rule out God because no one could explain who created him). Nor can they tell us why matter and gravity should pop out of nothing, except to argue that ‘nothing’ undergoes quantum fluctuations. However, this requires that (like gravity) the laws of quantum mechanics pre-existed the universe and that ‘nothing’ possesses the properties of normal space, which is part of the created order and cannot be its antecedent.

A grand design? Only in the sense that this book is grandly designed to bamboozle the unwary and cloak atheistic philosophy in the garb of science. Fortunately, the clothes don’t fit.
adrian warnock

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