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The End of Physics by David Lindley, Basic Books, pp 275, $35

‘HAH,’ said an astronomer friend who saw me reading this book, ‘better never
than late.’ The comment was perhaps a little cruel, but understandable.
There is an adage in publishing that you can be first, or you can be best,
and still achieve success. To be the best book on a subject and first is a
bonus; to be second best and publish second (or later) is hopeless. It has
to be said that The End of Physics is neither the best book about the search
for a unified theory, nor the first. Nor is it by any means the worst; but
that simply isn’t good enough when following a path that has been so well
trodden by the likes of Paul Davies, John Barrow and Steven Weinberg.

David Lindley offers us an absolutely standard account of modern physics, in
three parts. The first begins with the 19th-century concept of atoms and
delves inwards to the subatomic world of quarks and the like. The second
part starts with the work of Albert Einstein and Edwin Hubble that led to
the realisation that the Universe is expanding, and takes us forward to the
discovery of ripples in the microwave background radiation by the Cosmic
Background Explorer satellite, which provided proof of their theories.

Then he describes how well the discoveries from the world of the very small
match those from the Universe at large.

‘Ho hum,’ you might well say. ‘Haven’t we heard it all before?’ We have – in
the pages of this magazine, and elsewhere. This version reads very well as a
quick overview of modern physics, but it contains nothing new, and it omits
many details which some might regard as rather important. How is it
possible, for example, to discuss the investigation of the subatomic world
without mentioning the work of J. J. Thomson, who discovered the electron
and thereby proved that the atom is divisible? Why does the discussion of
Louis de Broglie’s work fail to mention the direct influence on him of
Einstein’s work on light quanta? How is it possible to explain the birth of
quantum mechanics without discussing the roles of Werner Heisenberg and
Paul Dirac, and without mentioning Max Born at all?

The worst howler of all appears on page 84, where Lindley tells us that
‘around the Earth, because of the presence of the Earth’s mass, space is
curved, and a straight line is a circle’. This is a common misconception,
but not one that I would expect to be aired by someone with a doctorate in
astronomy. In general relativity, ‘straight lines’ are defined by light
rays, or geodesics. A light ray certainly does not follow a circular orbit
around the Earth. The curvature that describes the orbit of a satellite
around the Earth has to do with space-time, not just space; the circular
closed orbit he describes is that found close to a black hole, where light
itself does follow such a ‘straight line’.

Lindley also claims that quantum mechanics undermines the idea of causality.
This seems at best a confused interpretation of the evidence. Quantum
mechanics removes predictability, in the classical sense, in certain
circumstances. But even in quantum theory, causes precede their effects.

The book makes one attempt to put a new gloss on the old story. It is
subtitled ‘The myth of a unified theory’, and Lindley suggests that science
is so well explained by mathematics because ‘we reserve the name ‘science’
for anything that mathematics can handle. If it’s not mathematical to some
degree at least, it isn’t really science.’ He then drops the theme, but
picks it up right at the end of the book. A unified theory, a theory of
everything in the sense used by Hawking and others, ‘will indeed spell the
end of physics . . . not because physics has at last been able to explain
everything in the Universe, but because physics has reached the end of all
the things it has the power to explain.’ Ho hum, indeed.