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E = mc² by David Bodanis, Macmillan, £14.99, ISBN 0333780337

WHAT a brilliant idea for a book: a short, snappy account of E = mc²,
the most famous equation in science. The wonder is that no one
thought of it sooner. Almost a century has passed since Einstein unveiled this
most astonishing implication of his special theory of relativity—so
astonishing, indeed, that even he felt moved to add a question mark to the title
of the paper containing its derivation: “Does the inertia of a body depend on
its energy content?”

And no wonder. c² is the square of the speed of light, which brings
in a factor of 10¹⁷ in metric units. So the equation states that crammed into
every kilogram of matter is enough energy to equal a nuclear power station’s
annual output.

Many people sense the importance of Einstein’s equation, even if they can’t
say quite why. Now David Bodanis has set about satisfying this huge latent
curiosity with a book that is accessible, hugely enter-taining—but
littered with inaccuracies.

According to Bodanis, the trouble with previous attempts to explain
E = mc² is that they are full of more or less incomprehensible
stuff about “little trains or rocketships or flashlights”. This has prompted him
to take a different and undoubtedly more appealing approach, in which he
explores the story behind the five components that make up the equation, before
tackling its derivation by Einstein, and its impact on the world at large. So we
are treated to a series of fascinating human interest stories: how the French
chemist Antoine Lavoisier helped pin down the concept of mass, for example, and
how the Danish astronomer Ole Rømer first showed that the speed of light was
finite.

Even readers familiar with these stories are likely to find something new in
Bodanis’s treatment of them: how Lavoisier’s slighting of a leader of the French
Revolution led to his being guillotined, for example, or the trouble Rømer had
getting credit for his discovery. These, and many other tales, were new to me,
at least. The trouble is, I’m not sure how much faith I can place in them. For
where Bodanis deals with subjects with which I am familiar, he is less than
reliable.

To illustrate the darkest implication of E = mc², for
example, he focuses not on the Allied efforts to build an atomic bomb, but those
of Nazi Germany. Which would make a fresh angle—except that the Nazis
never had a Manhattan Project.

There are many other blunders. Einstein’s prediction of light-bending was not
confirmed from photographs taken in Brazil, but by plates taken by Arthur
Eddington off the African coast. Robert Oppenheimer was not the originator of
the implosion method for atomic bombs.

But worse still are the scientific howlers that litter this account. For a
book whose central theme is energy, he shows a shocking disregard for its
definition, routinely mixing it up with power. At one point, he talks
meaninglessly of the energy locked up in a pound of mass as being “greater than
all the power stations on Earth”.

Time and again he talks of such nonsensical concepts as “the high-speed
frictional heat of E = mc²“, and “the electricity of protons”.
His attempts to explain the physics behind E = mc² are as
risible as they are incomprehensible.

At one point, Bodanis describes how The New York Times sent its
golfing correspondent to cover the confirmation of Einstein’s prediction of
light-bending, patronisingly describing the man as a “good journalist” but
“somewhat less good, however, in having the slightest clue what was going on
here”. A 17th-century proverb about people in glass houses comes to mind.