Walter Isaacson
Simon and Schuster, hbk, $55
Reveiw by Clive Trotman
‘‘Einstein died'' was a Princeton schoolgirl's class news the following day in April 1955. ‘‘My dad's got his brain,'' added a boy, truthfully.
Multiple studies revealed only that an unremarkable brain can house a remarkable mind.
The question that fascinates so many people about Albert Einstein is how he did it. What he did is well enough known if not generally well understood. In very general terms he showed - or perhaps reasoned out would be more accurate - that nothing influences the speed of light in a vacuum, which is universally constant, and that gravity and inertia are indistinguishable.
A great many consequences flowed from Einstein's pronouncements, some of them seemingly quite weird, like energy and solid matter being manifestations of the same thing. Subjectively, a small amount of matter equates with a vast amount of energy, hence nuclear power and weapons, but small and vast are concepts derived from human scale and have no objective meaning.
And of course everyone associates Einstein with the tantalising relativity of space and time, such that the very notion of ‘‘simultaneous'' events becomes a tail chasing exercise in which observers travelling at different velocities must disagree as to what they saw.
Before Einstein's great papers a century ago, Newton had it all sewn up. The Earth and the universe functioned like a perfect watch, and if you could measure every force, you knew precisely what would happen next. It was inconceivable that Newton's theories could be incorrect or even incomplete, and besides, observations fitted them convincingly.
Yet Newton's theories were incomplete, because they did not allow for the adjustments of relativity that become noticeable at Star Trek velocities. But whether relativistic corrections are noticeable is one thing, whether they exist is quite another.
They do exist, however microscopic they may be at everyday relative velocities, and will never go away. Any theory that ignores them is worse than inaccurate, it is without foundation.
So how did Einstein do it in his 20s? He exercised a supreme freedom of imagination, of thought-experiment, an exquisite skill in discarding preconception. What happens if you sit on an advancing beam of light? What happens if an observer on a train (moving exceedingly fast) and another sitting on the embankment compare notes about simultaneous events? Very surprising things.
The author is not a scientist but a captain of industry, biographer and president of the Aspen Institute, which promotes ‘‘timeless values''. His new angle on Einstein, compared with countless earlier books about the man, derives from the release of Einstein's personal papers, authorised to happen 20 years after the death of his step-daughter.
A comprehensive and well annotated volume of 675 pages draws together surely most of what there is to know about the man, his genius, formative years, two wives and complicated loves.
- Clive Trotman is a Dunedin science writer and technical arbitrator.
