When Michio Kaku was eight, he learned that a great scientist had died, and when he looked in the newspaper there was a picture he found impossible to forget.
It was a photo of Einstein’s desk, with an open notebook on it. Its pages revealed that the man some believe to be the smartest human being who ever lived had worked on a problem that even he had been unable to solve.
Young Kaku was upset. “What could be so difficult that even the great Einstein couldn’t solve it?”
Later, after training as a physicist himself, Kaku learned what it was. The universe seems full of separate forces and events. There is the blowing power of the winds, the crackle of electricity, the dazzling heat of the sun. But were they really separate or was there a hidden unit behind them that we might finally see one day?
The intense and religious Isaac Newton had taken the start. Apples fell to the ground in Lincolnshire the same way the Moon “fell” around the entire planet in its orbit. From his 17th century equations, much of the 19th and 20th century bridges, skyscrapers and rockets could be built.
During the days of the American Civil War, the whimsical Scottish thinker James Clerk Maxwell showed that the seemingly disparate forces of electricity and magnetism were only manifestations of one deeper force – the somewhat referred to as ” electromagnetism”. Craftsmen had already made simple versions of electric motors and lights. Maxwell accelerated this, and today’s offshore wind turbines and electric cars are the result.
Einstein kept pictures of Maxwell and Newton above his desk. He wanted to take the next steps to unify the seemingly disparate forces in our universe.
Much of his work has been successful. Even mass and energy, which seemed as far apart as two things could be, turned out to be simply different aspects of a deeper entity. (This link is specified in his famous E = mcÂ², with the atomic bomb just the most famous result.)
Far beyond that, however, Einstein couldn’t go. He was too locked in the past; too little knowledge about how subatomic particles work.
The latest effort to do better is string theory – an attempt to link the forces that govern the smallest particles of a nucleus with the gravitational force that operates on the largest scale of all: stretching the length of galaxies and beyond – of the.
It’s a majestic story, and Kaku tells it well in the Equation of god. (It helps – after making his eight-year-old proud – he’s a recognized authority on string theory himself.)
Unfortunately, this is a difficult theory to pass off to the general reader, as it inherently operates in more dimensions than we can imagine. But maybe a metaphor can give an impression of what its realization might produce.
Our universe is expanding and at an ever faster pace. In the distant future, it will either tear itself apart in the equivalent of a great “tear”, or – just as uninviting – its gradual dissipation of energy will make the continuation of all life form impossible.
But what if some future beings could create a lifeboat to another universe? In string theory, this possibility is not closed, especially because the theory is consistent with the fact that our universe is only one of the many existing bubbling universes.
Even with the limited tools of Einstein’s time, it was possible to imagine wormholes that could spread from one point in our universe to another. They wouldn’t stay open for long; nor could they link to other universes. With string theory, however, all of this could, in theory, be possible.
From the 21st century, this seems implausible. But note that our cell phones are little more than carefully sculpted clumps of metal and sand (silicon). Would anyone in Newton’s day – except perhaps the great man himself – have believed that whispering into such a metal / sand object in London could produce sounds heard almost instantly in South America?
God’s equation: The quest for a theory of everything, by Michio Kaku, Allen Lane, RRP Â£ 16.99, 240 pages
David Bodanis is the author of ‘The art of fairness‘
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