In Search Of A Cosmic Super-theory
The Grand Design by Stephen Hawking & Leonard Mlodinow
The Hypercomputer named Deep Thought in The Hitchhiker’s Guide to the Galaxy comes up with an answer to "The Ultimate Question Of Life" after nine years of calculations. The answer is 42. In The Grand Design you are warned at the beginning that the answer is a lot more complicated. However, like Stephen Hawking’s other works in popular science, here too the language is simplified for non-specialist readers. You cannot, though, afford to think that neutrons and protons are names of aliens.
The Grand Design has been co-authored by Leonard Mlodinow, who had also co-authored “A Briefer History of Time” with Hawking. Leonard, a physicist, has also written for Star Trek: The Next Generation.
Hawking’s most popular work, “The Brief History of Time”, was published in 1988. The work explored a range of cosmology subjects like the Big Bang, Black Holes and light cones. It ended on the note that a unified theory of universe would reveal the "mind of God". “The Grand Design” goes a step ahead and explores M-Theory, a possible candidate for the ultimate theory of everything. With "M" standing for anything ranging from master to mystery, M-theory is a family of varied theories. It solves the problem that a single formulation or concept for the entire universe may be untenable. It allows different theories for situations, with each having its different versions of reality. The only condition being that the theories must agree in their predictions wherever they overlap. The idea can be understood as a collection of detailed maps used to represent different regions of earth. When assorted to give a complete picture the maps will show the same landscape where they overlap.
M-theory works in 11 space-time dimensions and allows for different apparent laws. "Apparent laws" here refers to the observable laws of universe, creating room for different universes with diverse set of observable laws. The theory allows for 10500 different universes each working within its own scientific sets. The authors use string theory to explain the concept of multiple space-time dimensions. In the language of logic this translates into a straw with a diameter so small that it almost appears one-dimensional. The idea being that the "invisible" dimensions are so highly curled that they almost appear non-existent.
Like in Hawking’s early work, here also, it is argued that science can provide a God-free explanation of the origin and function of universe. In The Grand Design, however the authors come across as more direct and combative. They take on questions like why the universe exists or why there is something instead of nothing. They believe that because there is a law like gravity, the universe can and will create itself from nothing. Gravity, here of course is the same force that makes the apple fall down, but has far wider implications in the cosmological terms of reference. "It is not necessary to invoke God to light the blue torch paper and set the universe going," they say. They trace the origin of belief in a supernatural being and a parallel growth of science, both as means to explain the forces of nature. The difference being that science not only aimed at explaining, but also predicting the ways of nature.
Some of the provoking concepts in the book include the theory that universe has not just a single history but every possible history, each with its own probability. Feynman’s diagrams, designed as mathematical expressions of electron interaction, are applied to conclude that the universe appeared spontaneously "starting off in every possible way".
While getting to understand Feynman’s diagrams can get tedious, an interesting analogy is provided to relieve the pain. The authors compare the spontaneous creation of universe to formation of bubbles in boiling water. While each bubble is like an alternative universe, not all last long enough to develop. A few survive to become bubbles that we can see equivalent to universes that survive.
One of the basic concepts of the book is that there is no picture-independent or theory-independent concept of reality. This dims the question of real and false and places observations in an established model or a world with set of rules. Just like in Matrix where both the physical and virtual world have their set rules and physical realities. But the concept in the book goes way beyond science fiction with a whole chapter set out to understand the nature of reality. The authors wonder if our view of reality is distorted like that of the goldfish in a curved bowl. That, however, does not mean that the goldfish can have no understanding of world beyond the bowl. It can still draw scientific laws from its distorted frame of reference and predict and approximate accordingly. Its science would be a lot more complicated than ours, but "simplicity," they say "is a matter of taste."