references to how understanding physics can impact human life on earth in the relative short-term as well as in space and far into the future. Hawking describes how statistical evidence points to the physical limits of population growth and electricity being reached on earth by the year 2600. But by applying the same statistical principles to knowledge as to population growth, to take a more comforting view of things, predicted human knowledge of how to preserve energy reserves could potentially carry the human race forward, faster to possibly attain solutions to this problem of geometric physical expansion.
There is, however, no question that having some background in physics helpful in understanding the text, even while Hawking tries to simplify basic quantum principles. For instance, as the author attempts to explain the rational behind an early and inaccurate Michelson-Morley experiment, when humans imagined that space was filled by a continuous medium called the "ether," he must go into a lengthy explanation how early physics saw "light rays and radio signals were waves in this ether, just as sound is pressure waves in air." (2) In this experiment, because no difference was found in the speed of the two perpendicular light beams, the experiment's observers concluded that ether was non-existent. Still, for a man bounded, essentially, in his own physical nutshell, Hawking has accomplished and understood a great deal in his life and is able to make at least a small 'kernel' of what he as understood, interesting and comprehensible in concrete, physical terms. Also, his book functions as a shorthand introduction to the history of physics, and the different people and concepts that played a role in physic's conceptual evolution over the short distance of human historical time.