**book** :

*The Elegant Universe : Superstrings, Hidden Dimensions, and the Quest for the Ultimate Theory* by Brian Greene

Good read. Very good read.

Greene approaches the entirety of modern physics history in an extremely understandable manner. He begins with the three major problems that have stood in front of physicistsduring this century and how they were or will be solved.

The first problem was that of the fast and heavy, meaning matters of high speed and high density. The answer of course were Einstein's Special Theory of Relativity (constant velocity) and General Theory of Relativity (added accelerated motion as symmetrical with gravity), both of which fundamentally changed our concepts of spacetime (and the universe in general) The second problem was that of the small. The work from Heisenberg, Planck, and many others came up with the Quantum Theory which explained how things became *very* weird on the smallest of scales, once again changing our most basic beliefs -- like the smoothness of spacetime. The final problem was fitting these two concepts together. When trying to merge the equations for quantum theory and relativity, answers of infinity were fairly common (a result which almost always signals major problems.) And the answer for this rsulting problem is still under investigation : it's string theory.

What string theory attempts (apparently successfully) to do is to "smooth" over the rough spots between the two previous theories. It does this in saying that point particles (what electrons, quarks, etc were always believed to be) actually consisted of vibrating strings. Getting rid of the massive (meaning non-massless) point particles and replacing them with a system of harmonics gets rid of the infinities in the earlier equations. Plus, string theory promises to be the Ultimate Theory, the one which unifies all knowledge about the workings of the universe. But, we'll have to wait, that'll take a bit...

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Amazon.com information:*

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Paperback - 448 pages (February 29, 2000) *

Vintage Books; ISBN: 0375708111 ;

Dimensions (in inches): 1.01 x 8.01 x 5.23