Friday, August 5, 2011

Two Smart Guys Think About The Big And The Small

Human beings look outward from Earth into a universe that is Big—“hundreds of millions” of times our everyday size. On the other end of the scale, we use technologies that work on the Small—on tiny things that are “hundredths of millionths” our size. Here we are, suspended between galaxy and proton.

Two guys who loved math (Albert Einstein and Richard Feynman) gave us equations to deal with both ends of the scale of size. Those equations are used all the time to measure and change reality. They guide everything humans design, from computers to cars to earth satellites.

Without Albert’s ideas about (big) relative motion, human beings might not send rockets into orbit, carrying systems for mapping and rapid communication. Without Richard 's contributions to (small) electro-dynamic theory, the rapid shrinking of electronic devices could not have occurred.  Literally, the pictures we have of our Universe (from the space telescopes) would not have been made.

Al's theories of Relativity and Dick's Quantum Electrodynamics are triumphs of the human mind. Applying them, engineers can grasp everything from the infinitesimal smallness of atoms to the infinite largeness of galaxies. Human beings now understand and can predict the processes that cause our Universe at each end of the scale of size.

But these two theories are not in complete mathematical harmony. 

Al and Dick and their colleagues in physics spent time trying to bridge the mathematical gap between the theory of the very large and the theory of the very small. Other physicists joined them, too. In fact several systems of equations exist to define this problem. Scientists have even given it a name: the Theory of Everything. But joining Quantum and Relative turns out to be stubbornly difficult.

A good candidate for the Theory of Everything is called by the name of its most basic concept: the string. String Theory brings together work of Al and Dick and many other smart guys to try to complete our understanding of how things work. Where classical physics defined the pieces that fly apart in high-energy experiments as "particles," another way of visualizing them is as "strings."

The usual mathematics of our lives uses three dimensions of space and one of time:

Back-forth, up-down, side-to-side, and tic-tock. (Together, these are called “space-time.”) But the maths needed to reconcile Relative and Quantum use seven more dimensions! These are "folded up." Below the size of the smallest particle, they are everywhere in the vacuum of space.

Not that this is a testable theory, since the folded dimensions are below the limit of sizes that can presently be observed by humans. "You might as well be talking about God," says a physics professor I know, "because the theories cannot be falsified, so they have to be held by faith." But the origin of these insights into the nature of our Universe is science, not myth.

And it gives a new meaning to the term “Wonder.”