Suppose we could understand the laws of nature that govern the particles and their interactions, and in addition why the laws are as they are, and also how the universe evolved and perhaps even how it originated—an active research area today That understanding—a theory—would be formulated not in terms of everyday units, but rather units built from constants such as the speed of light, Planck's constant and Newton's constant. From these constants one obtains the natural scales: the Planck length and the Planck mass I will call this theory the primary theory, a name I like because it suggests that as we go through a hierarchy of effective theories, from macroscopic sizes to atoms to nuclei, we end at a primary one that is not related to another at a deeper level.
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February 1997
February 01 1997
String Theory Is Testable, Even Supertestable
Many believe that superstring theory, because of its extraordinarily tiny length Scale and gargantuan energy Scale, Cannot be tested. That belief is a myth.
Physics Today 50 (2), 40–42 (1997);