The strong force, for example, diminishes as temperatures rise, and thus it was considerably less powerful in the early universe than it is today. And although these three forces act with very different strengths in the present universe, our calculations indicate that they were all approximately equally powerful when the temperature of our universe was somewhere around 1028 degrees. Many physicists see this as an indication that these three forces are not as independent as they might seem, but are instead each a manifestation of a single, unified force. In fact, there are many features of the
...more
