posted on Sep, 7 2004 @ 12:25 PM
Smolin is one of the main proponents of loop quantum gravity, the 'other' theory on quantum gravity. It has not received as much attention as string
theory, but personally I feel more for it. The main conflict is that loop quantum gravity is background independant; it doesn't need a fixed
classical background to work. String theory does, although there are indications that string theory can be made background independant.
The article is from february 2003, so it's not totally up to date, but I still think it's worth reading. The article
Loop Quantum Gravity
was published in Edge, a very good magazine that I really
like. The Smolin/Susskind debate in the latest edition is also worth reading. Anyway, the abstract of the loop quantum gravity article:
It's only since the middle 1980s that real progress began to be made on unifying relativity and quantum theory. The turning point was the
invention of not one but two approaches: loop quantum gravity and string theory. Since then, we have been making steady progress on both of these
approaches. In each case, we are able to do calculations that predict surprising new phenomena. Still, we are not done. Neither is yet in final form;
there are still things to understand. But the really important news is that there is now a real chance of doing experiments that will test the new
predictions of these theories.
This is important, because we're in the uncomfortable situation of having two well-developed candidates for the quantum theory of gravity. We need to
reduce these to one theory. We can do this either by finding that one is wrong and the other right, or by finding that the two theories can themselves