What should we look for in a physical theory? What "axioms" of nature should we adopt? Should we assume certain things are true about the universe for aesthetic or philosophical reasons?
We often want to know exactly what nature is doing and once a principle is discovered we want it to be an "Eternal Truth" which all physical theories must bow in reverence to. We want physics to describe what is actually happening.
Enter Pragmatism. William James and others felt something is true if it is good and beneficial in some concrete practical way. Secondly, something is more true if it more beneficial to believe it than something else thing.
Pragmatism in Action:
Should we want fundamental physics to be related to geometry? Answer: Only if believing this is more beneficial in some concrete way. After decades of research geometry does not seem to be a very practical approach to describing particle physics so we should abandon trying to use it to describe the standard model. It is, currently, the most practical idea for gravity so we should keep that interpretation of gravity until there is a more practical explanation.
My point in all this is not to express my views. I just wanted to show how a pragmatist may think. What is important is the idea that: what is most beneficial in a practical and concrete way is the way to go. Even if the universe is background independent, and it's all about geometry, and there are not higher dimensions in reality, a pragmatic person would still use a background dependent, higher dimensional theory of quantum fields if what he/she wanted to describe was more practically and concretely described in that way.
Pragmatist: "My theory gives just as accurate results, if not better, as your theory but mine is more practical to use."
There may be some problems with GR but in view of the fact that all alternative are just not as practical then I see no reason to throw out GR at the moment, even though some Physicists are keen to do that.
ReplyDeleteOn the other hand some theories are looking more and more like Epicycles and just arn't practical. I'm all about being practical.