zaybu said:
The difference is that there is evidence in supporting relativity, otherwise the theory would have been thrown away a long time ago. However, there no evidence supporting the idea of extra dimensions, and I don't think that can be falsifiable. To me, that smells of science fiction. At this point, I might as well believe in the supernatural, and in case you might be wondering, I don't believe in that nonsense as well.
I do not advocate string theory, but I think it's still fair to say this:
From the point of view of a string theorist, there is certainly rational reason to believe in extra dimensions, simply because given the premises in string theory, and the conjecture that elementary particles are rather excited strings, then this together with some convenctional QFT stuff follows as consistency constraints. This logic is there, and it's a different kind of "supporting argument".
I can see that, even if I don't buy into string theory.
But my argument isn't that "I don't like" extra dimensions. My doubt is two-fold.
First of all I simply don't find the initial premises and baggage that leads to string theory, plausible or deep enough anlysis of the problems to yield my any faith in whatever that leads to by consistency. Also I see no deep conceptual reason to accept the string starting point. Apart from the original motivation of strong interaction, it seems more like a mathematical "what if" game.
The other idea is that I can accept a random speculation, if it indirectly helps the scientific process, which then indirectly, if it proves itself, is support for the originally random conjecture. However, it seems that the string conjectures doesn't help the decision process, it rather instead obscures it by suggesting a whole landscape of possible ideas. One may at some point ask how much deeper in that hole we should keep digging before reflecting upon wether something is missing, or wether something in the initial analysis that lead us here is wrong.
In that perspective I definitvely agree that all these multiverse ideas etc are steps in the wrong direction. One has to be able to distinguish between real possibilites in a decision process, each of one makes a difference, and ideas of different universes with totally different laws where we are simpyl for some reason stuck in one of them. The latter type of "possibilities" are not making any difference to the scientific process unless there is an algorithm or way of navigating/selectin between this possibilities. This is precisely as far as I know what's lacking in string theory.
I think that the supposed answer to the "what if game" is that it seems to lead us into a space of possibilities where we can not navigate. I think this alone, doesn't seem like anything that helps the scientific process.
It's the navigation process we need to understand. This is also the essence of evolution. String theory seems to paint up some gigantic space of states of laws, deduced from a what if assumption, but lacking selection principle.
Science should not try to make a list of all possible truths. That's meaningless unless there is a learning mechanism. Science IMHO should focus on the learning. Poppers abstraction is an attempt to bring order to this inductive process. I think one can critique popper without favouring string theory.
Poppers abstraction of the scientific method misses the same thing that ST does; the logic of how the generated a new hypothesis once one is shot down. This is the learning step. ST, makes a hypothesis SO complex that all resources are going into the descriptive process of defining all the possibilities. To the point where the learning process is STALLED.
If ST could replace the falsification with an efficient algorithem that with experimental feedback quickly converges in hte landscape then fine. BEcause then the "corroboration" would be convergence. If the strategy divergeces (like is certainly SEEMS to do!) then it's "wrong" (ie it doesn't work). But even that seems lacking.
/Fredrik
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