3 ms·

If you grant arbitrarily advanced technology then "testable predictions" absolutely do exist, most immediately on the cross sections of basically every particle

If you grant arbitrarily advanced technology then "testable predictions" absolutely do exist, most immediately on the cross sections of basically every particle. We can't perform such experiments now, but that's a problem with the technology, not with the theory. Imagine if someone had said 30 years ago that the "higgs boson theory" is a failure because we couldn't then perform the experiments to detect it.

noone_important 2y ago
This comparison is not really fair. On the one hand you have the prediction of a scalar excitation with a lot of restrictions (cosmology and naturalness). On the other hand you have a giant framework that can predict or fit almost anything. Don't get me wrong, I still regard string theory as a big success. It taught us a lot about mathematics and field theories in the last decades. However the predictive nature is basically non-existant so far.
- bdjsiqoocwk 2y ago
  Nonsense. It can't predict everyone, in particular it won't predict special relativity bring violated. In addition you haven't addressed the main point here which is that when some people say "can predict" they mean "in principle it can predict" whereas other mean "can predict today with currently available technological means". Regarding the former: yes it can. I already gave the example of one such prediction, but here's another one: all particles niches have stringy modes in their spectra. Regarding the later: maybe, but thats a problem with our technology, not with the theory. I feel this conservation is going in circles already.
  - noone_important 2y ago
    Just because they are not mainstream, you definitely can have lorentz violation in string theory [0]. Spontaneous symmetry breaking can lead to induced finsler geometries, which can basically have multiple light cones (when there was the "faster than light neutrinos" result on the table. Some people used finsler spacetime to explain them). So you made your prediction only by choosing an axiom. There is a reason that even some proponents of string theory call it the theory of anything. [0] https://arxiv.org/abs/0708.2250 https://arxiv.org/abs/0708.2250
jerf 2y ago
"If you grant arbitrarily advanced technology" I don't, thus neatly resolving your issue. Neither does anybody else. Testable means something like testable today or in the designable future and it always has. As for the fact this may mean a true theory is not testable today even though some hypothetical technology in the hypothetical future wielded by hypothetical beings could hypothetically resolve the problem, well, welcome to the universe we live in. This is not special pleading applied only to string theory. It's evenly applied to everything. It's just that string theory gets hit by this particularly hard, although not uniquely so (to the best of my knowledge, loop quantum gravity is also rather short on testable predictions). The only utility of quadruply hypothetical advances is to science fiction authors. And I've greatly enjoyed many such stories. But it's important to distinguish between science fiction and what we can do in reality.

noone_important 2y ago

This comparison is not really fair. On the one hand you have the prediction of a scalar excitation with a lot of restrictions (cosmology and naturalness). On the other hand you have a giant framework that can predict or fit almost anything. Don't get me wrong, I still regard string theory as a big success. It taught us a lot about mathematics and field theories in the last decades. However the predictive nature is basically non-existant so far.

bdjsiqoocwk 2y ago
Nonsense. It can't predict everyone, in particular it won't predict special relativity bring violated. In addition you haven't addressed the main point here which is that when some people say "can predict" they mean "in principle it can predict" whereas other mean "can predict today with currently available technological means". Regarding the former: yes it can. I already gave the example of one such prediction, but here's another one: all particles niches have stringy modes in their spectra. Regarding the later: maybe, but thats a problem with our technology, not with the theory. I feel this conservation is going in circles already.
- noone_important 2y ago
  Just because they are not mainstream, you definitely can have lorentz violation in string theory [0]. Spontaneous symmetry breaking can lead to induced finsler geometries, which can basically have multiple light cones (when there was the "faster than light neutrinos" result on the table. Some people used finsler spacetime to explain them). So you made your prediction only by choosing an axiom. There is a reason that even some proponents of string theory call it the theory of anything. [0] https://arxiv.org/abs/0708.2250 https://arxiv.org/abs/0708.2250

jerf 2y ago

"If you grant arbitrarily advanced technology" I don't, thus neatly resolving your issue. Neither does anybody else. Testable means something like testable today or in the designable future and it always has. As for the fact this may mean a true theory is not testable today even though some hypothetical technology in the hypothetical future wielded by hypothetical beings could hypothetically resolve the problem, well, welcome to the universe we live in. This is not special pleading applied only to string theory. It's evenly applied to everything. It's just that string theory gets hit by this particularly hard, although not uniquely so (to the best of my knowledge, loop quantum gravity is also rather short on testable predictions). The only utility of quadruply hypothetical advances is to science fiction authors. And I've greatly enjoyed many such stories. But it's important to distinguish between science fiction and what we can do in reality.