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This feels off to me. Einstein’s process did not come from the mathematics, but from an idea of what was happening. This enabled a great number of odd predictions which were verified (the Sun would bend the visible pathway of a star, there would be gravitational waves, etc...). String Theory feels like a theory which is starting at the wrong place. Not an idea of what process is happening and then seeing if the results fit, but an attempt to connect all the results into a theory. Pas bien por moi!

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> String Theory feels like a theory which is starting at the wrong place.

I think there's also a place for setting aside our prescriptive rulers and looking at String Theory in its own right.

As a programme it has contributed significantly to detangling the intractibilities in quantum field theory. Heck, it apparently even finds applications in such "mundane" applications as condensed matter physics by showing coorespondences between fluids and black holes. As a pure math endeavor, it's contributions to algebraic geometry are hard to miss.

Personally, I think a lot of the "problems" with String Theory only arise when circumscribing it to be a certain kind of cosmological model.

> String Theory feels like a theory which is starting at the wrong place. Not an idea of what process is happening and then seeing if the results fit, but an attempt to connect all the results into a theory.

Are you saying that it doesn't make any predictions (and is therefore unfalsifiable)?

>"Are you saying that it doesn't make any predictions (and is therefore unfalsifiable)?"

As I understand, its the opposite. String theory "predicts" any and every possible observation, then they cherry pick whatever predictions are already accepted as fact to say there is evidence for the theory.

Sure, but regular quantum mechanics does the same thing. It's under-constrained and allows for too many possibilities. So you assume that the observations wrought by Newtonian physics must be valid and use that to constrain the theory down to something that can be useful.

The difference is that the string model doesn't (yet) have any observations which we could use to constrain it in an analogous manner. But in studying it, one would hope to find areas of the theory that indicate where those observations could be made.

The point being, it is not so simple to just look at string theory and say you can a priory determine it is flawed or wrongly motivated. That same kind of reasoning would likely have prevented Planck & Einstein from starting quantum theory.

> Sure, but regular quantum mechanics does the same thing. It's > under-constrained and allows for too many possibilities.

No it doesn’t. There are a few good guiding principles that make it possible to build models that turn out to be an accurate description of nature. These guiding principles don’t manifest themselves in a set of axioms of a mathematical theory nevertheless they are there. And they are part of the theory, just not set in stone like the underlying mathematical structure. But that doesn’t matter at all as long as you are doing science and not math.

Take classical EM, measure the masses of the electron and atomic nuclei, and write down a suitable Hamiltonians. Viola, you have an explanation of almost every phenomena that’s relevant in our daily life and way beyond. Similar principles exist in elementary particle physics and lead to standard model.

>"observations wrought by Newtonian physics"

I'm not sure what this means. Is it different from just making an observation? Eg, "this light in the sky is of this color at that location", or "this object drops at that speed".

It just means that we need the correspondence principle to find useful quantum mechanical models. Without that, you're just talking about algebras acting on Hilbert spaces.

What's the fundamental difference between making no predictions and predicting every possible observation? Both seem unfalsifiable to me...

They both are.

Well, let's say that string theory has far fewer testable predictions per unit of theorem[1] than other physics theories have.

[1] However measured (cubic meter of paper, maybe?)

Firkins, theorem volume is measured in imperial firkins.

As far as I know that's the case. At least we can't verify any predictions with the energies we can reach right now and long into the future.

There are no predictions even in principle. It has nothing to do with the predictions being at a sufficiently high enough energy level that we can't verify...

I remember reading something about a galaxy sized particle accelerator that could detect the extra dimensions of string theory.

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