Why do people think string theory is non falsifible?

People hate on string theory cause it supposedly has no predictive value and is not falsifiable. But what does that mean? The whole point of “theories of everything” like string theory is that they explain all the phenomenon that we currently explain with theories of gravity, quantum mechanics, etc. My understanding is that all the old “classic” theories can be derived from string theory.
So even if string theory makes no new predictions, then as long as it explains all the current phenomenon more simply than our current theories, then why doesn’t that make string theory at least as valid as the old theories?

“String theory” relies on a multiple folded dimension paradigm that is more an exercise in mathematical imagination than any substantive reflection of physical reality. When you can barely even explain in some reasonably rigourous fashion the underpinnings of your paradigm and how it links to physical reality, it’s going to be difficult for your construct to make enough headway to be taken seriously.

This post explains it pretty well. String theory is in principle falsifiable, but it’s effectively not due to the high number of free parameters.

Saying that the String Model predicts all that we already know of physics is sort of like saying that a typewriter predicts the complete works of Shakespeare. If I hit the ‘t’ key of the typewriter first, and then hit the ‘o’ key, and then the spacebar, and the the ‘b’ key, and then the ‘e’, and so on, a typewriter does indeed spell out “To be or not to be”. But having typed out “To be or not to be”, just owning the typewriter doesn’t give me any hint that the next words are supposed to be “that is the question”.

Likewise, the String Model has a great deal of adjustable parameters (with values analogous to the keys on your typewriter), and you can adjust some of them to get the behavior of electromagnetism, gravity, etc. out, but that still leaves a bunch of parameters you don’t know to predict the next experiment.

String Theory or M Theory doesn’t explain anything more simply, which is part of why people don’t like it. But, going further, I thought there were in fact some physical phenomena that cannot be satisfactorily predicted due to the disconnect between quantum theory and relativity. Is this not the case?

As you alll should know by now, I’m no scientist, but I do appreciate scientific standards and procedures.

I do remember seeing a PBS (I think) program on which tried to give an overview of TOE. There was a chart of some sort that some String Theory scientist was working on that placed something-something in a certain order – similar to the order of a chart of the elements. There were spaces on this chart where things were missing. The chart “needed” something to be there. Later, the missing “thing” (math formula? chemical property?) would be found and fit in. In that way the theory was predictive.

Don’t you just hate it when a lay person tries to describe something she obviously doesn’t understand?

Do any of you know what I’m referring to? Has string theory been completely tossed out the window by scientists now? I wasn’t aware that it has been completely dismissed. When was it falsified and by whom?

It hasn’t been disproven, but it’s come under increasing attack for, essentially, being mathematically sound but useless.

My layman’s understanding is that what the theorists have created is not a theory but a theory of theories–a sort of general plan for creating a physical theory. What they’ve proven, through mathematical logic rather than through experiment, is that if you take this general plan and set all the settings to the correct values, you will get a Theory of Everything. They don’t know what the correct settings are, and the number of possible ways to set them is very large, but they have proven that a correct set must exist.

The problems that many people have with this situation are, first, that the whole thing works only by assuming lots of things that are not suggested by evidence and are if not theoretically then practically untestable (such as the number of hidden, extra dimensions); and second, that the number of possible theories that can fit into the general plan is so great that we will probably never find the right one, even if we know it exists.

In other words, the argument is not that “string theory” is wrong but that it misses the point. (It’s sort of like the joke about the mathematician and the kitchen fire . . .)

This sounds to me more like the Standard Model predictions of the existence of the Top quark (maybe the Charm and Bottom quarks also?).