Why do you think his kind almost never claim that the Laws of Motion back up their stuff? Or that the laws of electromagnetism back them up (although, some of them do try this)?
Because other parts of physics are not on the side of the mystics and do not seem so nonsensical.
It is just too easy to appeal to quantum physics. It seems so strange and mystical, yet it is supposed to be science!
What kind of attitude do you think that fosters about science?
Not a good one …
Of course, there can be. I see no reason why someone could not come up with thought experiments for string theory.
First, we should ask what a thought experiment is? Let us say that it is a mental exercise where you test a hypothesis in your mind and try to work out what that hypothesis implies.
One can probably do this with string theory. I would concede that given a lot of physicists do not know what string theory really means, it would be hard for them to figure out what it implies. But, I suppose it is at least conceivable that they might be able to do so.
But, the real question is, of what use is this? And what does it prove?
Well, I suppose it would be nice to know what string theory implies, whether or not that implication is useful, well one would hope so. Perhaps that implication suggests string theory is absurd or cannot be tested or perhaps it can be tested in this way.
But, what would the thought experiment prove? Nothing in itself. One still has to go out and test whatever they figure out with their thought experiment. While they might figure out some useful ideas, they are still doing science and they need to test those ideas.
So, a thought experiment is not a substitute for performing actual experiments. But, that is not to say that thought experiments cannot be useful. They can be, if you figure out the implications of your hypothesis that you can then verify one way or another.
Perhaps we should first ask “What are the laws of physics?”
They are not some magical rules written into the fabric of reality which makes things act the way we observe. No, that is a very Platonic kind of view.
What we are really talking about here is that things always act according to their nature and that they cannot act in any other way. Under normal conditions on Earth, a balloon will float upwards, a brick will fall if you drop it from a height and so forth.
When we talk about, say the “law” of gravity, we are not talking about some rule written into the universe which things somehow know to obey. It simply refers to the fact that things subject to gravity act in certain ways.
They act that way because that is their nature and they have to behave that way. To not do so would be a violation of their nature, which is not possible.
The term “law” simply describes (or approximates) what will happen with certain entities in a given context.
When we talk about the “laws of electromagnetism”, we are referring to the fact that given that the electromagnetic field exists, things subject to it must act in this way. They must, since it is in their nature to react to the electromagnetic field in this way.
So, given that the laws of nature are just things acting according to their nature, is it possible that in some part of the universe the laws of physics are not the same?
Well, we should remember that we are talking about things acting according to their nature. But, this is contextual. Meaning, that things will act as they should, but how they should depends on the context.
It depends on the nature of the entities involved, what the nature of other relevant entities are and how they interact.
If you take one entity, it might have a different nature and therefore act differently to a particular entity.
If you take entity A and it interacts with entity B, a different thing might happen than if A interacts with entity C.
The nature of what happens depends on the context.
But, in the same context, the same thing will always happen in every part of the universe.
Let’s suppose you have entities A and B in location C and they take action D. If the same entities do the same thing in location E, then all else being the same, the same things will happen.