https://en.wikipedia.org/wiki/Theory_of_everything
In order for a theory to qualify, it has to have been extensivly tested and have a strong consensus in its favor. It also must explain everything fundamental that is in principle explainable. (It doesn't have to answer philosophical questions like "why is there something rather than nothing", since that may not be answerable.) In other words, there shouldn't be any physics question where we would not know how to compute an answer. (Even if the computation itself would take a very long time.)
There will of course be many emergent phenomena that we still don't have good models for. (e.g. we don't have a good way to predict many chaotic systems, even if we understand the underlying particle physics.)
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Seems obviously false to me. How would such a theory explain why it was that way and not some other.. seems like that would require a further theory
@NathanpmYoung I would not consider such explanation from the final theory necessary. I think Theory of Everything would simply be an algorithm that explains all fundamental phenomena and will never be falsified (because universe really follows it).
But then, of course, it might be difficult to know it will never be falsified and to resolve the question..
@NathanpmYoung So for example theory with 20 parameters that need to be measured qualifies, I would say - it could be some other way, but for our universe it is one particular set.
Will probably happen once the physicists finally move from a mathematical paradigm to a computational one, so they can actually properly explain modeling without weird idealistic assumptions at the bottom of mathematics. In my opinion.
I see some movement already, like Wolfram.
Does "having" it mean that it is a theory that has been proposed, that it is near consensus among scientists, that it is a falsifiable theory with experimental evidence supporting it?
Does it have to explain literally everything, or does it merely have to unify general relativity and quantum mechanics?
What confirmation threshold do you plan to use?
Group of theories that are being worked on (like String Theory)
Single Theory with constants known but not verified yet (like Special Relativity shortly after 1905)
Has made at least one prediction which got experimentally verified and where other theories expected something different
Has been repeatedly tested and verified and become scientific consensus (like Special Relativity nowadays)
I‘d use at least threshold 3, but am curious what you think.
@Nirelsang Has been repeatedly tested and verified and become scientific consensus.
