I'm writing one. I am formulating curricula for myself to ensure I have the adequate basis of knowledge to avoid the sorts of mistakes that would prevent me from being taken seriously before my ideas are even seriously contended with.
The term “Theory of Everything” (TOE) is defined by physicists as the unification of all four known fundamental forces, electromagnetism, the strong and weak forces, and gravity, into a single comprehensive theory which has “universal applicability”. There is an unfounded ideological commitment to “unification” as the path to ultimate truth in physics, but in the end, there are two problems to that. First, we must recognize that science asks carefully delimited questions about natural phenomena, and if the science is so “selective”, then it cannot claim that its picture of reality is complete, and consequently, the resultant theory cannot reasonably be called a theory of “everything”.
Second, even if we could conjure up a mathematical framework demonstrating that all four forces were derived from a single force in the first moments of the Big Bang, what would we really have accomplished? It wouldn’t be testable, it would do nothing to tell us about the nature of physical reality, and it certainly will not yield the sought after single underlying theoretical framework that governs the universe. At best, it would be a matter of abstract mathematics rather than physics, it would have no real connection to the real world.
what markers should I focus on? one of my main concerns is that if I'm going to attempt to defend the universal applicability of the model, then I must be, in some sense, decently competent at talking about everything. naturally, this presents a profoundly disadvantageous burden for me, such as would likely prevent me from attaining a degree of mastery over one specific domain as would grant me the credentials that many of the actual cultural mover-shakers use to pre-filter the ideas on which they spend their time
What you need to do is define the problem in a way that makes sense, what are you trying to accomplish? A “Theory of Everything” as it is currently defined by physicists would necessarily be a Quantum Theory, and Quantum Theory itself has rendered obsolete the view that the universe is wholly determined by inflexible and universal laws. A “Theory of Everything is fundamentally a belief in the causal closure of the physical world, which necessitates an axiomatic system that is consistent and logically complete and Godel’s proof showed that to be impossible. His Incompleteness Theorem is analytically perfect and rigidly deductive and therefore conclusive as far as logic and science are concerned. It states categorically that no axiomatic system is, or can be, complete without reference to a higher system in which that system must be embedded. Gödel proved that a “Theory of Everything” is therefore impossible, which is to say that it is logically and scientifically impossible to devise a set of axioms from which all the phenomena of the external world can be deduced. Werner Heisenberg confirmed that uncertainty is a feature of reality with his own proof in the physical sciences. Each and every unified theory, which is to say every scientific attempt at unifying and completing physical theory, postulates other dimensions in which this reality is embedded, every one of them, as and perhaps because, Kurt Gödel logically proved that they must.
Beyond the proven impossibility of the task, you need to further consider that any unification of the laws of physics must necessarily take into account the thought/consciousness dimension, and thus must unify physics with psyche as well. You need to determine how you will go about formulating consciousness into the mathematical framework of science, something that has always completely eluded science.
What I think is that reality isn’t a problem that needs to be solved, and I wonder why we think that finite creatures can comprehend the whole, that our finite minds can somehow fully axiomatize an infinitely diverse universe of reality of which we are a mere part.
Maps are not territory, and there are definite limits to our mental powers and our mathematics, and maybe we should get past our arrogance by waking up to the fact that we are finite beings pondering the infinite, and that a part cannot circumscribe the whole.