Comments
These are comments on the effort to derive physics from logic as described here.
There is hesitation among some people to accept any attempt to derive physics from logic. There are objections based on such attempts not being "science" as they understand it. And there are objections based on the incompleteness of mathematics. The claim is that science is a process of producing theories that predict events that can be confirmed by experiment, and the data gained from experiment can be used to refine theories. But theories based on logic alone bypass data and experimental confirmation and so cannot be science. This perspective might make it difficult to publish derivations from logic in the physics department; they might say such efforts belong more in the philosophy or math department. And those departments might say it has more to do with physics. But if such a derivation has a good chance at producing a valid theory, all departments should be concerned. And since it concerns the ultimate justification of physics, I would think it should belong in the physic department.
A derivation from logic alone does not exclude confirmation from experiment. Confirmation would certainly be welcome, but it would not be a surprise, since it would be an undeniable conclusion. If logic predicted certain events that experiment proved did not occur, then logic itself would be held suspect, and we would have no reliable means to believe anything. Meaning and purpose itself would lose all value. And the discomfort over this possibility probably causes some to hesitate. But to think that logical reason does not have the final authority about reality can be equally distressing.
A derivation from logic differs from the usual in that it does not start with data from any particular observation, but it starts with the most general of principles. It is possible, however, to view logic as the first physical theory. The ancient philosophers used physical situations as the premises to conclude the existence of other physical situations. Later this was generalized to cause and effect, and later to premise and conclusion of abstract argumentation. The ability of logic to make conclusions was then used to deduce the truth and falsity of purely abstract constructions such as mathematics. It is this ability of logic to apply equally well to the abstract as well as the concrete, to fiction as well as to fact, that makes some think that physics cannot be derived from logic. You'd never know whether you're deriving fact or fiction. But just like every other theory of physics, the laws would only tell you what type of results are possible if the right experiment is set up; they don't tell us that the experiment will be set up.
For most scientists physical circumstances always remain a contingency in the equations of logic - a proposition, describing reality, whose truth or falsity is not ascribed, but whose consequence follow if it is true. It is claimed the ancient Greeks failed in their attempt to derive everything from logic, and it should not be attempted now. But the ancient Greeks failed because everything remained a contingency in their logic. But whatever is a contingency remains by definition unexplained because a contingency is not something whose existence is necessarily asserted as true. Stating a theory that given these physical circumstances as a premise these conclusions must follow as a result does not say that the premises are required; it does not give reason why the premise must exist. The only way to explain everything is that everything derives from reason itself. A theory of everything (TOE) cannot exist except as a derivation from logic. Otherwise, if physical entities are contingent on other entities which themselves are contingent on something else, etc, then your theory rests on a contingent fact which has no further explanation.
Theorists must face the dilemma that theory will ultimately not be able to be confirmed by experiment. For it would take all the energy in the universe to create an experiment to confirm a theory of how the universe was created. There is no choice but to build a TOE on principle alone. It only remains to be seen on what principles to rely on. Since logic is based on the algebra of true and false, and since theory must ultimately be true or false, logic has to be the ultimate basis of the ultimate theory.
This effort is not finished and may take some time to complete. In the mean time, I have a TO-DO list, outlining areas that need more attention. Perhaps some readers might have comments and suggestions along these lines of thinking. Contact information is on that page.