Atheism and the existence of peanut butter

[polymath257]

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Finally, the notion of causality in your third article is dependent on the existence of natural laws. So, once again, it does not address the fact that ALL causality, such as it exists, is within the universe and a consequence of the natural laws. it does NOT support your claim for causality outside of the universe, nor even the claim of simultaneous causality within the universe.

It does not follow from causality being true inside the universe that it depends on natural laws. Natural laws could simply be the form causality takes inside a spacetime. As I mentioned before, Kant argued that causality is a synthetic a priori,, you can't deduce it from experience. You can't prove that causality is true even within the universe, but you still need it as an assumption to do science. You either accept it as universally true or hypocritically reject it to avoid dealing with the possiblity of a first cause.

Actually, the fact that quantum mechanics is an acausal theory is enough to show that causality is NOT synthetic a priori. In point of fact, I don't think there is asuch a thing as synthetic a priori knowledge. Kant saying something doesn't make it automatically true. In fact, Kant thought that Euclidean space was also synthetic a priori. And now we know that not to be the case.

And the fact that QM is a supreme example of a scientific theory AND is acausal is enough to show that causality isn't required to do science. Just repeatability and testability.

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For example, relativistic causality is the claim that events that are separated by a timelike relativistic separation are uncorrelated. 

I am really curious to know from where you're pulling these definitions exactly? Please supplement your claims with reliable sources.  Relativistic causality means that causal processes or signals can propagate only within the light-cone. This means that causes must precede effects in space-time.

Source: https://www.nature.com/articles/s41467-019-09505-2
Quote: In all relativistic theories, causality is imposed, i.e., the requirement that causes must precede effects in all space–time rest frames.

Source: https://www.researchgate.net/publication..._Causality
Quote: I discuss the idea of relativistic causality i.e. the requirement that causal processes or signals can propagate only within the light-cone.

Correlations are involved at the quantum level, there is absolutely no mention of the word correlation in any textbook treatment of Special Relativity.

Exactly. Special relativity is a non-quantum theory. It is a classical theory. When quantum mechanics is added on, we get quantum field theories. So, in the classical theory, all influences remain in the light cone. In the quantum version, the correlations outside of the light cone are zero.

A good reference is Peskin and Schroeder, 'An Introduction to Quantum Field Theory'. The relevant section is even labeled 'Causality', pp 27-29. Here' the description of causality is that no measurement can affect any other measurement outside of the light cone. How is this achieved? By having the commutator of the fields be zero (no correlation) for events outside of each others light cones.  In order for this to happen, anti-particles must have the same mass as the ordinary particles. this discussion of causality comes up in the determination of the propagator.

Or, if you prefer Nachtman's book 'Elementary Particle Physics', the relevant equations are 3.50, once again describing the commutator of events outside of each others light cones and requiring the commutator be zero. Once again, this means no correlation.

Or, if you prefer Kaku's book, 'Quantum Field Theory', the description of microcausality in section 3.4 once again hinges on the nature of the commutators and thereby the correlations between events separated in a way that light could not travel between them.

Or, if you prefer Weinberg's book, The Quantum Theory of Fields (Vol 1), you can find the same discussion in section 3.5.

In ALL of these, the term 'causality' is used precisely when the events outside of each others light cones have vanishing commutators. In other words, they are uncorrelated.

Are those valid enough sources for you? All are standard texts for graduate physics in this subject (although Kaku's book is pretty poor, frankly).

Now, I don't believe for a second you have actually read/understood anything about quantum field theories that goes beyond the popular treatments. I have. And the notion of causality used in quantum mechanics isn't the type of causality you require for your program. It is a matter of probabilities and correlations and NOT of what is 'necessary' for other events to happen. And yes, it has to do with vanishing commutators outside of light cones, just as I said.