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Is the spin in quantum entanglement set the moment the particles are separated, instead of transmitted instantaneously to its twin particle at the time of measurement? Wouldn't this make more sense then particles transmitting information instantly across a large distance faster than the speed of light? Couldn't the superposition collapse at the time of separation leaving both particles frozen with the same spin, momentum, polarization, ect no matter where they are taken or what happens to them?

Could this tie in with "Can Quantum-Mechanical Description of Physical Reality Be Considered Complete' ? A. Einstein, B. Podolsky AND N. Rosen, Institute for Advanced Study, Princeton, New Jersey (Received March 25, 1935) ".

I very well could be something I'm missing, I don't have a degree in Quantum Physics, yet, and I'm only a Senior in High School, but Quantum Physics is something that I am very interested in. I have had this question for a few years now, and have not found anything on the subject. Now I am writing a research paper on the subject for an English class, but I can't find anything directly mentioning my question.

One fault in my research could be the fact that I do not understand much of the math, due to my level being Calculus, but I would really like this answered. It would be great if I could get a link to the research or proof against or for my argument.

Norbert Schuch
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Clint
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Is the spin in quantum entanglement set the moment the particles are separated...?

If this is asking whether the outcomes of eventual spin-measurements are predetermined at the moment the particles are separated, then the answer is no. We know this because (for example) the CHSH inequality is violated in the real world. The CHSH inequality is reviewed in detail in an another post: https://physics.stackexchange.com/a/438137/206691. It doesn't use any quantum theory at all, and the math is relatively easy. That same post also lists a few references about experiments demonstrating that this seemingly-unviolatable inequality really is violated in the real world. (The CHSH inequality is one of the simplest examples of a Bell inequality.)

...transmitted instantaneously to its twin particle at the time of measurement...

Quantum theory accounts for the observed results without invoking any kind of faster-than-light communication. In fact, the impossibility of faster-than-light communication is built into the general principles of quantum field theory, which is the foundation for our current understanding of all non-gravitational phenomena. Quantum field theory is designed to respect the constraints of special relativity, and it correctly predicts the observed results in experiments with entangled particles.

Quantum theory manages to predict the results of such experiments without using either pre-determined measurement outcomes or faster-than-light communication, and the way it achieves this is interesting. I don't have a clear-and-concise-and-nonmathematical way to describe how quantum theory does this. However, learning about the CHSH inequality and its real-world violations is a great place to start, because these things can be learned independently of quantum theory, and they will help build a better appreciation for why something like quantum theory is needed.

Chiral Anomaly
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To be fair, we must clarify that Dan Yand answer is implicitly assuming locality, that is, that it is not possible that quantum mechanics is the result of local hidden variables that have determined values. By "local" we mean that the laws that govern the interactions of these hidden variables do not have an "action at a distance" (https://en.wikipedia.org/wiki/Action_at_a_distance"). However it has been shown (https://en.wikipedia.org/wiki/De_Broglie%E2%80%93Bohm_theory) that if you allow non-local interactions, the state of the system could be in a definite state in the sense you meant.