I'm an amateur python coder and I've built most if not all of my learning on picking up pieces that work for the immediate task at hand. Years later, I write code that Works Fine but since I never had a traditional education in python itself it feels makeshift and janky. I was very late to learning relatively deeper concepts (and even simple-ish ones like OOP) as a result.
Now I want to learn Julia and Rust, and I want to avoid making the same mistakes again. Is reading books really the gold standard for learning a paradigm? Additional advice is also welcome.
Using PSPACE-completeness of quantified boolean logic Valerii Sopin claimed to have obtained that PH = PSPACE, see https://arxiv.org/abs/1411.0628
True quantified Boolean formula is indeed a generalisation of the Boolean Satisfiability Problem, where determining of interpretation that satisfies a given Boolean formula is replaced by existence of Boolean functions that makes a given QBF to be tautology. Such functions are called the Skolem functions.
The essential idea of the proof is to skolemize, and then use additional formulas from the second level of the polynomial hierarchy inside the skolemized prefix to enforce that the skolem variables indeed depend only on the universally quantified variables they are supposed to. However, some dependence is lost when the quantification is reversed. It is called "XOR issue" because the functional dependence can be expressed by means of an XOR formula. Thus, it is needed to locate these XORs, but there is no need to locate all chains with XORs: any chain includes a XOR of only two variables. The last can be done locally in each iteration (keep in mind the algebraic normal form (ANF)), when all arguments are specified.
Relativization is defeated due to the well-known fact: PH = PSPACE iff second-order logic over finite structures gains no additional power from the addition of a transitive closure operator. Boolean algebra is finite. The exchange is possible due to finite possibilities for arguments. So, the theorems with oracles are not applicable since a random oracle is an arbitrary set. And that’s why Polynomial Hierarchy is infinite relative to a random oracle with probability 1.
So from what I have read during the TLS exchange a symmetric key is made which used for both encryption and decryption of data, my question is, how is this key exchanged without allowing someone in the middle to grab it? is the key generated on both server and client and both just come to the same conclusion on what that key is based on information they got during the handshake and if so how are those secrets shared securely