PlanetPhysics/Quantum Logic

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This is a contributed topic on quantum logic using tools available on the internet.

Quantum Logic description
There are several approaches to quantum logic, and it should be therefore more appropriately called `Quantum Logics'. The following is a short list of such approaches to quantum logics.


 * A standard approach to quantum logics is to add axioms so that it can be treated as a theory of Hilbert lattices . Both Hilbert lattices and Hilbert space are involved in the foundation of quantum mechanics, and they are considered to be `dual' to each other. "Just as Fourier transforms have led to greater insight into the nature of electrical signals, it may be possible that (via Sol\`er's theorem) quantum logic and Hilbert lattices will lead to new results in quantum mechanics." The axioms of this standard version of quantum logic (QL) can be specified as three distinct groups of axioms:   #
 * the ortholattice axioms: ax-a1 to ax-a5, and ax-r1, ax-r2, ax-r4, ax-r5 ; for example: ax-a1 is: $$a= N(Na)= NNa $$, where N stands for the logical negation; ax-a2 and ax-a3 are respectively the commutativity and associativity axioms; the ax-r1 ro ax-r5 axioms are implication axioms, such as: $$[a =b] \Rightarrow  [b=a] $$ for ax-r1.  #
 * the orthomodular law, ax-r3, that holds for those ortholattices that are also orthomodular lattices: $$1= [a \equiv b] \Rightarrow [a=b];$$ (interestingly, without ax-r3, the quantum logic becomes decidable), and  #
 * stronger axioms than 1. and 2. for orthomodular lattices that are also Hilbert lattices.      The set of closed subspaces of a Hilbert space, $$\mathcal{C}_H$$ determines a special case of an orthomodular lattice $$\left\langle{\mathcal{A},\cup, N}\right\rangle$$.
 * An interesting system for further studies is that in which the orthomodular lattice axiom or `orthomodular law', ax-r3, is replaced by a weaker axiom called the weakly orthomodular (WOM) law ;
 * Quantum propositional calculus : quantum logic can be expressed and studied as a propositional calculus but involving the axioms or rules of quantum logics instead of those of Boolean logic. Quantum propositional calculus (QPC) is based on the algebra(s) of orthomodular lattices, similarly to the foundation of classical propositional calculus (CPC) on Boolean algebras. However, one notes that classical propositional calculus can also be modeled by a non-Boolean lattice, such as a centered $$LM_n$$-logic algebra. Another remarkable example is that of the logic lattice $$O6$$ ([0, a, b, Na, Nb,1]) which is a non-distributive model for classical propositional calculus.
 * A second approach preferred by logicians is to define quantum logics via many-valued (MV) logic algebras such as the \L{}ukasiewicz-Moisil n-valued logic algebras.