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https://en.wikipedia.org/wiki/Zermelo%E2%80%93Fraenkel_set_theory https://en.wikipedia.org/wiki/Zermelo%E2%80%93Fraenkel_set_t... : > Today, Zermelo–Fraenkel s
by westurner 3y ago
https://en.wikipedia.org/wiki/Zermelo%E2%80%93Fraenkel_set_theory https://en.wikipedia.org/wiki/Zermelo%E2%80%93Fraenkel_set_t... :
> Today, Zermelo–Fraenkel set theory [ZFC], with the historically controversial axiom of choice (AC) included, is the standard form of axiomatic set theory and as such is the most common foundation of mathematics.
Foundation of mathematics: https://en.wikipedia.org/wiki/Foundations_of_mathematics https://en.wikipedia.org/wiki/Foundations_of_mathematics
Implementation of mathematics in set theory: https://en.wikipedia.org/wiki/Implementation_of_mathematics_in_set_theory https://en.wikipedia.org/wiki/Implementation_of_mathematics_... :
> The implementation of a number of basic mathematical concepts is carried out in parallel in ZFC (the dominant set theory) and in NFU, the version of Quine's New Foundations shown to be consistent by R. B. Jensen in 1969 (here understood to include at least axioms of Infinity and Choice).
> What is said here applies also to two families of set theories: on the one hand, a range of theories including Zermelo set theory near the lower end of the scale and going up to ZFC extended with large cardinal hypotheses such as "there is a measurable cardinal"; and on the other hand a hierarchy of extensions of NFU which is surveyed in the New Foundations article. These correspond to different general views of what the set-theoretical universe is like
IEEE-754 specifies that float64s have ±infinity and specify ZeroDivisionError. Symbolic CAS with MPFR needn't be limited to float64s.
HoTT in CoQ: Coq-HoTT: https://github.com/HoTT/Coq-HoTT https://github.com/HoTT/Coq-HoTT
What is the relation between Coq-HoTT & Homotopy Type Theory and Set Theory with e.g. ZFC?
Homotopy Type Theory: https://en.wikipedia.org/wiki/Homotopy_type_theory https://en.wikipedia.org/wiki/Homotopy_type_theory :
> "Cartesian Cubical Computational Type Theory: Constructive Reasoning with Paths and Equalities" (2018)
https://scholar.google.com/scholar?cites=9763697449338277760&as_sdt=5,43&sciodt=0,43&hl=en https://scholar.google.com/scholar?cites=9763697449338277760... and sorted by date: https://scholar.google.com/scholar?hl=en&as_sdt=5,43&sciodt=0,43&cites=9763697449338277760&scipsc=&q=&scisbd=1 https://scholar.google.com/scholar?hl=en&as_sdt=5,43&sciodt=...
What does Mathlib have for SetTheory, ZFC, NFU, and HoTT?
leanprover-community/mathlib4//
Mathlib/SetTheory:
https://github.com/leanprover-community/mathlib4/tree/master/Mathlib/SetTheory https://github.com/leanprover-community/mathlib4/tree/master...
- JonChesterfield 3y agoHomotypy is a constructive one. It drops the assumption that any given proposition is either true or false, on the grounds that lots of propositions are undecidable and that's fine. A consequence of no law of the excluded middle (the p or ~p one) is no axiom of choice, so ZFC isn't going to be compatible with it, but ZF probably is. Personally I'm convinced constructive maths is the right choice and will cheerfully abandon whatever wonders the axiom of choice provides to mathematics, because I'm not a mathematician and I care about computable functions.
- westurner 3y agoFrom https://news.ycombinator.com/item?id=37430759#37441973 https://news.ycombinator.com/item?id=37430759#37441973 : > Do any existing CAS systems have configurable axioms? OTOH: Conway's surreal infinities, Do not early eliminate terms next to infinity, Each instance of infinity might should have a unique identity, configurable Order of operations," Optional Axiom of Choice, Complex Wave functions: https://en.wikipedia.org/wiki/Wave_function https://en.wikipedia.org/wiki/Wave_function , Quantum logic, https://news.ycombinator.com/item?id=37367951#37379123 https://news.ycombinator.com/item?id=37367951#37379123 : > [...] is it ever shown that Quantum Logic is indeed the correct and sufficient logic for propositional calculus and also for all physical systems? ( Quantum statistical mechanics: https://en.wikipedia.org/wiki/Quantum_statistical_mechanics https://en.wikipedia.org/wiki/Quantum_statistical_mechanics ) Quantum logic > Relationship to other logics: https://en.wikipedia.org/wiki/Quantum_logic#Relationship_to_other_logics https://en.wikipedia.org/wiki/Quantum_logic#Relationship_to_...