Some mathematical links on the web
Logic
-About the axiom of choice:
-Foundations of mathematics:
-
Metamath: A proof checker
which allows you to define your formal system, and to code your proofs
inside this formal system. There is also a big file for set-theory (set.mm),
with mechanised proofs of first theorems in set-theory. The program also
gives the list of the axioms which are needed in the proofs that are checked.
So, if you run this program with the file set.mm, your computer will tell
you when the axiom of choice is used in the file set.mm. For example, your
computer will show you that the following things are provable in ZF (set-theory
without choice): existence of uncountable ordinals, construction of the
real numbers, transfinite recursion, ...
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Sylvain Poirier's home page:
Set Theory and Foundations of Mathematics.
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Serge Burckel's home page:
Works in Mathematics and Computer science.
-Logic in general:
Analysis:
General interest: