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The general enterprise of calibrating the strength of classical mathematical theorems in terms of the axioms, typically of set existence, needed to prove them; originated in its modern form in the 1970s by H. Friedman and S. G. Simpson (see R.A. Shore, "Reverse Mathematics: The Playground of Logic", 2010).

6 votes
Accepted

Formal definition of arithmetic transfinite recursion

To repeat Emil and Andreas's comments, it can be found in Stephen G. Simpson, "Systems of Second-Order Arithmetic", the first chapter of which is available here: http://www.personal.psu.edu/t20/sosoa …
Jason Rute's user avatar
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1 vote

Proving moduli of uniform continuity in RCA_0

On a space like $\mathbb{R}^n$, $[0,1]^n$, or $\mathbb{C}$, every uniformly continuous function that "arises in practice" (more on this in a bit) has a computable modulus of continuity. To find examp …
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7 votes
Accepted

reverse mathematics strength of "Lipschitz functions are somewhere differentiable"

(Update: I made my answer clearer and also fixed the references and added more.) Your theorem should be true in every $\omega$-model of $\mathsf{RCA}_0$ as follows. The following paper Brattka, Mil …
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4 votes

Understanding the nature and structure of proofs; Reverse Mathematics and Proof Theory. Prer...

As for your question on prerequisites, the more logic you know the better. Of course the basic concepts---proofs, models, Peano arithmetic, incompleteness, compactness, nonstandard models, primitive …
8 votes
7 answers
648 views

Strength of Bishop style constructive mathematics vs $\mathsf{RCA}_0$

This question came out of this other MO question of mine. My question is Is there a formal comparison between $\mathsf{RCA}_0$ and $\mathsf{BISH}$ (Bishop style constructive mathematics as used in c …
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23 votes
2 answers
2k views

Prospects for reverse mathematics in Homotopy Type Theory

Reverse mathematics, as I mean here, is the study of which theorems/axioms can be used to prove other theorems/axioms over a weak base theory. Examples include Subsystems of Second Order Arithmetic …
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