Models of Bounded Arithmetic and variants of Pigeonhole Principle

Fuente: arXiv
Enregistré dans:
Détails bibliographiques
Auteur principal: Narusevych, Mykyta
Format: Preprint
Publié: 2022
Sujets:
Accès en ligne:
Tags: Ajouter un tag
Pas de tags, Soyez le premier à ajouter un tag!
_version_ 1866913256864481280
author Narusevych, Mykyta
author_facet Narusevych, Mykyta
contents We give elementary proof that theory $T^1_2(R)$ augmented by the weak pigeonhole principle for all $Δ^b_1(R)$-definable relations does not prove the bijective pigeonhole principle for $R$. This can be derived from known more general results but our proof yields a model of $T^1_2(R)$ in which $ontoPHP^{n+1}_n(R)$ fails for some nonstandard element $n$ while $PHP^{m+1}_m$ holds for all $Δ^b_1(R)$-definable relations and all $m \leq n^{1-ε}$, where $ε> 0$ is a fixed standard rational parameter. This can be seen as a step towards solving an open question posed by M. Ajtai.
format Preprint
id arxiv_https___arxiv_org_abs_2208_14713
institution arXiv
publishDate 2022
record_format arxiv
spellingShingle Models of Bounded Arithmetic and variants of Pigeonhole Principle
Narusevych, Mykyta
Logic
We give elementary proof that theory $T^1_2(R)$ augmented by the weak pigeonhole principle for all $Δ^b_1(R)$-definable relations does not prove the bijective pigeonhole principle for $R$. This can be derived from known more general results but our proof yields a model of $T^1_2(R)$ in which $ontoPHP^{n+1}_n(R)$ fails for some nonstandard element $n$ while $PHP^{m+1}_m$ holds for all $Δ^b_1(R)$-definable relations and all $m \leq n^{1-ε}$, where $ε> 0$ is a fixed standard rational parameter. This can be seen as a step towards solving an open question posed by M. Ajtai.
title Models of Bounded Arithmetic and variants of Pigeonhole Principle
topic Logic
url https://arxiv.org/abs/2208.14713