Games with backtracking options corresponding to the ordinal analysis of $PA$

Autor: Ken, Eitetsu
Rok vydání: 2024
Předmět:
Druh dokumentu: Working Paper
Popis: We give another proof of ordinal analysis of $I\Sigma_{k}$-fragments of Peano Arithmetic which is free from cut-elimination of $\omega$-logic. Our main tool is a direct witnessing argument utilizing game notion, motivated from the realm of proof complexity and bounded arithmetic.
Comment: 36 pages, figures added, Corollary 4.13 added, revisiting characterization of provably total recursive functions of I\Sigma_k and that of dynamic ordinal analysis are removed for simplicity, presentation improved
Databáze: arXiv