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arXiv · 1008.0225

Separating Bounded Arithmetics by Herbrand Consistency

Saeed Salehi
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Abstract

The problem of $\Pi_1-$separating the hierarchy of bounded arithmetic has been studied in the paper. It is shown that the notion of Herbrand Consistency, in its full generality, cannot $\Pi_1-$separate the theory ${\rm I\Delta_0+\bigwedge_j\Omega_j}$ from ${\rm I\Delta_0}$; though it can $\Pi_1-$separate ${\rm I\Delta_0+Exp}$ from ${\rm I\Delta_0}$. This extends a result of L. A. Ko{\l}odziejczyk (2006), by showing the unprovability of the Herbrand Consistency of ${\rm I\Delta_0}$ in the theory ${\rm I\Delta_0+\bigwedge_j\Omega_j}$.

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Saeed Salehi. 2010-08-02. Separating Bounded Arithmetics by Herbrand Consistency. https://doi.org/10.1093/logcom/exr005

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