Cutting Planes and the Parameter Cutwidth

  • Authors:
  • Stefan Dantchev;Barnaby Martin

  • Affiliations:
  • Department of Computer Science, University of Durham, Science Labs, Durham, U.K. DH1 3LE;Équipe de Logique Mathématique - CNRS UMR 7056, Université Paris 7, UFR de Mathématiques - case 7012, site Chevaleret, Paris Cedex 13, France 75205

  • Venue:
  • CiE '09 Proceedings of the 5th Conference on Computability in Europe: Mathematical Theory and Computational Practice
  • Year:
  • 2009

Quantified Score

Hi-index 0.00

Visualization

Abstract

We introduce the parameter cutwidth for the Cutting Planes (CP ) system of Gomory and Chvátal. We provide linear lower bounds on cutwidth for two simple polytopes. Considering CP as a propositional refutation system, one can see that the cutwidth of a CNF contradiction F is always bound above by the Resolution width of F . We provide an example proving that the converse fails: there is an F which has constant cutwidth, but has Resolution width ***(n ). Following a standard method for converting an FO sentence *** , without finite models, into a sequence of CNFs, F *** ,n , we provide a classification theorem for CP based on the sum cutwidth plus rank. Specifically, the cutwidth+rank of F *** ,n is bound by a constant c (depending on *** only) iff *** has no (infinite) models. This result may be seen as a relative of various gap theorems extant in the literature.