Strength and limitations of Sherali-Adams and Nullstellensatz proof systems

We compare the strength of the algebraic proof systems Sherali-Adams (SA) and Nullstellensatz (NS) with Frege-style proof systems. Unlike bounded-depth Frege, SA has polynomial-size proofs of the pigeonhole principle (PHP). A natural question is whether adding PHP to bounded-depth Frege is enough to...

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Detalles Bibliográficos
Autores: Bonacina, Ilario|||0000-0002-5697-8070, Bonet Carbonell, M. Luisa|||0000-0003-1646-7177
Tipo de recurso: artículo
Fecha de publicación:2024
País:España
Institución:Universitat Politècnica de Catalunya (UPC)
Repositorio:UPCommons. Portal del coneixement obert de la UPC
Idioma:inglés
OAI Identifier:oai:upcommons.upc.edu:2117/421056
Acceso en línea:https://hdl.handle.net/2117/421056
https://dx.doi.org/10.1016/j.apal.2024.103538
Access Level:acceso abierto
Palabra clave:Bounded-depth Frege
Nullstellensatz
Sherali-Adams
Pigeonhole principle
Àrees temàtiques de la UPC::Informàtica::Informàtica teòrica
Descripción
Sumario:We compare the strength of the algebraic proof systems Sherali-Adams (SA) and Nullstellensatz (NS) with Frege-style proof systems. Unlike bounded-depth Frege, SA has polynomial-size proofs of the pigeonhole principle (PHP). A natural question is whether adding PHP to bounded-depth Frege is enough to simulate SA. We show that SA, with unary integer coefficients, lies strictly between tree-like depth-1 Frege + PHP and tree-like Resolution. We introduce a levelled version of PHP (L PHP) and we show that SA with integer coefficients lies strictly between tree-like depth-1 Frege + L PHP and Resolution. Analogous results are shown for NS using the bijective (i.e. onto and functional) pigeonhole principle and a leveled version of it.