Algebraic Theory of Promise Constraint Satisfaction Problems, First Steps

Libor Barto

doi:10.1007/978-3-030-25027-0_1

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arXiv · 1909.04871

Algebraic Theory of Promise Constraint Satisfaction Problems, First Steps

Libor Barto

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Abstract

What makes a computational problem easy (e.g., in P, that is, solvable in polynomial time) or hard (e.g., NP-hard)? This fundamental question now has a satisfactory answer for a quite broad class of computational problems, so called fixed-template constraint satisfaction problems (CSPs) -- it has turned out that their complexity is captured by a certain specific form of symmetry. This paper explains an extension of this theory to a much broader class of computational problems, the promise CSPs, which includes relaxed versions of CSPs such as the problem of finding a 137-coloring of a 3-colorable graph.

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Libor Barto. 2019-09-11. Algebraic Theory of Promise Constraint Satisfaction Problems, First Steps. https://doi.org/10.1007/978-3-030-25027-0_1

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