• Corpus ID: 58804

# Cohomology in Grothendieck Topologies and Lower Bounds in Boolean Complexity II: A Simple Example

```@article{Friedman2006CohomologyIG,
title={Cohomology in Grothendieck Topologies and Lower Bounds in Boolean Complexity II: A Simple Example},
author={J. Friedman},
journal={ArXiv},
year={2006},
volume={abs/cs/0512008}
}```
• J. Friedman
• Published 1 December 2005
• Mathematics, Computer Science
• ArXiv
In a previous paper we have suggested a number of ideas to attack circuit size complexity with cohomology. As a simple example, we take circuits that can only compute the AND of two inputs, which essentially reduces to SET COVER. We show a very special case of the cohomological approach (one particular free category, using injective and superskyscraper sheaves) gives the linear programming bound coming from the relaxation of the standard integer programming reformulation of SET COVER.
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