### Abstract

We present an efficient algorithm to find a good solution to the Unique Games problem when the constraint graph is an expander. We introduce a new analysis of the standard SDP in this case that involves correlations among distant vertices. It also leads to a parallel repetition theorem for unique games when the graph is an expander.

Original language | English (US) |
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Title of host publication | STOC'08 |

Subtitle of host publication | Proceedings of the 2008 ACM Symposium on Theory of Computing |

Pages | 21-28 |

Number of pages | 8 |

State | Published - Dec 8 2008 |

Event | 40th Annual ACM Symposium on Theory of Computing, STOC 2008 - Victoria, BC, Canada Duration: May 17 2008 → May 20 2008 |

### Publication series

Name | Proceedings of the Annual ACM Symposium on Theory of Computing |
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ISSN (Print) | 0737-8017 |

### Other

Other | 40th Annual ACM Symposium on Theory of Computing, STOC 2008 |
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Country | Canada |

City | Victoria, BC |

Period | 5/17/08 → 5/20/08 |

### All Science Journal Classification (ASJC) codes

- Software

### Keywords

- Approximation algorithms
- Expander graphs
- Semidehmte programming

## Cite this

Arora, S., Steurer, D., Knot, S. A., Tulsiani, M., Kolla, A., & Vishnoi, N. K. (2008). Unique games on expanding constraint graphs are easy. In

*STOC'08: Proceedings of the 2008 ACM Symposium on Theory of Computing*(pp. 21-28). (Proceedings of the Annual ACM Symposium on Theory of Computing).