Eigenvalues and expanders

  title={Eigenvalues and expanders},
  author={Noga Alon},
  • N. Alon
  • Published 2 January 1986
  • Computer Science, Mathematics
  • Combinatorica
Linear expanders have numerous applications to theoretical computer science. Here we show that a regular bipartite graph is an expanderif and only if the second largest eigenvalue of its adjacency matrix is well separated from the first. This result, which has an analytic analogue for Riemannian manifolds enables one to generate expanders randomly and check efficiently their expanding properties. It also supplies an efficient algorithm for approximating the expanding properties of a graph. The… 
Recent progress in combinatorial random matrix theory
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Recent progress in combinatorial random matrix theory
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    Proceedings of 1993 IEEE 34th Annual Foundations of Computer Science
  • 1993
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