# Michael R. Capalbo

• IEEE Conference on Computational Complexity
• 2002
The main concrete result of this paper is the first explicit construction of constant degree <i>lossless</i> expanders. In these graphs, the expansion factor is almost as large as possible: (1&#8212;&#949;)<i>D</i>, where <i>D</i> is the degree and &#949; is an arbitrarily small constant. The best previous explicit constructions gave expansion factor D/2,(More)
• Random Struct. Algorithms
• 2007
Let H be a family of graphs. A graph T is H-universal if it contains a copy of each H ∈ H as a subgraph. Let H(k, n) denote the family of graphs on n vertices with maximum degree at most k. For all positive integers k and n, we construct an H(k, n)-universal graph T with Ok(n 2 k log 4 k n) edges and exactly n vertices. The number of edges is almost as(More)
• SODA
• 2008
Let <i>H</i> be a finite family of graphs. A graph <i>G</i> is <i>H</i>-universal if it contains a copy of each <i>H</i> &#8712; <i>H</i> as a subgraph. Let <i>H</i><i>(k,n)</i> denote the family of graphs on <i>n</i> vertices with maximum degree at most <i>k.</i> For all admissible <i>k</i> and <i>n</i>, we construct an <i>H</i><i>(k, n)</i>-universal(More)
• SODA
• 2003
We present an explicit construction of an infinite family of <i>N</i>-superconcentrators of density 44. The most economical previously known explicit graphs of this type have density around 60.
For any positive integers and , let denote the family of graphs on vertices with maximum degree , and let denote the family of bipartite graphs on vertices with vertices in each vertex class, and with maximum degree . On one hand, we note that any -universal graph must have edges. On the other hand, for any , we explicitly construct -universal graphs and on(More)
• RANDOM-APPROX
• 2001
Let H be a family of graphs. We say that G is H-universal if, for each H ∈ H, the graph G contains a subgraph isomorphic to H. Let H(k, n) denote the family of graphs on n vertices with maximum degree at most k. For each fixed k and each n sufficiently large, we explicitly construct an H(k, n)-universal graph Γ (k, n) with O(n(log n)) edges. This is optimal(More)
• FOCS
• 2002
We present a simple, explicit construction of an infinite family F of bounded-degree ’unique-neighbor’ expanders Γ; i.e., there are strictly positive constants α and , such that all Γ = (X,E(Γ)) ∈ F satisfy the following property. For each subset S of X with no more than α|X| vertices, there are at least |S| vertices in X \ S that are adjacent in Γ to(More)
• 48th Annual IEEE Symposium on Foundations of…
• 2007
We describe a deterministic, polynomial time algorithm for finding edge-disjoint paths connecting given pairs of vertices in an expander. Specifically, the input of the algorithm is a sufficiently strong d-regular expander G on n vertices, and a sequence of pairs s<sub>i</sub>, t<sub>i</sub> (1lesilesr) of vertices, where, r=Theta(nd log d/log n), and no(More)
Pseudorandomness is the theory of efficiently generating objects that “look random” despite being constructed using little or no randomness. This survey of the subject places particular emphasis on the intimate connections that have been discovered between a variety of fundamental “pseudorandom objects” that at first seem very different in nature: expander(More)