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arXiv · 1108.6280

Maximum edge-cuts in cubic graphs with large girth and in random cubic graphs

Frantisek Kardos·Daniel Kral·Jan Volec
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Abstract

We show that for every cubic graph G with sufficiently large girth there exists a probability distribution on edge-cuts of G such that each edge is in a randomly chosen cut with probability at least 0.88672. This implies that G contains an edge-cut of size at least 1.33008n, where n is the number of vertices of G, and has fractional cut covering number at most 1.127752. The lower bound on the size of maximum edge-cut also applies to random cubic graphs. Specifically, a random n-vertex cubic graph a.a.s. contains an edge cut of size 1.33008n.

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Frantisek Kardos, Daniel Kral, Jan Volec. 2012-07-31. Maximum edge-cuts in cubic graphs with large girth and in random cubic graphs. https://doi.org/10.1002/rsa.20471

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