The number of guards needed by a museum: A phase transition in vertex covering of random graphs
نویسندگان
چکیده
In this Letter we study the NP-complete vertex cover problem on finite connectivity random graphs. When the allowed size of the cover set is decreased, a discontinuous transition in solvability and typical-case complexity occurs. This transition is characterized by means of exact numerical simulations as well as by analytical replica calculations. The replica symmetric phase diagram is in excellent agreement with numerical findings up to average connectivity e, where replica symmetry becomes locally unstable.
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عنوان ژورنال:
- Physical review letters
دوره 84 26 Pt 1 شماره
صفحات -
تاریخ انتشار 2000