## Touching Graphs of Unit Balls
Hlinený, Petr
(1998)
Full text not available from this repository. ## AbstractThe touching graph of balls is a graph that admits a representation by non-intersecting balls in the space (of prescribed dimension), so that its edges correspond to touching pairs of balls. By a classical result of Koebe [5], the disc touching graphs are exactly the planar graphs. This paper deals with a recognition of unit-ball touching graphs. The 2-dimensional case was proved to be NP-hard by Breu and Kirkpatrick [1]. We show in this paper that also unit-ball touching graphs in dimensions 3 and 4 are NP-hard to recognize. By a recent result of Kirkpatrick and Rote, these results may be transferred in ball-touching graphs in one dimension higher.
Repository Staff Only: item control page References |