Temporal Graph Classes: A View Through Temporal Separators

  • Till Fluschnik
  • Hendrik Molter
  • Rolf Niedermeier
  • Philipp ZschocheEmail author
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 11159)


We investigate the computational complexity of separating two distinct vertices s and z by vertex deletion in a temporal graph. In a temporal graph, the vertex set is fixed but the edges have (discrete) time labels. Since the corresponding Temporal (sz)-Separation problem is NP-hard, it is natural to investigate whether relevant special cases exist that are computationally tractable. To this end, we study restrictions of the underlying (static) graph—there we observe polynomial-time solvability in the case of bounded treewidth—as well as restrictions concerning the “temporal evolution” along the time steps. Systematically studying partially novel concepts in this direction, we identify sharp borders between tractable and intractable cases.


Temperature Graph Special Graph Classes Polynomial-time Solvability Unit Interval Graphs Underlying Graph 
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Copyright information

© Springer Nature Switzerland AG 2018

Authors and Affiliations

  • Till Fluschnik
    • 1
  • Hendrik Molter
    • 1
  • Rolf Niedermeier
    • 1
  • Philipp Zschoche
    • 1
    Email author
  1. 1.Institut für Softwaretechnik und Theoretische InformatikTU BerlinBerlinGermany

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