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arXiv · 1512.05411

Non-Local Probes Do Not Help with Graph Problems

Mika Göös·Juho Hirvonen·Reut Levi·Moti Medina·Jukka Suomela
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Abstract

This work bridges the gap between distributed and centralised models of computing in the context of sublinear-time graph algorithms. A priori, typical centralised models of computing (e.g., parallel decision trees or centralised local algorithms) seem to be much more powerful than distributed message-passing algorithms: centralised algorithms can directly probe any part of the input, while in distributed algorithms nodes can only communicate with their immediate neighbours. We show that for a large class of graph problems, this extra freedom does not help centralised algorithms at all: for example, efficient stateless deterministic centralised local algorithms can be simulated with efficient distributed message-passing algorithms. In particular, this enables us to transfer existing lower bound results from distributed algorithms to centralised local algorithms.

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Mika Göös, Juho Hirvonen, Reut Levi, Moti Medina, Jukka Suomela. 2015-12-16. Non-Local Probes Do Not Help with Graph Problems. https://arxiv.org/abs/1512.05411

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