Pebbling Arguments for Tree Evaluation

David Liu

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arXiv · 1311.0293

Pebbling Arguments for Tree Evaluation

David Liu

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Abstract

The Tree Evaluation Problem was introduced by Cook et al. in 2010 as a candidate for separating P from L and NL. The most general space lower bounds known for the Tree Evaluation Problem require a semantic restriction on the branching programs and use a connection to well-known pebble games to generate a bottleneck argument. These bounds are met by corresponding upper bounds generated by natural implementations of optimal pebbling algorithms. In this paper we extend these ideas to a variety of restricted families of both deterministic and non-deterministic branching programs, proving tight lower bounds under these restricted models. We also survey and unify known lower bounds in our "pebbling argument" framework.

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BibTeX RIS

David Liu. 2013-11-01. Pebbling Arguments for Tree Evaluation. https://arxiv.org/abs/1311.0293

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