Pseudodeterminism and MA != NP^BPP in Communication Complexity

Thomas Watson

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arXiv · 2608.26425

Pseudodeterminism and MA != NP^BPP in Communication Complexity

Thomas Watson

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Abstract

We prove an exponential separation between zero-sided-error randomized and two-sided-error pseudodeterministic communication complexities of partial boolean functions. This qualitatively improves and simplifies the proof of the separation by G\"o\"os, Harms, Riazanov, Sofronova, Sokolov, and Yuan (STOC 2026), which had a two-sided-error randomized upper bound. Then, we generalize our technique to separate the communication complexity analogues of MA and NP^BPP.

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Thomas Watson. 2026-08-26. Pseudodeterminism and MA != NP^BPP in Communication Complexity. https://arxiv.org/abs/2608.26425

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