Refuting Tianrong Lin's arXiv:2110.05942 "Resolution of The Linear-Bounded Automata Question"

Thomas Preu

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arXiv · 2110.12421

Refuting Tianrong Lin's arXiv:2110.05942 "Resolution of The Linear-Bounded Automata Question"

Thomas Preu

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Abstract

In the preprint mentioned in the title Mr. Tianrong claims to prove $\textrm{NSPACE}[n]\neq\textrm{DSPACE}[n]$, resolving a longstanding open problem in automata theory called the LBA question. He claims to achieve this by showing more generally $\textrm{NSPACE}[S(n)]\neq\textrm{DSPACE}[S(n)]$ for suitable $S(n)$. We demonstrate that his proof is incomplete, even wrong, and his strategy cannot be repaired. Update to include recent developments of Mr. Tianrong's preprint.

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Thomas Preu. 2021-10-24. Refuting Tianrong Lin's arXiv:2110.05942 "Resolution of The Linear-Bounded Automata Question". https://arxiv.org/abs/2110.12421

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