https://hackerpaper.kaipfister.de/p/1110.2230/Collected HN comments and submissions linking this paper.enMon, 02 Nov 2026 11:16:22 GMThttps://news.ycombinator.com/item?id=38118507urn:hackerpapers:mention:1110.2230:38118507Thu, 02 Nov 2023 19:09:14 GMT<p>Generally, when we talk about the halting problem in the Busy Beaver context, we&#x27;re talking about the halting problem starting from an empty tape. However, some authors have analyzed the behavior of Turing machines on certain classes of infinite tapes. For instance, in [0], the authors surveyed the behavior of TMs starting on a tape with an arbitrary word in the middle, and an infinitely repeating word on one or both sides; one finding is that no 2-state 2-symbol TM is a universal Turing machine, for any of these input tapes. [0] https://arxiv.org/abs/1110.2230</p><p><a href="https://hackerpaper.kaipfister.de/p/1110.2230/">Paper and discussion history</a>. A mention is not an endorsement.</p>cs.CC