Skolem’s Problem – On the Border Between Decidability and Undecidability Page 1 Vesa
Halava | Tero Harju | Mika Hirvensalo | Juhani Karhumaki Skolem’s Problem – On the Border …

Formal Languages, Automaton and Numeration Systems presents readers with a review of
research related to formal language theory, combinatorics on words or numeration systems …

2 Two notions of undecidability There are two common senses in which one speaks of
undecidability. 1. Independence from axioms: A single statement is called undecidable if …

Positivity of second order linear recurrent sequences - ScienceDirect Skip to main contentSkip
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Since Cocke and Minsky proved 2-tag systems universal, they have been extensively used
to prove the universality of numerous computational models. Unfortunately, all known …

In this work, we show that very natural, apparently simple problems in quantum
measurement theory can be undecidable even if their classical analogues are decidable …

The interplay between words, computability, algebra and arithmetic has now proved its
relevance and fruitfulness. Indeed, the cross-fertilization between formal logic and finite …

There are several known undecidable problems for 3× 3 integer matrices the proof of which
use a reduction from the Post Correspondence Problem (PCP). We establish new lower …

Several physically inspired problems have been proven undecidable; examples are the
spectral gap problem and the membership problem for quantum correlations. Most of these …

Positivity of third order linear recurrence sequences - ScienceDirect Skip to main contentSkip to
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