Matrix mortality problem: Difference between revisions

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In [[computer science]], the '''matrix mortality problem''' (or '''mortal matrix problem''') is a [[decision problem]] that asks, given a finite set of size ''m'' of ''n''×''n'' matrices with integer coefficients, whether the [[zero matrix]] can be expressed as a finite product of matrices from this set.
 
The matrix mortality problem is known to be [[undecidable problem|undecidable]] when ''n'' ≥ 3{{r|paterson}}. In fact, it is already undecidable for sets of 6
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In the case ''n'' = 2, it is an open problem whether matrix mortality is decidable, but several special cases have been solved: the problem is decidable for sets of 2 matrices{{r|bournez-branicky}}, and for sets of matrices which contain at most one invertible matrix{{r|heckman}}.
{| class="wikitable"
|+The current frontier of knowledge
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==NotesReferences==
 
<references>
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| volume = 35
| date = 2002
| issue = 4
| pages = 433–448
| doi = 10.1007/s00224-002-1010-5
| url = https://www.lix.polytechnique.fr/~bournez/load/Papier-TOCS-2002.pdf
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</references>
 
* {{Cite journal |last1=Bell |first1=Paul |last2=Potapov |first2=Igor |date=2008-02-04 |title=On undecidability bounds for matrix decision problems |url=https://www.sciencedirect.com/science/article/pii/S0304397507007840 |journal=Theoretical Computer Science |series=Combinatorics, Automata and Number Theory |volume=391 |issue=1 |pages=3–13 |doi=10.1016/j.tcs.2007.10.025 |issn=0304-3975}}
 
* {{Cite report |url=https://dl.acm.org/doi/10.5555/893250 |title=Decidable and Undecidable Problems in Matrix Theory |last=Halava |first=Vesa |date=August 1997 |publisher=Turku Centre for Computer Science }}>
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[[Category:Undecidable problems]]
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[[Category:Unsolved problems in mathematics]]
[[Category:Matrix theory]]
 
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