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The complexity of divisibility. | LitMetric

The complexity of divisibility.

Linear Algebra Appl

DAMTP, Centre for Mathematical Sciences, University of Cambridge, Wilberforce Road, Cambridge CB3 0WB, UK.

Published: September 2016

AI Article Synopsis

Article Abstract

We address two sets of long-standing open questions in linear algebra and probability theory, from a computational complexity perspective: stochastic matrix divisibility, and divisibility and decomposability of probability distributions. We prove that finite divisibility of stochastic matrices is an NP-complete problem, and extend this result to nonnegative matrices, and completely-positive trace-preserving maps, i.e. the quantum analogue of stochastic matrices. We further prove a complexity hierarchy for the divisibility and decomposability of probability distributions, showing that finite distribution divisibility is in P, but decomposability is NP-hard. For the former, we give an explicit polynomial-time algorithm. All results on distributions extend to weak-membership formulations, proving that the complexity of these problems is robust to perturbations.

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Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5465997PMC
http://dx.doi.org/10.1016/j.laa.2016.03.041DOI Listing

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