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Structure and dynamical behavior of non-normal networks.

ABSTRACT: We analyze a collection of empirical networks in a wide spectrum of disciplines and show that strong non-normality is ubiquitous in network science. Dynamical processes evolving on non-normal networks exhibit a peculiar behavior, as initial small disturbances may undergo a transient phase and be strongly amplified in linearly stable systems. In addition, eigenvalues may become extremely sensible to noise and have a diminished physical meaning. We identify structural properties of networks that are associated with non-normality and propose simple models to generate networks with a tunable level of non-normality. We also show the potential use of a variety of metrics capturing different aspects of non-normality and propose their potential use in the context of the stability of complex ecosystems.

SUBMITTER: Asllani M

PROVIDER: S-EPMC6291309 | biostudies-other | 2018 Dec

REPOSITORIES: biostudies-other

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Structure and dynamical behavior of non-normal networks.

Asllani Malbor M Lambiotte Renaud R Carletti Timoteo T

Science advances 20181212 12

We analyze a collection of empirical networks in a wide spectrum of disciplines and show that strong non-normality is ubiquitous in network science. Dynamical processes evolving on non-normal networks exhibit a peculiar behavior, as initial small disturbances may undergo a transient phase and be strongly amplified in linearly stable systems. In addition, eigenvalues may become extremely sensible to noise and have a diminished physical meaning. We identify structural properties of networks that a ...[more]

PMID: 30547090

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