Velocity Correlations in an Active Nematic

TL;DR

This paper investigates the flow properties of an active nematic model, revealing that velocity correlation length remains constant with activity changes while the velocity scale increases, aligning with experimental findings.

Contribution

It provides a continuum model analysis linking defect dynamics to flow properties, matching experimental observations of active nematic suspensions.

Findings

Velocity correlation length is activity-independent.

Characteristic velocity scale increases with activity.

Results align with recent experimental data.

Abstract

The flow properties of a continuum model for an active nematic is studied and compared with recent experiments on suspensions of microtubule bundles and molecular motors. The velocity correlation length is found to be independent of the strength of the activity while the characteristic velocity scale increases monotonically as the activity is increased, both in agreement with the experimental observations. We interpret our results in terms of the creation and annihilation dynamics of a gas of topological defects.