Metric mean dimension of flows

The present paper aims to investigate the metric mean dimension theory of continuous flows. We introduce the notion of metric mean dimension for continuous flows to characterize the complexity of flows with infinite topological entropy. For continuous flows, we establish variational principles for metric mean dimension in terms of local $\epsilon$-entropy function and Brin-Katok $\epsilon$-entropy; For a class of special flow, called uniformly Lipschitz flow, we establish variational principles for metric mean dimension in terms of Kolmogorov-Sinai $\epsilon$-entropy, Brin-Katok's $\epsilon$-entropy and Katok's $\epsilon$-entropy.