Density fluctuations and energy spectra of 3D bacterial suspensions.

  title={Density fluctuations and energy spectra of 3D bacterial suspensions.},
  author={Zhengyang Liu and Wei-Gang Zeng and Xiaolei Ma and Xiang Cheng},
  journal={Soft matter},
Giant number fluctuations are often considered as a hallmark of the emergent nonequilibrium dynamics of active fluids. However, these anomalous density fluctuations have only been reported experimentally in two-dimensional dry active systems heretofore. Here, we investigate density fluctuations of bulk Escherichia coli suspensions, a paradigm of three-dimensional (3D) wet active fluids. Our experiments demonstrate the existence and quantify the scaling relation of giant number fluctuations inโ€ฆย 

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