Princeton Center for Heliophysics Seminar

Most space and astrophysical plasmas are considered to be in turbulent state, often characterized by stochastic fluctuations. Many laboratory experiments and numerical simulations have revealed chaotic behavior in turbulent plasmas, but in-situ observations of turbulent plasmas in natural environments have only shown highly stochastic signatures. Here, we present in-situ evidence of chaotic signal in the turbulent solar wind plasma downstream of the Earth’s bow shock. By analyzing the relative location of magnetic-field fluctuations on the permutation entropy-complexity plane (C-H plane), we show that turbulence in the magnetosheath plasma exhibits characteristics of chaotic fluctuations rather than stochastic behavior. This finding challenges established notions of plasma turbulence and reveals the need for caution when using the magnetosheath as a laboratory for studying plasma turbulence.