Fractality and kinetics of the stellar medium in the solar neighborhood based on Gaia DR2 data

The fractal nature of the stellar medium in the Solar vicinity has been established by studying 200 000 stars of all spectral types at distances of 1 to 100 parsec from the Sun. The fractal dimension is $D \approx 2.41$. Based on the data obtained, we examine the kinetic properties of the fractal stellar medium in the solar vicinity. We show that kinetic parameters such as correlation length, dynamic friction coefficient, effective interstellar distance for fractal stellar medium differ from the1 corresponding parameters for quasi-homogeneous medium with limited density fluctuations, and depend on the fractal dimension. We find that the fractal structure of the stellar medium leads to a reduction of the relaxation time in our Galaxy.