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Predicting the dark matter particle mass, size, and other properties from the mass and energy cascade and two-thirds law in dark matter flow

ORAL

Abstract

How can the fluid mechanics help us understand the dark matter mystery - the biggest quest of contemporary astrophysics? After years of null results in the search for thermal WIMPs, a different prospective might be required. We present a new fluid mechanics approach to estimate the dark matter particle mass, size and many other relevant properties based on the nature of flow of dark matter. A comparison with hydrodynamic turbulence is presented to reveal the unique features of dark matter flow, i.e. an inverse mass and energy cascade from small to large scales with a scale-independent rate of energy cascade εu=-4.6x10-7m2/s3. If gravity is the only interaction involved and viscosity is absent, the energy cascade leads to a two-thirds law for pairwise velocity that can be extended down to the smallest scale, where quantum effects become important. Combining the rate of energy cascade εu, Planck constant h, and gravitational constant G on that scale, mass of dark matter particles is found to be around 1012GeV with a size around 10-13m. This strongly suggests a heavy dark matter scenario with a mass much greater than standard WIMPs. The accompanying slides and datasets for this work can be found on Zenodo.org by searching "dark matter flow" or https://doi.org/10.5281/zenodo.6569901.

Publication: Dark matter particle mass, size, and properties from energy cascade and two-thirds law in dark matter flow (https://doi.org/10.48550/arxiv.2202.07240)

Presenters

  • Zhijie Xu

    Pacific Northwest National Laboratory

Authors

  • Zhijie Xu

    Pacific Northwest National Laboratory