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Jeans' gravitational instability and nonextensive kinetic theory

J. A. S. Lima·R. Silva·J. Santos
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Abstract

The concept of Jeans gravitational instability is rediscussed in the framework of nonextensive statistics and its associated kinetic theory. A simple analytical formula generalizing the Jeans criterion is derived by assuming that the unperturbed self- gravitating collisionless gas is kinetically described by the $q$-parameterized class of power law velocity distributions. It is found that the critical values of wavelength and mass depend explicitly on the nonextensive $q$-parameter. The standard Jeans wavelength derived for a Maxwellian distribution is recovered in the limiting case $q$=1. For power-law distributions with cutoff, the instability condition is weakened with the system becoming unstable even for wavelengths of the disturbance smaller than the standard Jeans length $λ_J$.

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J. A. S. Lima, R. Silva, J. Santos. 2002-11-19. Jeans' gravitational instability and nonextensive kinetic theory. https://doi.org/10.1051/0004-6361%3A20021395

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