Jeans criterion and nonextensive velocity distribution function in kinetic theory

Jiulin Du

doi:10.1016/j.physleta.2003.11.047

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Jeans criterion and nonextensive velocity distribution function in kinetic theory

Jiulin Du

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Abstract

The effect of nonextensivity of self-gravitating systems on the Jeans criterion for gravitational instability is studied in the framework of Tsallis statistics. The nonextensivity is introduced in the Jeans problem by a generalized q-nonextensive velocity distribution function through the equation of state of ideal gas in nonextensive kinetic theory. A new Jeans criterion is deduced with a factor that, however, differs from that one in Ref.[21] and new results of gravitational instability are analyzed for the nonextensive parameter q. An understanding of physical meaning of q and a possible seismic observation to find astronomical evidence for a value of q different from unity are also discussed.

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Jiulin Du. 2004-04-23. Jeans criterion and nonextensive velocity distribution function in kinetic theory. https://doi.org/10.1016/j.physleta.2003.11.047

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