## Revista Matemática Iberoamericana

### Explicit spectral gap estimates for the linearized Boltzmann and Landau operators with hard potentials

#### Abstract

This paper deals with explicit spectral gap estimates for the linearized Boltzmann operator with hard potentials (and hard spheres). We prove that it can be reduced to the Maxwellian case, for which explicit estimates are already known. Such a method is constructive, does not rely on Weyl's Theorem and thus does not require Grad's splitting. The more physical idea of the proof is to use geometrical properties of the whole collision operator. In a second part, we use the fact that the Landau operator can be expressed as the limit of the Boltzmann operator as collisions become grazing in order to deduce explicit spectral gap estimates for the linearized Landau operator with hard potentials.

#### Article information

Source
Rev. Mat. Iberoamericana, Volume 21, Number 3 (2005), 819-841.

Dates
First available in Project Euclid: 11 January 2006

https://projecteuclid.org/euclid.rmi/1136999132

Mathematical Reviews number (MathSciNet)
MR2231011

Zentralblatt MATH identifier
1092.76057

#### Citation

Baranger, Céline; Mouhot, Clément. Explicit spectral gap estimates for the linearized Boltzmann and Landau operators with hard potentials. Rev. Mat. Iberoamericana 21 (2005), no. 3, 819--841. https://projecteuclid.org/euclid.rmi/1136999132

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