## Annals of Applied Probability

### Upper bounds for the function solution of the homogeneous $2D$ Boltzmann equation with hard potential

#### Abstract

We deal with $f_{t}(dv)$, the solution of the homogeneous $2D$ Boltzmann equation without cutoff. The initial condition $f_{0}(dv)$ may be any probability distribution (except a Dirac mass). However, for sufficiently hard potentials, the semigroup has a regularization property (see Probab. Theory Related Fields 151 (2011) 659–704): $f_{t}(dv)=f_{t}(v)\,dv$ for every $t>0$. The aim of this paper is to give upper bounds for $f_{t}(v)$, the most significant one being of type $f_{t}(v)\leq Ct^{-\eta}e^{-\vert v\vert^{\lambda}}$ for some $\eta,\lambda>0$.

#### Article information

Source
Ann. Appl. Probab., Volume 29, Number 3 (2019), 1929-1961.

Dates
Revised: August 2018
First available in Project Euclid: 19 February 2019

https://projecteuclid.org/euclid.aoap/1550566847

Digital Object Identifier
doi:10.1214/18-AAP1451

Mathematical Reviews number (MathSciNet)
MR3914561

Zentralblatt MATH identifier
07057471

#### Citation

Bally, Vlad. Upper bounds for the function solution of the homogeneous $2D$ Boltzmann equation with hard potential. Ann. Appl. Probab. 29 (2019), no. 3, 1929--1961. doi:10.1214/18-AAP1451. https://projecteuclid.org/euclid.aoap/1550566847

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