

New Solutions Found for the Boltzmann Equation - mahipal
http://www.upenn.edu/pennnews/news/university-pennsylvania-mathematicians-solve-140-year-old-boltzmann-equation-gaseous-behaviors

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gjm11
Paper is at <http://arxiv.org/abs/0912.0888> . The Boltzmann equation
describes the motion of particles in a fluid. If I've understood the opening
section of the paper correctly (which I may not have done), other people have
found solutions of the Boltzmann equation under some rather unrealistic
assumptions about the distribution of relative velocities when particles
collide. (AIUI you're supposed to work out that distribution by doing some
actual physics, then plug it into the equation; the solutions describe the
behaviour of a fluid with the properties encoded in that distribution.)
Specifically, past work has required the assumption that collisions at shallow
glancing angles never happen, which is typically far from the truth. What's
new in this paper is that they've got rid of those unrealistic assumptions. I
think.

