Heat pinch: Difference between revisions

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I.e., the gradient of the heat conductivity produces a 'natural' pinch.
I.e., the gradient of the heat conductivity produces a 'natural' pinch.
It should be noted that at the ''descriptive'' level, the Fick and Fokker-Planck equations are fully equivalent and capable of describing the same phenomena (with one exception<ref>[[doi:10.1088/0143-0807/26/5/023|B.Ph. van Milligen, P.D. Bons, B.A. Carreras and R. Sánchez, ''On the applicability of Fick’s law to diffusion in inhomogeneous systems'', Eur. J. Phys. '''26''' (2005) 913–925]]</ref>).
It is only at the ''interpretative'' level that this difference appears: a 'pinch' may seem mysterious when using Fick's equation, while it appears 'natural' when using the Fokker-Planck equation.


== Mesoscopic and microscopic mechanisms ==
== Mesoscopic and microscopic mechanisms ==