Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Lagrangian dynamics in inhomogeneous and thermal environments, An
  application of the Onsager-Machlup theory I   We straight-forwardly derive the Onsager-Machlup Lagrangian from the
Fokker-Planck equation and show that friction and dissipation are a natural
property of the equation of motion. We develop a method to calculate the local
variance $\sigma_{2}\,b(q)^{2}$ and identify this function as a
Helmholtz-factor. In both meanings the function $b(q)$ describes properties of
the environment. For application, we examine the free fall through a barometric
medium and model a blow of wind by a solitonic pulse running through the
medium. We treat harmonic oscillators immersed in a thermal bath, finding
intuitive as well as counter-intuitive phenomena of friction. By allowing the
temperature to be time-dependent, the dynamical process of cooling and heating
becomes self-consistently available. We find a state of dynamical balance
between system and environment. Last, we show that dynamical balance is related
to adiabatic thermodynamic processes. In a special case, dynamical balance can
induce a real phase-transition.

17
The categories of this paper are: q-fin
14
The categories of this paper are: math-ph
27
The categories of this paper are: comp-gas
7
The categories of this paper are: hep-th
32
The categories of this paper are: atom-ph
30
The categories of this paper are: q-alg
15
The categories of this paper are: nucl-ex
33
The categories of this paper are: plasm-ph
0
The categories of this paper are: hep-ph
20
The categories of this paper are: acc-phys
21
The categories of this paper are: adap-org
8
The categories of this paper are: hep-ex
19
The categories of this paper are: eess
13
The categories of this paper are: quant-ph
31
The categories of this paper are: ao-sci
23
The categories of this paper are: solv-int