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On the geometric approach to the motion of inertial mechanical systems

Constantin, Adrian LU and Kolev, B (2002) In Journal of Physics A: Mathematical and General 35(32). p.51-79
Abstract
According to the principle of least action, the spatially periodic motions of one-dimensional mechanical systems with no external forces are described in the Lagrangian formalism by geodesics on a manifold-configuration space, the group D of smooth orientation-preserving diffeomorphisms of the circle. The periodic inviscid Burgers equation is the geodesic equation on D with the L-2 right-invariant metric. However, the exponential map for this right-invariant metric is not a C-1 local diffeomorphism and the geometric structure is therefore deficient. On the other hand, the geodesic equation on D for the H-1 right-invariant metric is also a re-expression of a model in mathematical physics. We show that in this case the exponential map is a... (More)
According to the principle of least action, the spatially periodic motions of one-dimensional mechanical systems with no external forces are described in the Lagrangian formalism by geodesics on a manifold-configuration space, the group D of smooth orientation-preserving diffeomorphisms of the circle. The periodic inviscid Burgers equation is the geodesic equation on D with the L-2 right-invariant metric. However, the exponential map for this right-invariant metric is not a C-1 local diffeomorphism and the geometric structure is therefore deficient. On the other hand, the geodesic equation on D for the H-1 right-invariant metric is also a re-expression of a model in mathematical physics. We show that in this case the exponential map is a C-1 local diffeomorphism and that if two diffeomorphisms are sufficiently close on D, they can be joined by a unique length-minimizing geodesic-a state of the system is transformed to another nearby state by going through a uniquely determined flow that minimizes the energy. We also analyse for both metrics the breakdown of the geodesic flow. (Less)
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author
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organization
publishing date
type
Contribution to journal
publication status
published
subject
in
Journal of Physics A: Mathematical and General
volume
35
issue
32
pages
51 - 79
publisher
IOP Publishing
external identifiers
  • wos:000178047800003
  • scopus:0042279206
ISSN
0305-4470
DOI
10.1088/0305-4470/35/32/201
language
English
LU publication?
yes
id
b4102394-54f6-4bc5-ba09-d7fbb1521cd5 (old id 328289)
date added to LUP
2016-04-01 16:08:57
date last changed
2022-04-15 02:27:24
@article{b4102394-54f6-4bc5-ba09-d7fbb1521cd5,
  abstract     = {{According to the principle of least action, the spatially periodic motions of one-dimensional mechanical systems with no external forces are described in the Lagrangian formalism by geodesics on a manifold-configuration space, the group D of smooth orientation-preserving diffeomorphisms of the circle. The periodic inviscid Burgers equation is the geodesic equation on D with the L-2 right-invariant metric. However, the exponential map for this right-invariant metric is not a C-1 local diffeomorphism and the geometric structure is therefore deficient. On the other hand, the geodesic equation on D for the H-1 right-invariant metric is also a re-expression of a model in mathematical physics. We show that in this case the exponential map is a C-1 local diffeomorphism and that if two diffeomorphisms are sufficiently close on D, they can be joined by a unique length-minimizing geodesic-a state of the system is transformed to another nearby state by going through a uniquely determined flow that minimizes the energy. We also analyse for both metrics the breakdown of the geodesic flow.}},
  author       = {{Constantin, Adrian and Kolev, B}},
  issn         = {{0305-4470}},
  language     = {{eng}},
  number       = {{32}},
  pages        = {{51--79}},
  publisher    = {{IOP Publishing}},
  series       = {{Journal of Physics A: Mathematical and General}},
  title        = {{On the geometric approach to the motion of inertial mechanical systems}},
  url          = {{http://dx.doi.org/10.1088/0305-4470/35/32/201}},
  doi          = {{10.1088/0305-4470/35/32/201}},
  volume       = {{35}},
  year         = {{2002}},
}