Skip to content
DraconiticResearch
Search Sources API
201,818 studies31 sourcesUpdated 13 min ago
PreprintarXiv licencearXiv

Sophus Lie's problem on two-dimensional metrics with projective symmetries: completing the local classification

Abstract

We complete the local classification, up to isometry, of $2$-dimensional pseudo-Riemannian metrics (i.e. both Riemannian and Lorentzian), admitting a projective symmetry algebra of dimension at least two. The new contribution is the treatment of the non-regular case: we obtain a complete list of mutually non-isometric normal forms in neighbourhoods of points where the action of the projective Lie symmetry algebra fails to be regular, including all singular behaviours that can occur. Together with the known classification in the regular case, this completes the solution of the problem posed by Sophus Lie in 1882.

Related

  1. Arithmetic classification of the Dirichlet eigenvalues for a one-dimensional nonlocal p-Laplacian problem
    Shingo Takeuchi
    arXivPreprintarXiv licenceFull textAlgebra & number theoryAnalysis & PDEsarXiv
  2. Completing the classification of Hopf superalgebras of dimension up to 10
    Taiki Shibata, Kenichi Shimizu, Ryota Wakao
    arXivPreprintarXiv licenceFull textAlgebra & number theoryarXiv
  3. Completing the Existence Problem for Integer Relative Heffter Arrays Hk(n;k)
    Lorenzo Mella
    arXivPreprintCC BY 4.0Full textCombinatorics & discrete mathematicsarXiv
  4. Projective symmetries of Chebyshev polynomials
    Saeed Tafazolian, Jaap Top
    arXivPreprintCC BY 4.0Full textAlgebra & number theoryarXiv
  5. Moduli Spaces of Homologically Trivial Parabolic (Higgs) Bundles on the Projective Line and an Application to the Deligne-Simpson Problem
    Xueqing Wen
    Symmetry, Integrability and Geometry: Methods and ApplicationsPeer-reviewedCC BY-SA 4.0Full textGeometry & topologyCrossref
BibTeX
@misc{manno2026sophus,
  title = {{Sophus Lie's problem on two-dimensional metrics with projective symmetries: completing the local classification}},
  author = {Gianni Manno and Vladimir S. Matveev and Filippo Salis},
  howpublished = {arXiv},
  year = {2026},
  month = sep,
  doi = {10.48550/arxiv.2609.05280},
  eprint = {2609.05280},
  archivePrefix = {arXiv},
  url = {https://arxiv.org/abs/2609.05280},
}
RIS
TY  - UNPB
TI  - Sophus Lie's problem on two-dimensional metrics with projective symmetries: completing the local classification
AU  - Gianni Manno
AU  - Vladimir S. Matveev
AU  - Filippo Salis
PY  - 2026
DA  - 2026/09/04
PB  - arXiv
DO  - 10.48550/arxiv.2609.05280
UR  - https://arxiv.org/abs/2609.05280
AB  - We complete the local classification, up to isometry, of $2$-dimensional pseudo-Riemannian metrics (i.e. both Riemannian and Lorentzian), admitting a projective symmetry algebra of dimension at least two. The new contribution is the treatment of the non-regular case: we obtain a complete list of mutually non-isometric normal forms in neighbourhoods of points where the action of the projective Lie symmetry algebra fails to be regular, including all singular behaviours that can occur. Together with the known classification in the regular case, this completes the solution of the problem posed by Sophus Lie in 1882.
ER  -