Harmonicity of vector fields on a class of Lorentzian solvable Lie groups
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Ju Tan
Abstract
In this paper, we consider a special class of solvable Lie groups such that for any x, y in their Lie algebras, [x, y] is a linear combination of x and y. We investigate the harmonicity properties of invariant vector fields of this kind of Lorentzian Lie groups. It is shown that any invariant unit time-like vector field is spatially harmonic. Moreover, we determine all vector fields which are critical points of the energy functional restricted to the space of smooth vector fields.
Acknowledgements
The authors are deeply grateful to the referees for valuable comments and helpful suggestions.
Funding: This work was supported by NSFC (no. 11271198, 51535008, 11671212) and SRFDP of China.
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© 2018 Walter de Gruyter GmbH, Berlin/Boston
Artikel in diesem Heft
- Frontmatter
- Graphs and metric 2-step nilpotent Lie algebras
- Stein manifolds of nonnegative curvature
- Homogeneous spin Riemannian manifolds with the simplest Dirac operator
- On the quantum periods of del Pezzo surfaces with ⅓ (1, 1) singularities
- Harmonicity of vector fields on a class of Lorentzian solvable Lie groups
- Uniform cover inequalities for the volume of coordinate sections and projections of convex bodies
- Criteria for Hattori–Masuda multi-polytopes via Duistermaat–Heckman functions and winding numbers
- On complex Berwald metrics which are not conformal changes of complex Minkowski metrics
- Continuous space-time transformations
Artikel in diesem Heft
- Frontmatter
- Graphs and metric 2-step nilpotent Lie algebras
- Stein manifolds of nonnegative curvature
- Homogeneous spin Riemannian manifolds with the simplest Dirac operator
- On the quantum periods of del Pezzo surfaces with ⅓ (1, 1) singularities
- Harmonicity of vector fields on a class of Lorentzian solvable Lie groups
- Uniform cover inequalities for the volume of coordinate sections and projections of convex bodies
- Criteria for Hattori–Masuda multi-polytopes via Duistermaat–Heckman functions and winding numbers
- On complex Berwald metrics which are not conformal changes of complex Minkowski metrics
- Continuous space-time transformations
