Geodesics and geodesic deviation for impulsive gravitational waves
Steinbauer, Roland
arXiv, 9710119 / Harvested from arXiv
The geometry of impulsive pp-waves is explored via the analysis of the geodesic and geodesic deviation equation using the distributional form of the metric. The geodesic equation involves formally ill-defined products of distributions due to the nonlinearity of the equations and the presence of the Dirac $\de$-distribution in the space time metric. Thus, strictly speaking, it cannot be treated within Schwartz's linear theory of distributions. To cope with this difficulty we proceed by first regularizing the $\de$-singularity,then solving the regularized equation within classical smooth functions and, finally, obtaining a distributional limit as solution to the original problem. Furthermore it is shown that this limit is independent of the regularization without requiring any additional condition, thereby confirming earlier results in a mathematical rigorous fashion. We also treat the Jacobi equation which, despite being linear in the deviation vector field, involves even more delicate singular expressions, like the ``square'' of the Dirac $\de$-distribution. Again the same regularization procedure provides us with a perfectly well behaved smooth regularization and a regularization-independent distributional limit. Hence it is concluded that the geometry of impulsive pp-waves can be described consistently using distributions as long as careful regularization procedures are used to handle the ill-defined products.
Publié le : 1997-10-28
Classification:  General Relativity and Quantum Cosmology,  Mathematical Physics
@article{9710119,
     author = {Steinbauer, Roland},
     title = {Geodesics and geodesic deviation for impulsive gravitational waves},
     journal = {arXiv},
     volume = {1997},
     number = {0},
     year = {1997},
     language = {en},
     url = {http://dml.mathdoc.fr/item/9710119}
}
Steinbauer, Roland. Geodesics and geodesic deviation for impulsive gravitational waves. arXiv, Tome 1997 (1997) no. 0, . http://gdmltest.u-ga.fr/item/9710119/