Geometric symmetries on Lorentzian manifolds
نویسنده
چکیده
Lie derivatives of various geometrical and physical quantities define symmetries and conformal symmetries in general relativity. Thus we obtain motions, collineations, conformal motions and conformal collineations. These symmetries are used not only to find new solutions of Einstein’s field equations but to classify the spaces also. Different classification schemes are presented here. Relationships between these symmetries are discussed and illustrating examples are presented. ∗On leave from: Centre for Advanced Mathematics and Physics, National University of Sciences and Technology, Rawalpindi, Pakistan, and Department of Mathematics, Quaid-i-Azam University, Islamabad, Pakistan.
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