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arXiv · 1506.08764

A discerning gravitational property for gravitational equation in higher dimensions

Naresh Dadhich
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Abstract

It is well-known that Einstein gravity is kinematic (no non-trivial vacuum solution;i.e. Riemann vanishes whenever Ricci does so) in $3$ dimension because Riemann is entirely given in terms of Ricci. Could this property be universalized for all odd dimensions in a generalized theory? The answer is yes, and this property uniquely singles out pure Lovelock (it has only one $N$th order term in action) gravity for which $N$th order Lovelock Riemann tensor is indeed given in terms of corresponding Ricci for all odd $d=2N+1$ dimensions. This feature of gravity is realized only in higher dimensions and it uniquely picks out pure Lovelock gravity from all other generalizations of Einstein gravity. It serves as a good discerning and guiding criterion for gravitational equation in higher dimensions.

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Naresh Dadhich. 2015-06-16. A discerning gravitational property for gravitational equation in higher dimensions. https://doi.org/10.1140/epjc%2Fs10052-016-3933-z

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