# On an *f*(*R*) theory of gravity based on non-conformal invariance of gravitational waves

*S.N. Pandey*^{1}

(1) Ex-Professor and Head, Department of Applied Sciences, M.M.M. Engineering College, Gorakhpur, India

### Abstract

Gravitational waves are an inevitable consequence of Einstein's theory of gravitation, which are meaningfully comparable with electromagnetic waves except for their non-conformal invariance. So, Einstein's field equations aremodified by a straightforward generalization of the Lagrangian in the Einstein-Hilbert action by choosing a polynomial in the scalar *R* of a finite number of terms. In this modified theory of gravity, conformally invariant gravitational waves are obtained. Besides this, cosmological aspects and the gravitational field surrounding a spherically symmetric mass distribution are studied to understand the features of this theory. It reveals that the deviations are not so significant at the observational level, and the features are more or less similar to those of Einstein's theory.

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