How a projectively flat geometry regulates F(R)-gravity theory?

نویسندگان

چکیده

Abstract In the present paper we examine a projectively flat spacetime solution of F ( R )-gravity theory. It is seen that once deploy projective flatness in geometry spacetime, matter field has constant energy density and isotropic pressure. We then make condition weaker discuss effects harmonic theory show this case reduces to generalised Robertson-Walker with shear, vorticity, acceleration free perfect fluid specific form expansion scalar presented terms scale factor. Role conharmonic curvature tensor also briefly discussed. Some analysis obtained results are conducted couple models.

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ژورنال

عنوان ژورنال: Physica Scripta

سال: 2021

ISSN: ['1402-4896', '0031-8949']

DOI: https://doi.org/10.1088/1402-4896/ac3a51