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.
منابع مشابه
Constructing Complete Projectively Flat Connections
Theorem 1. Let T 2 be the two dimensional torus. Then for any positive integer m there is a complete torsion free projectively flat connection, ∇, on T 2 such that for any point p ∈ T 2 there is a point q ∈ T 2 with the property that any broken ∇-geodesic between p and q has at least m breaks. Moreover if T 2 is viewed as a Lie group in the usual manner, this connection is invariant under trans...
متن کاملOn a class of locally projectively flat Finsler metrics
In this paper we study Finsler metrics with orthogonal invariance. We find a partial differential equation equivalent to these metrics being locally projectively flat. Some applications are given. In particular, we give an explicit construction of a new locally projectively flat Finsler metric of vanishing flag curvature which differs from the Finsler metric given by Berwald in 1929.
متن کاملProjectively Flat Finsler Metrics of Constant Curvature
It is the Hilbert’s Fourth Problem to characterize the (not-necessarilyreversible) distance functions on a bounded convex domain in R such that straight lines are shortest paths. Distance functions induced by a Finsler metric are regarded as smooth ones. Finsler metrics with straight geodesics said to be projective. It is known that the flag curvature of any projective Finsler metric is a scala...
متن کاملA Theory of Multi-Layer Flat Refractive Geometry∗ Supplementary Materials
In this section, we describe in detail the analytical solutions to compute the layer thicknesses and translation along the axis when refractive indices are unknown. As shown in the paper, the axis can be computed independently of the layer thicknesses and refractive indices. We assume that axis A, rotation R and translation orthogonal to the axis, tA, has been computed as described in Section 3...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Physica Scripta
سال: 2021
ISSN: ['1402-4896', '0031-8949']
DOI: https://doi.org/10.1088/1402-4896/ac3a51