Introduction
In this paper, by using the concept of spherically symmetric Finsler metric, we define the notion of
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-projectively related metrics as an extension of projectively related metrics. We construct some non-trivial examples of
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-projectively related metrics. Let
F and
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be two
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-projectively related metrics on a manifold
M. We find the relation between the geodesics of
F and
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and prove that any geodesic of
F is a multiple of a geodesic of
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and the other way around. There are several projective invariants of Finsler metrics, namely, Douglas metrics, Weyl metrics and generalized Douglas-Weyl curvature. We prove that the Douglas metrics, Weyl metrics and generalized Douglas-Weyl metrics are
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-projective invariants.
Material and methods
First we obtain the spray coefficients of a spherically symmetric Finsler metric. By considering it, we define
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-projectively related metrics which is a generalization of projectively related Finsler metrics. Then we find the geodesics of two
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-projectively related metrics. We obtain the relation between Douglas, Weyl and generalized Douglas-Weyl curvatures of two
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-projectively related metrics.
Results and discussion
We find the Douglas curvature, Weyl curvature and generalized Douglas-Weyl curvature of two
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-projectively related Finsler metrics. These calculations tell us that these class of Finsler metrics are
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-projective invariants.
Conclusion
The following conclusions were drawn from this research.
- We prove that the Douglas curvature, Weyl curvature and generalized Douglas-Weyl curvature are
-projective invariants.
- Let F and
be two
-projectively related metrics on a manifold M. We show that F is a Berwald metric if and only if
is a Berwald metric. ./files/site1/files/64/12.pdf
Type of Study:
Original Manuscript |
Subject:
alg Received: 2018/10/31 | Revised: 2021/02/16 | Accepted: 2019/07/23 | Published: 2021/01/29 | ePublished: 2021/01/29