Author

# Tatsuyoshi Hamada

Other affiliations: Nihon University

Bio: Tatsuyoshi Hamada is an academic researcher from Fukuoka University. The author has contributed to research in topic(s): Ricci curvature & Mathematical software. The author has an hindex of 5, co-authored 17 publication(s) receiving 124 citation(s). Previous affiliations of Tatsuyoshi Hamada include Nihon University.

##### Papers

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TL;DR: In this article, the authors classified the $*$-Einstein real hypersurfaces in complex space forms such that the structure vector is a principal curvature vector and the principal curvatures of the hypersurface can be computed with the K\"ahler metric.

Abstract: It is known that there are no Einstein real hypersurfaces in complex space forms equipped
with the K\"ahler metric. In the present paper we classified the $*$-Einstein real
hypersurfaces $M$ in complex space forms $M_{n}(c)$ and such that the structure vector is
a principal curvature vector.

54 citations

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TL;DR: In this article, it was shown that there are no real hypersurfaces with recurrent Ricci tensors of the complex projective space Pn(C) under the condition that there is a principal curvature vector.

Abstract: Let M be a real hypersurface of the complex projective space
Pn(C). The Ricci tensor S
of M is recurrent if there exists a 1-form such that . In this paper we show that there
are no real hypersurfaces with recurrent Ricci tensor of
Pn(C) under the condition that is a principal curvature vector.1991 Mathematics
Subject Classification 53C40
(53C25).

16 citations

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15 citations

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TL;DR: This tutorial demonstrates how to boot and use the KNOPPIX/Math system, a wonderful world of mathematical software without needing to install anything yourself.

Abstract: KNOPPIX/Math offers many documents and mathematical software packages. Once you run the live system, you can enjoy a wonderful world of mathematical software without needing to install anything yourself. We will demonstrate how to boot and use this system.

7 citations

##### Cited by

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TL;DR: In this paper, the notion of *-Ricci soliton is introduced and real hypersurfaces in non-flat complex space forms admitting a *-ricci s soliton with potential vector field being the structure vector field.

Abstract: In this paper the notion of *-Ricci soliton is introduced and real hypersurfaces in non-flat complex space forms admitting a *-Ricci soliton with potential vector field being the structure vector field ξ are studied. At the end of the paper discussion on this new notion and ideas for further work are presented.

31 citations

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TL;DR: In this paper, the authors classify real hypersurfaces of complex projective space C P m, m ⩾ 3, with D -recurrent structure Jacobi operator and apply this result to prove the non-existence of such hypersurface with recurrent structure JacobI operator.

Abstract: We classify real hypersurfaces of complex projective space C P m , m ⩾ 3 , with D -recurrent structure Jacobi operator and apply this result to prove the non-existence of such hypersurfaces with recurrent structure Jacobi operator.

31 citations

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TL;DR: In this paper, the geometry of homogeneous hypersurfaces and their focal sets in complex hyperbolic spaces is studied and a characterization of the focal set in terms of its second fundamental form is provided.

Abstract: We study the geometry of homogeneous hypersurfaces and their focal sets in complex hyperbolic spaces. In particular, we provide a characterization of the focal set in terms of its second fundamental form and determine the principal curvatures of the homogeneous hypersurfaces together with their multiplicities.

28 citations

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TL;DR: In this paper, a reduction result for parallel symmetric covariant tensor fields of order two was obtained for the parallel Ricci solitons with regularity and regularity conditions.

Abstract: Torse-forming $\eta $-Ricci solitons are studied in the framework of almost paracontact metric $\eta $-Einstein manifolds. By adding a technical condition, called regularity and concerning with the scalars provided by the two $\eta $-conditions, is obtained a reduction result for the parallel symmetric covariant tensor fields of order two.

27 citations

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TL;DR: The article gives a survey of mathematical proofs that rely on computer calculations and formal proofs, as well as some examples from the literature.

Abstract: The article gives a survey of mathematical proofs that rely on computer calculations and formal proofs.

20 citations