Black hole perturbation in the most general scalar-tensor theory with second-order field equations. II. The even-parity sector

In this work we study a general scalar-tensor theory in which the coupling and potential functions are determined from Noether symmetry arguments. We also obtain exact solutions of the field equations and found that the universe asymptotically follows an exponential expansion having no graceful exit. The study of the functional form of ω(φ) reveals that the theory asymptotically becomes an attractor of general relativity. We restrict ourselves to spatially homogeneous, isotropic flat universe.

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Energy Conditions in a Generalized Second-Order Scalar-Tensor Gravity

Advances in High Energy Physics ◽

10.1155/2013/253985 ◽

2013 ◽

Vol 2013 ◽

pp. 1-15 ◽

Cited By ~ 3

Author(s):

M. Sharif ◽

Saira Waheed

Keyword(s):

Second Order ◽

Energy Conditions ◽

Field Equations ◽

Frw Universe ◽

Tensor Theory ◽

Modified Gravity Theories ◽

General Scalar ◽

General Relativistic ◽

Fluid Matter ◽

Free Parameters

The study of energy conditions has many significant applications in general relativistic and cosmological contexts. This paper explores the energy conditions in the framework of the most general scalar-tensor theory with field equations involving second-order derivatives. For this purpose, we use flat FRW universe model with perfect fluid matter contents. By taking power law ansatz for scalar field, we discuss the strong, weak, null, and dominant energy conditions in terms of deceleration, jerk, and snap parameters. Some particular cases of this theory likek-essence model, modified gravity theories and so forth. are analyzed with the help of the derived energy conditions, and the possible constraints on the free parameters of the presented models are determined.

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The most general second-order field equations of bi-scalar-tensor theory in four dimensions

Journal of High Energy Physics ◽

10.1007/jhep07(2015)008 ◽

2015 ◽

Vol 2015 (7) ◽

Cited By ~ 28

Author(s):

Seiju Ohashi ◽

Norihiro Tanahashi ◽

Tsutomu Kobayashi ◽

Masahide Yamaguchi

Keyword(s):

Second Order ◽

Scalar Tensor Theory ◽

Field Equations ◽

Four Dimensions ◽

Tensor Theory

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Some results in the general scalar tensor theory

Astrophysics and Space Science ◽

10.1007/bf00650169 ◽

1984 ◽

Vol 102 (2) ◽

pp. 223-228

Author(s):

Tarkeshwar Singh ◽

T. Singh

Keyword(s):

Scalar Tensor Theory ◽

Tensor Theory ◽

General Scalar

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Plane Symmetric Solutions of a Scalar-Tensor Theory of Gravitation

Australian Journal of Physics ◽

10.1071/ph770109 ◽

1977 ◽

Vol 30 (1) ◽

pp. 109 ◽

Cited By ~ 6

Author(s):

DRK Reddy

Keyword(s):

General Relativity ◽

Empty Space ◽

Scalar Fields ◽

Scalar Tensor Theory ◽

Field Equations ◽

Plane Symmetric ◽

Zero Mass ◽

Tensor Theory ◽

Special Cases ◽

Theory Of Gravitation

Plane symmetric solutions of a scalar-tensor theory proposed by Dunn have been obtained. These solutions are observed to be similar to the plane symmetric solutions of the field equations corresponding to zero mass scalar fields obtained by Patel. It is found that the empty space-times of general relativity discussed by Taub and by Bera are obtained as special cases.

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Extremal Cosmological Black Holes in Horndeski Gravity and the Anti-Evaporation Regime

Universe ◽

10.3390/universe6110210 ◽

2020 ◽

Vol 6 (11) ◽

pp. 210

Author(s):

Ismael Ayuso ◽

Diego Sáez-Chillón Gómez

Keyword(s):

Black Holes ◽

Black Hole ◽

Cosmological Constant ◽

Linear Order ◽

Scalar Tensor Theory ◽

De Sitter ◽

Tensor Theory ◽

Effective Cosmological Constant ◽

Cosmological Black Holes ◽

Extremal Black Holes

Extremal cosmological black holes are analysed in the framework of the most general second order scalar-tensor theory, the so-called Horndeski gravity. Such extremal black holes are a particular case of Schwarzschild-De Sitter black holes that arises when the black hole horizon and the cosmological one coincide. Such metric is induced by a particular value of the effective cosmological constant and is known as Nariai spacetime. The existence of this type of solutions is studied when considering the Horndeski Lagrangian and its stability is analysed, where the so-called anti-evaporation regime is studied. Contrary to other frameworks, the radius of the horizon remains stable for some cases of the Horndeski Lagrangian when considering perturbations at linear order.

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