Results 11 to 20 of about 1,900 (308)
Spontaneous scalarization in generalized scalar-tensor theory [PDF]
Physical Review D, 2019 Spontaneous scalarization is a mechanism that endows relativistic stars and black holes with a nontrivial configuration only when their spacetime curvature exceeds some threshold. The standard way to trigger spontaneous scalarization is via a tachyonic instability at the linear level, which is eventually quenched due to the effect of non-linear terms ...
Andreou, Nikolas +3 more
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Higher dimensional black hole scalarization [PDF]
Journal of High Energy Physics, 2020 In the simplest scalar-tensor theories, wherein the scalar field is non-minimally coupled to the Ricci scalar, spontaneous scalarization of electrovacuum black holes (BHs) does not occur. This ceases to be true in higher dimensional spacetimes, d > 4. We
Dumitru Astefanesei +3 more
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qOS-induced scalarization of black holes in extended scalar-tensor theories
Physics Letters BIn the extended scalar-tensor-Gauss-Bonnet (ESTGB) theory, spontaneous scalarization has been extensively studied in various types of black holes.
Lu Chen, Shun Jiang
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Horizon curvature and spacetime structure influences on black hole scalarization
European Physical Journal C: Particles and Fields, 2021 Black hole spontaneous scalarization has been attracting more and more attention as it circumvents the well-known no-hair theorems. In this work, we study the scalarization in Einstein–scalar-Gauss–Bonnet theory with a probe scalar field in a black hole ...
Hong Guo +3 more
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Scalar-connection gravity and spontaneous scalarization [PDF]
Physical Review D, 2021 Scalar-tensor theories of gravity are known to allow significant deviations from general relativity through various astrophysical phenomena. In this paper, we formulate a scalar-connection gravity by setting up scalars and connection configurations instead of metric. Since the matter sector is not straightforward to conceive without a metric, we invoke
Hemza Azri, Salah Nasri
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Journal of Semantics, 2014 We present experimental evidence showing that there is considerable variation between the rates at which scalar expressions from different lexical scales give rise to Upper-Bounded construals. We investigated two factors that might explain the variation between scalar expressions: first, the availability of the lexical scales, which we measured on the ...
Bob van Tiel +3 more
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Scalar glueball, scalar quarkonia, and their mixing [PDF]
Physical Review D, 2006 The isosinglet scalar mesons $f_0(1710)$, $f_0(1500)$, $f_0(1370)$ and their mixing are studied. We employ two recent lattice results as the starting point; one is the isovector scalar meson $a_0(1450)$ which displays an unusual property of being nearly independent of quark mass for quark masses smaller than that of the strange, and the other is the ...
Cheng, Hai-Yang +2 more
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Scalar–tensor theories with an external scalar [PDF]
General Relativity and Gravitation, 2016 Scalar-tensor (ST) gravity is considered in the case where the scalar is an external field. We show that General Relativity (GR) and usual ST gravity are particular cases of the External Scalar-Tensor (EST) gravity. It is shown with a particular cosmological example that it is possible to join a part of a GR solution to a part of a ST one such that the
Chauvineau, Bertrand +2 more
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Journal of Cosmology and Astroparticle Physics, 2020 We provide a complete classification of Poincar'e-invariant scalar field theories with an enlarged set of classical symmetries to leading order in derivatives, namely for the so-called P(X,ϕ) theories, in two or more spacetime dimensions. We find only three possibilities: Dirac-Born-Infeld, Cuscuton and Scaling theories.
Grall, Tanguy +2 more
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Scalar perturbations in scalar field quantum cosmology [PDF]
Physical Review D, 2009 In this paper it is shown how to obtain the simplest equations for the Mukhanov-Sasaki variables describing quantum linear scalar perturbations in the case of scalar fields without potential term. This was done through the implementation of canonical transformations at the classical level, and unitary transformations at the quantum level, without ever ...
Falciano, F. T., Pinto-Neto, Nelson
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