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Stability of braneworlds with non-minimally coupled multi-scalar fields
European Physical Journal C: Particles and Fields, 2018 Linear stability of braneworld models constructed with multi-scalar fields is very different from that of single-scalar field models. It is well known that both the tensor and the scalar perturbations of the latter are stable at linear level. However, in
Feng-Wei Chen, Bao-Min Gu, Yu-Xiao Liu
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SCALAR PERTURBATIONS IN f(R)-COSMOLOGIES
Odessa Astronomical Publications, 2013 We take first steps to generalizing the recently developed mechanical (non-hydrodynamical), or discrete (discontinuous), approach to cosmological problems on intermediate, semiastrophysical semicos- mological, scales to the case of nonlinear gravity.
M. Eingorn, J. Novak
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Ghost instability in the teleparallel gravity model with parity violations
Physics Letters B, 2022 In this paper we consider the parity violating gravity model within the framework of teleparallel gravity. The parity violations are caused by the couplings of a scalar field to the scalar invariants which are parity-odd and quadratic in the torsion ...
Mingzhe Li, Zhihao Li, Haomin Rao
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Perturbation theory and non-renormalizable scalar fields [PDF]
Communications in Mathematical Physics, 1986 Our main result is that it is possible to express the Schwinger functions (or the effective potentials) as formal power series of objects which we call ''form factors'' which, although divergent to all orders of perturbation theory if the cut-off N is removed, obey to all orders a formal equation which retains its meaning as \(N\to \infty\).
Felder, Giovanni, Gallavotti, Giovanni
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Thick branes with inner structure in mimetic gravity
European Physical Journal C: Particles and Fields, 2018 In this paper, thick branes generated by mimetic scalar field are investigated. Three typical thick brane models are constructed and the linear tensor and scalar perturbations are analyzed.
Yi Zhong +3 more
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Holographic CFT states for localized perturbations to AdS black holes
Journal of High Energy Physics, 2019 In this note, we describe a holographic CFT construction of states dual to scalar perturbations of the maximally extended three-dimensional AdS-Schwarzschild black hole.
Hong Zhe Chen, Mark Van Raamsdonk
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Strong Cosmic Censorship in higher-dimensional Reissner-Nordström-de Sitter spacetime
Journal of High Energy Physics, 2019 : It was recently shown that Strong Cosmic Censorship might be violated for near-extremally-charged black holes in 4-dimensional de Sitter space under scalar perturbations.
Hang Liu +5 more
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Nonlinear preheating with scalar metric perturbations [PDF]
Physical Review D, 2008 15 pages, 12 eps ...
Bastero-Gil, M. +3 more
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Scalar and spinor perturbation to the Kerr–NUT spacetime [PDF]
Classical and Quantum Gravity, 2004 We study the scalar and spinor perturbation, namely the Klein-Gordan and Dirac equations, in the Kerr-NUT space-time. The metric is invariant under the duality transformation involving the exchange of mass and NUT parameters on one hand and radial and angle coordinates on the other.
Mukhopadhyay, Banibrata, Dadhich, Naresh
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Scalar Cosmological Perturbations
, 2020 In this paper we present the study of the scalar cosmological perturbations of a single field inflationary model up to first order in deviation. The Christoffel symbols and the tensorial quantities are calculated explicitly in function of the cosmic time t.
Tapia, Truman, Rojas, Clara
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