Bibliografías temáticas / Horndeski action

Literatura académica sobre el tema "Horndeski action"

Autor: Grafiati
Publicado: 14 de marzo de 2023

Crea una cita precisa en los estilos APA, MLA, Chicago, Harvard y otros

Elija tipo de fuente:

Índice

Consulte las listas temáticas de artículos, libros, tesis, actas de conferencias y otras fuentes académicas sobre el tema "Horndeski action".

Junto a cada fuente en la lista de referencias hay un botón "Agregar a la bibliografía". Pulsa este botón, y generaremos automáticamente la referencia bibliográfica para la obra elegida en el estilo de cita que necesites: APA, MLA, Harvard, Vancouver, Chicago, etc.

También puede descargar el texto completo de la publicación académica en formato pdf y leer en línea su resumen siempre que esté disponible en los metadatos.

Artículos de revistas sobre el tema "Horndeski action"

1

Mironov, S. y V. Volkova. "Properties of perturbations in beyond Horndeski theories". International Journal of Modern Physics A 33, n.º 27 (27 de septiembre de 2018): 1850155. http://dx.doi.org/10.1142/s0217751x18501555.

Texto completo
Resumen
We study whether the approach of Deffayet et al. (DPSV) can be adopted for obtaining a derivative part of quadratic action for scalar perturbations in beyond Horndeski theories about homogeneous and isotropic backgrounds. We find that even though the method does remove the second and higher derivatives of metric perturbations from the linearized Galileon equation, in the same manner as in the general Horndeski theory, it gives incorrect result for the quadratic action. We analyze the reasons behind this property and suggest the way of modifying the approach, so that it gives valid results.
Los estilos APA, Harvard, Vancouver, ISO, etc.
2

Volkova, Victoria. "On perturbations in Horndeski theories". EPJ Web of Conferences 182 (2018): 02127. http://dx.doi.org/10.1051/epjconf/201818202127.

Texto completo
Resumen
This research has been carried out in collaboration with R. Kolevatov, S. Mironov, V. Rubakov and N. Sukhov. We study the approach suggested by Deffayet et al. for obtaining a derivative part of the quadratic action for scalar perturbations in the cubic Horndeski theory. We analyse the validity of the approach and generalize it for the complete Horndeski theory. We explicitly check that the generalized method gives the correct result.
Los estilos APA, Harvard, Vancouver, ISO, etc.
3

Helpin, Thomas y Mikhail S. Volkov. "A metric-affine version of the Horndeski theory". International Journal of Modern Physics A 35, n.º 02n03 (24 de enero de 2020): 2040010. http://dx.doi.org/10.1142/s0217751x20400102.

Texto completo
Resumen
We study the metric-affine versions of scalar-tensor theories whose connection enters the action only algebraically. We show that the connection can be integrated out, resulting in an equivalent metric theory. Specifically, we consider the metric-affine generalisations of the subset of the Horndeski theory whose action is linear in second derivatives of the scalar field. We determine the connection and find that it can describe a scalar-tensor Weyl geometry without a Riemannian frame. Still, as this connection enters the action algebraically, the theory admits the dynamically equivalent (pseudo)-Riemannian formulation in the form of an effective metric theory with an extra K-essence term. This may have interesting phenomenological applications.
Los estilos APA, Harvard, Vancouver, ISO, etc.
4

Hohmann, Manuel. "Disformal Transformations in Scalar–Torsion Gravity". Universe 5, n.º 7 (7 de julio de 2019): 167. http://dx.doi.org/10.3390/universe5070167.

Texto completo
Resumen
We study disformal transformations in the context of scalar extensions to teleparallel gravity, in which the gravitational interaction is mediated by the torsion of a flat, metric compatible connection. We find a generic class of scalar–torsion actions which is invariant under disformal transformations, and which possesses different invariant subclasses. For the most simple of these subclasses we explicitly derive all terms that may appear in the action. We propose to study actions from this class as possible teleparallel analogues of healthy beyond Horndeski theories.
Los estilos APA, Harvard, Vancouver, ISO, etc.
5

Bernardo, Reginald Christian, Jackson Levi Said, Maria Caruana y Stephen Appleby. "Well-tempered Minkowski solutions in teleparallel Horndeski theory". Classical and Quantum Gravity 39, n.º 1 (8 de diciembre de 2021): 015013. http://dx.doi.org/10.1088/1361-6382/ac36e4.

Texto completo
Resumen
Abstract Well-tempering stands among the few classical methods of screening vacuum energy to deliver a late-time, low energy vacuum state. We build on the class of Horndeski models that admit a Minkowski vacuum state despite the presence of an arbitrarily large vacuum energy to obtain a much larger family of models in teleparallel Horndeski theory. We set up the routine for obtaining these models and present a variety of cases, all of which are able to screen a natural particle physics scale vacuum energy using degeneracy in the field equations. We establish that well-tempering is the unique method of utilizing degeneracy in Horndeski scalar-tensor gravity—and its teleparallel generalisation—that can accommodate self-tuned flat Minkowski solutions, when the explicit scalar field dependence in the action is minimal (a tadpole and a conformal coupling to the Ricci scalar). Finally, we study the dynamics of the well-tempered teleparallel Galileon. We generate its phase portraits and assess the attractor nature of the Minkowski vacuum under linear perturbations and through a phase transition of vacuum energy. ‘The effort to understand the Universe is one of the very few things that lifts human life a little above the level of farce, and gives it some of the grace of tragedy.’-Steven Weinberg
Los estilos APA, Harvard, Vancouver, ISO, etc.
6

Vázquez-Báez, V. y C. Ramírez. "Quantum Cosmology of Quadratic f(R) Theories with a FRW Metric". Advances in Mathematical Physics 2017 (2017): 1–5. http://dx.doi.org/10.1155/2017/1056514.

Texto completo
Resumen
We study the quantum cosmology of a quadratic fR theory with a FRW metric, via one of its equivalent Horndeski type actions, where the dynamic of the scalar field is induced. The classical equations of motion and the Wheeler-DeWitt equation, in their exact versions, are solved numerically. There is a free parameter in the action from which two cases follow: inflation + exit and inflation alone. The numerical solution of the Wheeler-DeWitt equation depends strongly on the boundary conditions, which can be chosen so that the resulting wave function of the universe is normalizable and consistent with Hermitian operators.
Los estilos APA, Harvard, Vancouver, ISO, etc.
7

Pardede, Kevin F. S., Agus Suroso y Freddy P. Zen. "Nonlinear matter terms in general scalar–tensor braneworld cosmology". International Journal of Modern Physics D 28, n.º 11 (agosto de 2019): 1950138. http://dx.doi.org/10.1142/s0218271819501384.

Texto completo
Resumen
A five-dimensional braneworld cosmological model in general scalar–tensor action that is comprised of various Horndeski Lagrangians is considered. The Friedmann equations in the case of strongly and weakly coupled [Formula: see text] Horndeski Lagrangians have been obtained. The strongly coupled [Formula: see text] model produces the Cardassian term [Formula: see text] with [Formula: see text], which can serve as an alternative explanation for the accelerated expansion phase of the universe. Furthermore, the latest combined observational facts from BAO, CMB, SNIa, [Formula: see text] and [Formula: see text] value observation suggest that the [Formula: see text] term lies quite close to the constrained value. On the other hand, the weakly coupled [Formula: see text] case has several new correction terms which are omitted in the braneworld Einstein–Hilbert model, e.g. the cubic [Formula: see text] and the dark radiation–matter interaction term [Formula: see text]. Furthermore, this model provides a cosmological constant constructed from the bulk scalar field, requires no brane tension and supports the big bang nucleosynthesis (BBN) constraint naturally.
Los estilos APA, Harvard, Vancouver, ISO, etc.
8

van de Bruck, Carsten y Chris Longden. "Einstein-Gauss-Bonnet Gravity with Extra Dimensions". Galaxies 7, n.º 1 (19 de marzo de 2019): 39. http://dx.doi.org/10.3390/galaxies7010039.

Texto completo
Resumen
We consider a theory of modified gravity possessing d extra spatial dimensions with a maximally symmetric metric and a scale factor, whose ( 4 + d ) -dimensional gravitational action contains terms proportional to quadratic curvature scalars. Constructing the 4D effective field theory by dimensional reduction, we find that a special case of our action where the additional terms appear in the well-known Gauss-Bonnet combination is of special interest as it uniquely produces a Horndeski scalar-tensor theory in the 4D effective action. We further consider the possibility of achieving stabilised extra dimensions in this scenario, as a function of the number and curvature of extra dimensions, as well as the strength of the Gauss-Bonnet coupling. Further questions that remain to be answered such as the influence of matter-coupling are briefly discussed.
Los estilos APA, Harvard, Vancouver, ISO, etc.
9

Gleyzes, Jérôme, David Langlois y Filippo Vernizzi. "A unifying description of dark energy". International Journal of Modern Physics D 23, n.º 13 (noviembre de 2014): 1443010. http://dx.doi.org/10.1142/s021827181443010x.

Texto completo
Resumen
We review and extend a novel approach that we recently introduced, to describe general dark energy or scalar-tensor models. Our approach relies on an Arnowitt-Deser-Misner (ADM) formulation based on the hypersurfaces where the underlying scalar field is uniform. The advantage of this approach is that it can describe in the same language and in a minimal way a vast number of existing models, such as quintessence, F(R) theories, scalar tensor theories, their Horndeski extensions and beyond. It also naturally includes Horava–Lifshitz theories. As summarized in this review, our approach provides a unified treatment of the linear cosmological perturbations about a Friedmann-Lemaître-Robertson-Walker (FLRW) universe, obtained by a systematic expansion of our general action up to quadratic order. This shows that the behavior of these linear perturbations is generically characterized by five time-dependent functions. We derive the full equations of motion in the Newtonian gauge. In the Horndeski case, we obtain the equation of state for dark energy perturbations in terms of these functions. Our unifying description thus provides the simplest and most systematic way to confront theoretical models with current and future cosmological observations.
Los estilos APA, Harvard, Vancouver, ISO, etc.
10

Sebastiani, Lorenzo. "Static spherically symmetric solutions in a subclass of Horndeski theories of gravity". International Journal of Geometric Methods in Modern Physics 15, n.º 09 (8 de agosto de 2018): 1850152. http://dx.doi.org/10.1142/s0219887818501529.

Texto completo
Resumen
In this paper, we will consider a subclass of models of Horndeski theories of gravity and we will check for several Static Spherically Symmetric solutions. We will find a model which admits an exact black hole (BH) solution and we will study its thermodynamics by using the Euclidean Action. We will see that, in analogy with the case of General Relativity (GR), the integration constant of the solution can be identified with the mass of the BH itself. Other solutions will be discussed, by posing special attention on the possibility of reproducing the observed profiles of the rotation curves of galaxies. a
Los estilos APA, Harvard, Vancouver, ISO, etc.
Más fuentes

Tesis sobre el tema "Horndeski action"

1

Bettoni, Dario. "Framing the dark: theory and phenomenology of a non-minimally coupled dark matter fluid". Doctoral thesis, SISSA, 2013. http://hdl.handle.net/20.500.11767/4111.

Texto completo
Resumen
The standard Lambda Cold Dark Matter (ΛCDM) model has proven to be extremely powerful in predicting the evolution and formation of the structure we see in the Universe. However, this success comes at the price of accepting that the energy/matter content of the Universe is dominated by two unknown components: dark matter and dark energy. Moreover, in the case of dark matter some tension between simulations and observations exists at galactic scales, while in the case of dark energy long-standing theoretical issues are still unresolved, thus making the investigation of alternative models a powerful and necessary tool to improve the understanding of the Universe dynamics. In this thesis we study a modified gravity model for dark matter, investigating both its theoretical and phenomenological consequences. In particular, we consider a CDM model in which a dark fluid becomes non-minimally coupled to gravity at recent times and investigate and discuss how this modified picture may be able to address some of the issues the CDM paradigm is facing at small scales, while preserving the successes of the model at large scales. On a more formal level we investigate the properties of the Horndeski action under disformal metric transformation, providing the form of the transformations that leaves it invariant. More than a mathematical curiosity, this invariance represents a first step to formalize some recently notices relations between different models of dark energy, which may be seen as equivalent representation of the same fundamental theory.
Los estilos APA, Harvard, Vancouver, ISO, etc.
También puede estar interesado en las bibliografías ampliadas sobre el tema "Horndeski action" para tipos de fuentes particulares:
Artículos de revistas
Ofrecemos descuentos en todos los planes premium para autores cuyas obras están incluidas en selecciones literarias temáticas. ¡Contáctenos para obtener un código promocional único!

Pasar a la bibliografía