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Arbitrary generalization to the teleparallel equivalent of general relativity loses local Lorentz invariance to reparametrize the orthonormal coordinate system and gives rise to asymmetry field equations. We investigate consequences of…

General Relativity and Quantum Cosmology · Physics 2016-11-07 Yi-Peng Wu

We investigate inflation in modified teleparallel gravity within a scalar-tensor framework. We focus on two viable extensions of the Teleparallel Equivalent of General Relativity: a power-law model and an exponential model, which introduce…

General Relativity and Quantum Cosmology · Physics 2026-04-28 Daniel Villalobos-Silva , Yerko Vásquez , Giovanni Otalora

We examine the generation of primordial perturbations during an inflationary epoch in generalised theories of gravity when the equations of motion are derived using the Palatini variational principle. Both f(R) and Scalar-Tensor theories…

General Relativity and Quantum Cosmology · Physics 2011-02-18 Nicola Tamanini , Carlo R. Contaldi

We study slow-roll inflation and the generation of primordial fluctuations in $F(T)$ gravity's rainbow. We obtain the second order action for scalar and tensor perturbations and then calculate the primordial power spectrum for them. Thus,…

General Relativity and Quantum Cosmology · Physics 2022-02-18 Yoelsy Leyva , Carlos Leiva , Giovanni Otalora , Joel Saavedra

Teleparallel Gravity is a gauge theory where gravity is a manifestation of the torsion of space-time and its success relies on being a possible solution to some problems of General Relativity. In this essay we introduce the construction of…

General Relativity and Quantum Cosmology · Physics 2023-05-12 Geovanny A. Rave-Franco , Celia Escamilla-Rivera

Supersolid inflation is a class of inflationary theories that simultaneously breaks time and space reparameterization invariance during inflation, with distinctive features for the dynamics of cosmological fluctuations. We investigate…

Cosmology and Nongalactic Astrophysics · Physics 2017-07-19 Angelo Ricciardone , Gianmassimo Tasinato

We investigate slow roll inflation and the creation of primordial density fluctuations in the framework of $f(Q,T)$ gravity. Our focus is on constraining the evolution of both the background and perturbations in this theory, specifically…

General Relativity and Quantum Cosmology · Physics 2026-02-09 Parviz Goodarzi

We investigate primordial gravitational waves and curvature perturbations in de Rham-Gabadadze-Tolley (dRGT) bimetric gravity. We evaluate the power-spectra in the leading order in slow roll. Taking into account the decay of massive…

High Energy Physics - Theory · Physics 2016-10-17 Yuki Sakakihara , Takahiro Tanaka

In the semi-classical regime, quantum fluctuations embedded in a Riemannian spacetime can be effectively recast as classical back reactions and manifest themselves in the form of non-minimal couplings between matter and curvature. In this…

General Relativity and Quantum Cosmology · Physics 2022-02-07 Che-Yu Chen , Yu-Hsien Kung

It is investigated the reconstruction during the slow-roll inflation in the most general class of scalar-torsion theories whose Lagrangian density is an arbitrary function $f(T,\phi)$ of the torsion scalar $T$ of teleparallel gravity and…

General Relativity and Quantum Cosmology · Physics 2021-08-17 Manuel Gonzalez-Espinoza , Ramón Herrera , Giovanni Otalora , Joel Saavedra

We investigate modified theories of gravity in the context of teleparallel geometries. It is well known that modified gravity models based on the torsion scalar are not invariant under local Lorentz transformations while modifications based…

General Relativity and Quantum Cosmology · Physics 2015-11-30 Sebastian Bahamonde , Christian G. Boehmer , Matthew Wright

We explore the generation of large-scale magnetic fields from inflation in teleparallelism, in which the gravitational theory is described by the torsion scalar instead of the scalar curvature in general relativity. In particular, we…

Cosmology and Nongalactic Astrophysics · Physics 2012-11-02 Kazuharu Bamba , Chao-Qiang Geng , Ling-Wei Luo

Nonlinear generalizations of teleparallel gravity entail the modification of a Lagrangian that is pseudoinvariant under local Lorentz transformations of the tetrad field. This procedure consequently leads to the loss of the local…

General Relativity and Quantum Cosmology · Physics 2020-04-27 Rafael Ferraro , María José Guzmán

It is believed that the recent detection of large tensor perturbations strongly favors the inflation scenario in the early universe. This common sense depends on the assumption that Einstein's general relativity is valid at the early…

High Energy Physics - Theory · Physics 2015-06-19 Mingzhe Li

The review is devoted to consideration of possible observational consequences of modified gravity theories, suggested for explanation of the contemporary accelerated expansion of the universe. The major attention is paid to F(R)-models. It…

General Relativity and Quantum Cosmology · Physics 2019-11-11 Elena Arbuzova

We consider primordial fluctuations in thermal inflation scenario. Since the thermal inflation drives about 10 $e$-folds after the standard inflation, the time of horizon-exit during inflation corresponding to the present observational…

High Energy Physics - Theory · Physics 2010-02-18 Masahiro Kawasaki , Tomo Takahashi , Shuichiro Yokoyama

We study the dynamics of inflation in a generalized scalar-torsion gravity scenario by assuming a canonical scalar field non-minimally coupled to torsion with a Galileon-type self-interaction. After obtaining the field equations for a flat…

General Relativity and Quantum Cosmology · Physics 2019-08-26 Manuel Gonzalez-Espinoza , Giovanni Otalora , Nelson Videla , Joel Saavedra

We study logamediate inflation in the context of $f(T)$ teleparallel gravity. $f(T)$-gravity is a generalization of the teleparallel gravity which is formulated on the Weitzenb\"{o}ck spacetime, characterized by the vanishing curvature…

General Relativity and Quantum Cosmology · Physics 2017-02-28 Kazem Rezazadeh , Asrin Abdolmaleki , Kayoomars Karami

We propose a new mechanism to generate primordial curvature perturbations, based on the resonant production of particles during inflation. It is known that this phenomenon can trap the inflaton for a fraction of e-fold. This effect is…

Cosmology and Nongalactic Astrophysics · Physics 2009-08-17 David Langlois , Lorenzo Sorbo

The physical properties of our universe at energy scales above the expansion rate during inflation can affect predictions for the ratio between the amplitudes of the primordial scalar and tensor fluctuations. In particular, we study here…

High Energy Physics - Phenomenology · Physics 2008-11-03 Hael Collins
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