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We study the constraints that the detection of a non-trivial spatial topology may place on the parameters of braneworld models by considering the Dvali-Gabadadze-Porrati (DGP) and the globally homogeneous Poincar\'e dodecahedral spatial…

Astrophysics · Physics 2016-11-15 M. J. Reboucas

We illustrate the constraints that a possible detection of a non-trivial spatial topology may place on the cosmological density parameters by considering the $\Lambda$CDM model Poincar\'e dodecahedal space (PDS) topology as a…

Astrophysics · Physics 2016-11-15 M. J. Reboucas

Geometry constrains but does not dictate the topology of the 3--dimensional space. In a locally spatially homogeneous and isotropic universe, however, the topology of its spatial section dictates its geometry. We show that, besides…

Astrophysics · Physics 2009-11-11 M. J. Reboucas , J. S. Alcaniz

Two fundamental questions regarding our description of the Universe concern the geometry and topology of its 3-dimensional space. While geometry is a local characteristic that gives the intrinsic curvature, topology is a global feature that…

Astrophysics · Physics 2008-11-26 M. J. Reboucas , J. S. Alcaniz , B. Mota , M. Makler

The accelerating expansion of our universe at present could be driven by an unknown energy component (Dark Energy) or a modification of general relativity (Modified Gravity). In this note we revisit the constraints on a phenomenological…

Cosmology and Nongalactic Astrophysics · Physics 2009-08-03 Jun-Qing Xia

In this work we study to which extent the knowledge of spatial topology may place constraints on the parameters of the generalized Chaplygin gas (GCG) model for unification of dark energy and dark matter. By using both the Poincar\'e…

General Relativity and Quantum Cosmology · Physics 2008-11-26 M. C. Bento , O. Bertolami , M. J. Rebouças , P. T. Silva

Applying the definition of the turnaround radius and the fact that the best agreement with observational data on extragalactic scales is currently provided by general relativity with the cosmological constant we consider the behaviour of…

General Relativity and Quantum Cosmology · Physics 2025-03-26 Oleg Zenin , Stanislav Alexeyev

General relativity does not allow one to specify the topology of space, leaving the possibility that space is multiply rather than simply connected. We review the main mathematical properties of multiply connected spaces, and the different…

Astrophysics · Physics 2007-05-23 Jean-Pierre Luminet

We study one of the simplest covariant modified-gravity models based on the Dvali-Gabadadze-Porrati (DGP) brane cosmology, a self-accelerating universe. In this model gravitational leakage into extra dimensions is responsible of late-time…

Astrophysics · Physics 2009-04-08 M. Sadegh Movahed , Marzieh Farhang , Sohrab Rahvar

A nontrivial topology of the spatial section of the universe is an observable, which can be probed for all locally homogeneous and isotropic universes, without any assumption on the cosmological density parameters. We discuss how one can…

Astrophysics · Physics 2008-11-26 M. J. Reboucas

It is well-known that allowing for spatial curvature affects constraints on cosmological parameters such as the dark energy equation of state parameters. Here we study the effect of curvature on constraints on parameters used to test…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-30 Jason Dossett , Mustapha Ishak

We compare a large suite of theoretical cosmological models to observational data from the cosmic microwave background, baryon acoustic oscillation measurements of expansion, Type Ia SNe measurements of expansion, redshift space distortion…

Cosmology and Nongalactic Astrophysics · Physics 2017-12-13 Zhongxu Zhai , Michael Blanton , Anže Slosar , Jeremy Tinker

We investigate observational constraints on the Dvali, Gabadadze and Porrati (DGP) model with Gamma-ray bursts (GRBs) at high redshift obtained directly from the Union2 Type Ia supernovae data (SNe Ia) set. With the cosmology-independent…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-17 Nan Liang , Zong-Hong Zhu

We perform a Markov Chain Monte Carlo analysis of the self-accelerating and normal branch of Dvali-Gabadadze-Porrati braneworld gravity. By adopting a parameterized post-Friedmann description of gravity, we utilize all of the cosmic…

Cosmology and Nongalactic Astrophysics · Physics 2010-04-15 Lucas Lombriser , Wayne Hu , Wenjuan Fang , Uros Seljak

In this work, we use observations of the Hubble parameter from the differential ages of passively evolving galaxies and the recent detection of the Baryon Acoustic Oscillations (BAO) at $z_1=0.35$ to constrain the Dvali-Gabadadze-Porrati…

Astrophysics · Physics 2008-11-26 Hao-Yi Wan , Ze-Long Yi , Tong-Jie Zhang , Jie Zhou

Reconstructing the expansion history of the Universe from type Ia supernovae data, we fit the growth rate measurements and put model-independent constraints on some key cosmological parameters, namely, $\Omega_\mathrm{m},\gamma$, and…

Cosmology and Nongalactic Astrophysics · Physics 2018-05-10 Benjamin L'Huillier , Arman Shafieloo , Hyungjin Kim

In this paper we place new constraints on a f(R) modified gravity model recently proposed by Hu and Sawicki. After checking that the Hu and Sawicki model produces a viable cosmology, i.e. a matter dominated epoch followed by a late-time…

Cosmology and Nongalactic Astrophysics · Physics 2009-07-09 Matteo Martinelli , Alessandro Melchiorri , Luca Amendola

We investigate the imprints of the Generalized Uncertainty Principle on cosmological scales by using redshift-space distortion measurements in combination with background cosmological data to determine constraints on the deformation…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-03 Andronikos Paliathanasis

There are several studies proposing phenomenological consequences of a deformation of special and general relativity. Here, we cast novel constraints on the deformation parameter of a metric in the cotangent bundle accounting for a curved…

General Relativity and Quantum Cosmology · Physics 2020-11-18 J. J. Relancio , S. Liberati

In this paper we discuss the restrictions of the spacetime for the standard model of cosmology by using results of the differential topology of 3- and 4-manifolds. The smoothness of the cosmic evolution is the strongest restriction. The…

General Relativity and Quantum Cosmology · Physics 2012-07-27 T. Asselmeyer-Maluga , J. Krol
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