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Related papers: Geometrical aspects on the dark matter problem

200 papers

We analyze some properties of the four dimensional supergravity theories which originate from five dimensions upon reduction. They generalize to N>2 extended supersymmetries the d-geometries with cubic prepotentials, familiar from N=2…

High Energy Physics - Theory · Physics 2015-06-11 Anna Ceresole , Sergio Ferrara , Alessandra Gnecchi , Alessio Marrani

We study second-order cosmological perturbations in scalar-tensor models of dark energy that satisfy local gravity constraints, including f(R) gravity. We derive equations for matter fluctuations under a sub-horizon approximation and…

Astrophysics · Physics 2010-10-12 Takayuki Tatekawa , Shinji Tsujikawa

In this work, we review a plethora of modified theories of gravity with generalized curvature-matter couplings. The explicit nonminimal couplings, for instance, between an arbitrary function of the scalar curvature $R$ and the Lagrangian…

General Relativity and Quantum Cosmology · Physics 2014-07-29 Tiberiu Harko , Francisco S. N. Lobo

We revisit the background solution for scalar matter coupled higher derivative gravity originally reported in arXiv: 1409.8019[hep-th]. In this letter, we choose a convenient ansatz for metric which determines the first order perturbative…

High Energy Physics - Theory · Physics 2016-07-22 Lata Kh Joshi , P. Ramadevi

General 2d dilaton theories, containing spherically symmetric gravity and hence the Schwarzschild black hole as a special case, are quantized by an exact path integral of their geometric (Cartan-) variables. Matter, represented by minimally…

High Energy Physics - Theory · Physics 2009-10-31 W. Kummer , H. Liebl , D. V. Vassilevich

We calculate deviations in cosmological observables as a function of parameters in a class of connection-based models of quantum gravity. In this theory non-trivial modifications to the background cosmology can occur due to a distortion of…

Cosmology and Nongalactic Astrophysics · Physics 2023-02-01 Michael W. Toomey , Savvas Koushiappas , Bruno Alexandre , João Magueijo

The gravitational field of an isolated, axisymmetric flat disk of spinning dust is calculated approximately in the weak-field limit of quasi-metric gravity. Boundary conditions single out the exponential disk as a "preferred" physical…

General Relativity and Quantum Cosmology · Physics 2024-03-26 Dag Østvang

Dark matter caustics have specific density profiles and, therefore, precisely calculable gravitational lensing properties. We present a formalism which simplifies the relevant calculations, and apply it to four specific cases. In the first…

Astrophysics · Physics 2009-11-07 C. Charmousis , V. Onemli , Z. Qiu , P. Sikivie

A simple gravitational model with torsion is studied, and it is suggested that it could explain the dark matter and dark energy in the universe. It can be reinterpreted as a model using the Einstein gravitational equations where spacetime…

General Relativity and Quantum Cosmology · Physics 2022-03-28 Graeme W. Milton

We incorporate the effect of non-local gravitational self-energy to obtain a neutral, non-singular spacetime geometry. This is achieved by using a non-local gravitational theory inspired by T-duality, where particle mass is not point-like…

General Relativity and Quantum Cosmology · Physics 2026-05-04 Kimet Jusufi , Douglas Singleton

We investigate the possibility that the observed behavior of test particles outside galaxies, which is usually explained by assuming the existence of dark matter, is the result of the dynamical evolution of particles in a Weyl type…

General Relativity and Quantum Cosmology · Physics 2024-11-18 Piyabut Burikham , Tiberiu Harko , Kulapant Pimsamarn , Shahab Shahidi

As previously observed the massless limit of massive gravity leads to a modification of general relativity. Here we study spherically symmetric solutions of the modified field equations which contain normal matter together with a dark…

General Relativity and Quantum Cosmology · Physics 2009-02-18 G. Scharf

The cold dark matter model successfully explains both the emergence and evolution of cosmic structures on large scales and, when we include a cosmological constant, the properties of the homogeneous and isotropic Universe. However, the cold…

Cosmology and Nongalactic Astrophysics · Physics 2020-08-04 Ivan de Martino , Sankha S. Chakrabarty , Valentina Cesare , Arianna Gallo , Luisa Ostorero , Antonaldo Diaferio

Redshift space distortions caused by galaxy peculiar velocities provide a window onto the growth rate of large scale structure and a method for testing general relativity. We investigate through a comparison of N-body simulations to various…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 Juliana Kwan , Geraint F. Lewis , Eric V. Linder

Dark matter is one of the pillars of the current standard model of structure formation: it is assumed to constitute most of the matter in the Universe. However, it can so far only be probed indirectly through its gravitational effects, and…

We show how, by considering the cumulative effect of tiny quantum gravitational fluctuations over very large distances, it may be possible to: ($a$) reconcile nucleosynthesis bounds on the density parameter of the Universe with the…

General Relativity and Quantum Cosmology · Physics 2009-10-22 T. Goldman , J. Pérez-Mercader , Fred Cooper , Michael Martin Nieto

We present an efficient numerical algorithm for evolving self-gravitating systems of dark-matter particles that leverages the assumption of spherical symmetry to reduce the nominally six-dimensional phase space to three dimensions. It can…

Astrophysics of Galaxies · Physics 2025-04-22 Marc Kamionkowski , Kris R. Sigurdson

In this thesis, we investigate some aspects of dark matter phenomenology and its predictive power in explaining the flattening of galaxy rotation curves at large distances. After outlining the Standard Model of particle physics, its…

Cosmology and Nongalactic Astrophysics · Physics 2021-08-31 Kirill Zatrimaylov

The universal character of the gravitational interaction provided by the equivalence principle motivates a geometrical description of gravity. The standard formulation of General Relativity \`a la Einstein attributes gravity to the…

General Relativity and Quantum Cosmology · Physics 2021-04-13 Jose Beltrán Jiménez , Lavinia Heisenberg , Tomi Sebastian Koivisto , Simon Pekar

The remarkable range of biological forms in and around us, such as the undulating shape of a leaf or flower in the garden, the coils in our gut, or the folds in our brain, raise a number of questions at the interface of biology, physics and…

General Mathematics · Mathematics 2021-05-13 Marta Lewicka , L. Mahadevan