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Related papers: New Classes of Off-Diagonal Cosmological Solutions…

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We re-investigate how generic off-diagonal cosmological solutions depending, in general, on all spacetime coordinates can be constructed in massive and f-modified gravity using the anholonomic frame deformation method. There are constructed…

General Relativity and Quantum Cosmology · Physics 2015-05-06 Sergiu I. Vacaru

Using our anholonomic frame deformation method, we show how generic off-diagonal cosmological solutions depending, in general, on all spacetime coordinates and undergoing a phase of ultra-slow contraction can be constructed in massive…

High Energy Physics - Theory · Physics 2017-06-05 Sergiu I. Vacaru

Modified gravity theories (MGTs) have long been studied as alternatives to general relativity (GR) and the standard Lambda CDM cosmological model. For example, exponential f(R) models often yield better fits to observational data,…

General Physics · Physics 2026-05-01 Sergiu I. Vacaru

This article is a status report on the Anholonomic Frame and Connection Deformation Method, AFCDM, for constructing generic off-diagonal exact and parametric solutions in general relativity, GR, relativistic geometric flows, and modified…

General Relativity and Quantum Cosmology · Physics 2025-10-07 Laurenţiu Bubuianu , Julia O. Seti , Douglas Singleton , Panayiotis Stavrinos , Sergiu I. Vacaru , Elşen Veli Veliev

We formulate an approach to the geometry of Riemann-Cartan spaces provided with nonholonomic distributions defined by generic off-diagonal and nonsymmetric metrics inducing effective nonlinear and affine connections. Such geometries can be…

General Relativity and Quantum Cosmology · Physics 2008-12-19 Sergiu I. Vacaru

A generalized geometric method is developed for constructing exact solutions of gravitational field equations in Einstein theory and generalizations. First, we apply the formalism of nonholonomic frame deformations (formally considered for…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Sergiu I. Vacaru

We show how generic off--diagonal cosmological solutions depending, in general, on all spacetime coordinates can be constructed in massive gravity using the anholonomic frame deformation method. Such metrics describe the late time…

General Relativity and Quantum Cosmology · Physics 2015-02-23 Sergiu I. Vacaru

We show how the Einstein equations with cosmological constant (and/or various types of matter field sources) can be integrated in a very general form following the anholonomic deformation method for constructing exact solutions in four and…

General Physics · Physics 2017-10-19 Sergiu I. Vacaru

It is formulated a new 'anholonomic frame' method of constructing exact solutions of Einstein equations with off--diagonal metrics in 4D and 5D gravity. The previous approaches and results are summarized and generalized as three theorems…

High Energy Physics - Theory · Physics 2007-05-23 Sergiu I. Vacaru

The anholonomic frame method is generalized for non--Riemannian gravity models defined by string corrections to the general relativity and metric-affine gravity (MAG) theories. Such spacetime configurations are modeled as metric-affine…

High Energy Physics - Theory · Physics 2007-05-23 Sergiu I. Vacaru , Evghenii Gaburov , Denis Gontsa

By applying the method of moving frames modelling one and two dimensional local anisotropies we construct new solutions of Einstein equations on pseudo-Riemannian spacetimes. The first class of solutions describes non-trivial deformations…

General Relativity and Quantum Cosmology · Physics 2016-08-31 Sergiu I. Vacaru

We prove that the Einstein equations can be solved in a very general form for arbitrary spacetime dimensions and various types of vacuum and non-vacuum cases following a geometric method of anholonomic frame deformations for constructing…

General Relativity and Quantum Cosmology · Physics 2014-11-20 Sergiu I. Vacaru

In this article we consider nonholonomic deformations of disk solutions in general relativity to generic off-diagonal metrics defining knew classes of exact solutions in 4D and 5D gravity. These solutions possess Lie algebroid symmetries…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Sergiu I. Vacaru

Certain off-diagonal vacuum and nonvacuum configurations in Einstein gravity can mimic physical effects of modified gravitational theories of $ f(R,T,R_{\mu\nu}T^{\mu\nu})$ type. We prove this statement by constructing exact and approximate…

Mathematical Physics · Physics 2015-06-30 Emilio Elizalde , Sergiu I. Vacaru

Off-diagonal vacuum and nonvacuum configurations in Einstein gravity can mimic physical effects of modified gravitational theories of $f(R,T,R_{\mu \nu}T^{\mu \nu})$ type. To prove this statement, exact and approximate solutions are…

General Relativity and Quantum Cosmology · Physics 2015-07-01 Emilio Elizalde , Sergiu I. Vacaru

The 'anholonomic frame' method (see gr-qc/0005025, gr-qc/0001060 and hep-th/0110250) is applied for constructing new classes of exact solutions of vacuum Einstein equations with off-diagonal metrics in 4D and 5D gravity. We examine several…

High Energy Physics - Theory · Physics 2007-05-23 Sergiu I. Vacaru

We analyze local anisotropies induced by anholonomic frames and associated nonlinear connections in general relativity and extensions to affine Poincare and de Sitter gauge gravity and different types of Kaluza-Klein theories. We construct…

General Relativity and Quantum Cosmology · Physics 2015-06-25 Sergiu I. Vacaru , Heinz Dehnen

The goal of this work is to elaborate on new geometric methods of constructing exact and parametric quasiperiodic solutions for anamorphic cosmology models in modified gravity theories, MGTs, and general relativity, GR. There exist…

General Relativity and Quantum Cosmology · Physics 2017-10-24 Marcelo M. Amaral , Raymond Aschheim , Laurenţiu Bubuianu , Klee Irwin , Sergiu I. Vacaru , Daniel Woolridge

We use an important decoupling property of gravitational field equations in the general relativity theory and modifications, written with respect to nonholonomic frames with 2+2 spacetime decomposition. This allows us to integrate the…

General Physics · Physics 2013-03-18 Sergiu I. Vacaru

There are explored off-diagonal deformations of "prime" metrics in Einstein gravity (for instance, for wormhole configurations) into "target" exact solutions in f(R,T)-modified and massive/ bi-metric gravity theories. The new classes of…

General Relativity and Quantum Cosmology · Physics 2014-03-25 Sergiu I. Vacaru
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