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Related papers: New Minimal Distortion Shift Gauge

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Combining redshift and galaxy shape information offers new exciting ways of exploiting the gravitational lensing effect for studying the large scales of the cosmos. One application is the three-dimensional reconstruction of the matter…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 Patrick Simon , Andy Taylor , Jan Hartlap

We find a choice of variables for the 3+1 formulation of general relativity which casts the evolution equations into (flux-conservative) symmetric-hyperbolic first order form for arbitrary lapse and shift, for the first time. We redefine…

General Relativity and Quantum Cosmology · Physics 2009-10-28 Simonetta Frittelli , Oscar Reula

In inverse optimization problems, the goal is to modify the costs in an underlying optimization problem in such a way that a given solution becomes optimal, while the difference between the new and the original cost functions, called the…

Optimization and Control · Mathematics 2023-03-01 Kristóf Bérczi , Lydia Mirabel Mendoza-Cadena , Kitti Varga

We review and extend the Gauge Vectors-Tensor gravity: a covariant theory of gravity composed of a metric and gauge fields, leading to simple second order partial differential equations of motion, whose Newtonian and strong limits coincide…

General Relativity and Quantum Cosmology · Physics 2014-06-03 Qasem Exirifard

This work discusses a variational approach to determining the time evolution operator. We directly see a glimpse of how a generalization of the quantum geometric tensor for unitary operators plays a central role in parameter evolution. We…

Quantum Physics · Physics 2025-04-15 Michael Vogl

We present a general approach to the analysis of gauge stability of 3+1 formulations of General Relativity (GR). Evolution of coordinate perturbations and the corresponding perturbations of lapse and shift can be described by a system of…

General Relativity and Quantum Cosmology · Physics 2009-11-07 A. M Khokhlov , I. D. Novikov

It is well known that the Einstein-Hilbert action in two dimensions is topological and yields an identically vanishing Einstein tensor. Consequently one is faced with difficulties when formulating a non-trivial gravity model. We present a…

General Relativity and Quantum Cosmology · Physics 2024-06-10 Christian G. Boehmer , Erik Jensko

Quantum gravity theories predict a minimal length at the order of magnitude of the Planck length, under which the concepts of space and time lose every physical meaning. In quantum mechanics, the insurgence of such minimal length can be…

Quantum Physics · Physics 2016-07-08 Matteo A. C. Rossi , Tommaso Giani , Matteo G. A. Paris

Suitable gauge conditions are fundamental for stable and accurate numerical-relativity simulations of inspiralling compact binaries. A number of well-studied conditions have been developed over the last decade for both the lapse and the…

General Relativity and Quantum Cosmology · Physics 2010-12-06 Daniela Alic , Luciano Rezzolla , Ian Hinder , Philipp Mösta

A minimal observable length is a common feature of theories that aim to merge quantum physics and gravity. Quantum mechanically, this concept is associated to a nonzero minimal uncertainty in position measurements, which is encoded in…

In this thesis, I investigate how to construct a self-consistent model of deformed general relativity using canonical methods and metric variables. The specific deformation of general covariance is predicted by some studies into loop…

General Relativity and Quantum Cosmology · Physics 2019-10-07 Rhiannon Cuttell

To test the theory of gravity one needs to test, on one hand, how space and time are distorted by matter and, on the other hand, how matter moves in a distorted space-time. Current observations provide tight constraints on the motion of…

Cosmology and Nongalactic Astrophysics · Physics 2023-06-09 Daniel Sobral-Blanco , Camille Bonvin

Within a gauge formulation of 3+1 gravity relying on a nonlinear realization of the group of isometries of space-time, a natural expansion of the metric tensor arises and a simple choice of the gravity dynamical variables is possible. We…

General Relativity and Quantum Cosmology · Physics 2016-11-09 J. Julve , A. Tiemblo

A physics-first derivation of the Schwarzschild metric is given. Gravitation is described in terms of the effects of tidal forces (or of spacetime curvature) on the volume of a small ball of test particles (a dust ball), freely falling…

General Relativity and Quantum Cosmology · Physics 2017-07-20 Klaus Kassner

A successful measurement of the Stochastic Gravitational Wave Background (SGWB) in Pulsar Timing Arrays (PTAs) would open up a new window through which to test the predictions of General Relativity (GR). We consider how these measurements…

Cosmology and Nongalactic Astrophysics · Physics 2025-05-29 Qiuyue Liang , Meng-Xiang Lin , Mark Trodden

By considering a deformation of the Schwarzschild metric in the presence of a minimal measurable length which still respects the equivalence principle, we study corrections to the standard general relativistic predictions for some…

General Relativity and Quantum Cosmology · Physics 2017-06-22 Mohsen Khodadi , Kourosh Nozari , Anahita Hajizadeh

In this work, we study various properties of embedded hypersurfaces in $1+1+2$ decomposed spacetimes with a preferred spatial direction, denoted $e^{\mu}$, which are orthogonal to the fluid flow velocity of the spacetime and admit a proper…

Differential Geometry · Mathematics 2022-03-17 Abbas M. Sherif , Peter K. S. Dunsby

If the Einstein-Hilbert action ${\cal L}_{\rm EH}\propto R$ is re-expressed in Riemann-Cartan spacetime using the gauge fields of translations, the vierbein field $h^\alpha{}_\mu$, and the gauge field of local Lorentz transformations, the…

General Relativity and Quantum Cosmology · Physics 2017-08-23 H. Kleinert

The starting point of this work is the original Einstein action, sometimes called the Gamma squared action. Continuing from our previous results, we study various modified theories of gravity following the Palatini approach. The metric and…

General Relativity and Quantum Cosmology · Physics 2023-09-29 Christian G. Boehmer , Erik Jensko

We compute the one-loop divergences in a higher-derivative theory of gravity including Ricci tensor squared and Ricci scalar squared terms, in addition to the Hilbert and cosmological terms, on an (generally off-shell) Einstein background.…

High Energy Physics - Theory · Physics 2017-10-25 N. Ohta , R. Percacci , A. D. Pereira