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We consider the most general action for gravity which is quadratic in curvature. In this case first order and second order formalisms are not equivalent. This framework is a good candidate for a unitary and renormalizable theory of the…

High Energy Physics - Theory · Physics 2017-12-22 Enrique Alvarez , Jesus Anero , Sergio Gonzalez-Martin

We present cylindrically symmetric solutions for a type of the Gauss-Bonnet gravity, in details. We derive the full system of the field equations and show that there exist seven families of exact solutions for three forms of viable models.…

General Relativity and Quantum Cosmology · Physics 2015-06-12 M. J. S. Houndjo , M. E. Rodrigues , D. Momeni , R. Myrzakulov

Gauss-Bonnet gravity provides one of the most promising frameworks to study curvature corrections to the Einstein action in supersymmetric string theories, while avoiding ghosts and keeping second order field equations. Although…

General Relativity and Quantum Cosmology · Physics 2008-11-26 S. Alexeyev , N. Popov , M. Startseva , A. Barrau , J. Grain

The paper investigates the approximation of the symmetric Total Variation functional on graphs. Such an approximation is given in terms of a discrete and symmetric finite difference model defined on point clouds obtained by randomly…

Analysis of PDEs · Mathematics 2026-03-31 Stefano Almi , Anna Kubin , Emanuele Tasso

We use the covariant formulation proposed in Tattersall et al (2017) to analyse the structure of linear perturbations about a spherically symmetric background in different families of gravity theories, and hence study how quasi-normal modes…

General Relativity and Quantum Cosmology · Physics 2018-02-21 Oliver J. Tattersall , Pedro G. Ferreira , Macarena Lagos

In this review we present the theoretical background for treating General Relativity as an effective field theory and focus on the concrete results of such a treatment. As a result we present the calculations of the low-energy leading…

General Relativity and Quantum Cosmology · Physics 2010-12-24 Arif Akhundov , Anwar Shiekh

An extension of the Gauss-Newton algorithm is proposed to find local minimizers of penalized nonlinear least squares problems, under generalized Lipschitz assumptions. Convergence results of local type are obtained, as well as an estimate…

Optimization and Control · Mathematics 2011-03-03 Saverio Salzo , Silvia Villa

We extend the theory of the gauging of classical quadratically nonlinear algebras without a central charge but with a coset structure, to the quantum level. Inserting the minimal anomalies into the classical transformation rules of the…

High Energy Physics - Theory · Physics 2011-07-19 A. Sevrin , P. van Nieuwenhuizen

We discuss various aspects of the post-Newtonian approximation in general relativity. After presenting the foundation based on the Newtonian limit, we use the (3+1) formalism to formulate the post-Newtonian approximation for the perfect…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Hideki Asada , Toshifumi Futamase

In this paper, a variable-coefficient Gardner equation is considered. By using the classical symmetry analysis method symmetries for this equation are obtained. Then, the generalized Jacobi elliptic function expansion method is used to…

Exactly Solvable and Integrable Systems · Physics 2010-02-23 M. S. Abdel Latif

A new method of approximation scheme with potential application to a general interacting quantum system is presented. The method is non-perturbative, self- consistent, systematically improvable and uniformly applicable for arbitrary…

Quantum Physics · Physics 2008-06-13 Nabaghan Santi

In the asymptotic safety programme for quantum gravity, it is important to go beyond polynomial truncations. Three such approximations have been derived where the restriction is only to a general function f(R) of the curvature R>0. We…

High Energy Physics - Theory · Physics 2013-01-29 Juergen A. Dietz , Tim R. Morris

We show the equivalence between the three approximation schemes for self-interacting (1+1)-D scalar field theories. Based on rigorous results of [1, 2], we are able to prove that the Gaussian approximation is very precise for certain limits…

Quantum Physics · Physics 2007-05-23 E. Prodan

We construct the most general, to cubic order in curvature, theory of gravity whose (most general) static spherically symmetric vacuum solutions are fully described by a single field equation. The theory possess the following remarkable…

High Energy Physics - Theory · Physics 2017-06-07 Robie A. Hennigar , David Kubiznak , Robert B. Mann

It is shown that quadrature formulas in many different applications can be derived from rational approximation of the Cauchy transform of a weight function. Since rational approximation is now a routine technology, this provides an easy new…

Numerical Analysis · Mathematics 2025-07-22 Andrew Horning , Lloyd N. Trefethen

This is a brief tutorial on the least square estimation technique that is straightforward yet effective for parameter estimation. The tutorial is focused on the linear LSEs instead of nonlinear versions, since most nonlinear LSEs can be…

Systems and Control · Electrical Eng. & Systems 2022-11-29 Qingrui Zhang

This paper pursues a twofold goal. First, we introduce and study in detail a new notion of variational analysis called generalized metric subregularity, which is a far-going extension of the conventional metric subregularity conditions. Our…

Optimization and Control · Mathematics 2024-06-21 Guoyin Li , Boris Mordukhovich , Jiangxing Zhu

We consider a variant of the art gallery problem where all guards are limited to seeing to the right inside a monotone polygon. We call such guards: half-guards. We provide a polynomial-time approximation for point guarding the entire…

Computational Geometry · Computer Science 2022-04-29 Hannah Miller Hillberg , Erik Krohn , Alex Pahlow

Resource-efficient and high-precision approximate synthesis of quantum circuits expressed in the Clifford+T gate set is vital for Fault-Tolerant quantum computing. Efficient optimal methods are known for single-qubit RZ unitaries, otherwise…

Quantum Physics · Physics 2026-04-27 Mathias Weiden , Justin Kalloor , John Kubiatowicz , Ed Younis , Costin Iancu

We analyse the accuracy of the approximate WKB quantization for the case of general one-dimensional quartic potential. In particular, we are interested in the validity of semiclassically predicted energy eigenvalues when approaching the…

Chaotic Dynamics · Physics 2009-10-31 Marko Vranicar , Marko Robnik