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The unified generalized non-local quantum kinetic and hydrodynamic theory is applied for mathematical modeling of objects in the giant scale diapason from the galaxy and Universe scale to atom structures. The principle of universal…

General Physics · Physics 2012-03-13 Boris V. Alexeev

We consistently quantize a class of relativistic non-local field equations characterized by a non-local kinetic term in the lagrangian. We solve the classical non-local equations of motion for a scalar field and evaluate the on-shell…

High Energy Physics - Theory · Physics 2015-06-26 D. G. Barci , L. E. Oxman , M. Rocca

We study the local H\"{o}lder regularity of weak solutions to the fully fractional parabolic equations involving spatial fractional diffusion and fractional time derivatives of the Marchaud type. It is worth noting that we do not impose…

Analysis of PDEs · Mathematics 2024-06-14 Lingwei Ma , Qi Xiong , Zhenqiu Zhang

We argue that the Einstein gravity theory can be reformulated in almost Kahler (nonsymmetric) variables with effective symplectic form and compatible linear connection uniquely defined by a (pseudo) Riemannian metric. A class of…

General Relativity and Quantum Cosmology · Physics 2009-07-24 Sergiu I. Vacaru

We study the gravitational field of ultrarelativistic spinning objects (gyratons) in a modified gravity theory with higher derivatives. In particular, we focus on a special class of such theories with an infinite number of derivatives known…

General Relativity and Quantum Cosmology · Physics 2020-07-08 Jens Boos , Jose Pinedo Soto , Valeri P. Frolov

We consider some aspects of nonlocal modified gravity, where nonlocality is of the type $R \mathcal{F}(\Box) R$. In particular, using ansatz of the form $\Box R = c R^\gamma,$ we find a few $R(t)$ solutions for the spatially flat FLRW…

High Energy Physics - Theory · Physics 2017-01-10 Ivan Dimitrijevic , Branko Dragovich , Jelena Grujic , Zoran Rakic

A standard approach in the foundations of quantum mechanics studies local realism and hidden variables models exclusively in terms of violations of Bell-like inequalities. Thus quantum nonlocality is tied to the celebrated no-go theorems,…

Quantum Physics · Physics 2007-05-23 James D. Malley , Arthur Fine

We introduce the concept of nonlocal $H$-convergence. For this we employ the theory of abstract closed complexes of operators in Hilbert spaces. We show uniqueness of the nonlocal $H$-limit as well as a corresponding compactness result.…

Analysis of PDEs · Mathematics 2018-09-27 Marcus Waurick

Motivated by problems in machine learning, we study a class of variational problems characterized by nonlocal operators. These operators are characterized by power-type weights, which are singular at a portion of the boundary. We identify a…

Analysis of PDEs · Mathematics 2024-12-24 Qiang Du , James M. Scott

In this paper, we study the hyperbolic geometry of noncommutative balls generated by the joint operator radius $\omega_\rho$, $\rho\in (0,\infty]$, for $n$-tuples of bounded linear operators on a Hilbert space. In particular, $\omega_1$ is…

Functional Analysis · Mathematics 2009-12-01 Gelu Popescu

We study stress tensor correlation functions in four-dimensional conformal field theories with large $N$ and a sparse spectrum. Theories in this class are expected to have local holographic duals, so effective field theory in anti-de Sitter…

High Energy Physics - Theory · Physics 2018-01-17 Nima Afkhami-Jeddi , Thomas Hartman , Sandipan Kundu , Amirhossein Tajdini

Despite many nice properties and numerous achievements, general relativity is not a complete theory. One of actual approaches towards more complete theory of gravity is its nonlocal modification. We present here a brief review of nonlocal…

General Relativity and Quantum Cosmology · Physics 2017-01-04 Branko Dragovich

We derive general static spherically symmetric solutions in the Horava theory of gravity with nonzero shift field. These represent "hedgehog" versions of black holes with radial "hair" arising from the shift field. For the case of the…

High Energy Physics - Theory · Physics 2020-03-06 Dario Capasso , Alexios P. Polychronakos

We analyse the $\Gamma$-convergence of general non-local convolution type functionals with varying densities depending on the space variable and on the symmetrized gradient. The limit is a local free-discontinuity functional, where the bulk…

Analysis of PDEs · Mathematics 2024-11-20 Roberta Marziani , Francesco Solombrino

In this paper we will show all the linearized curvature tensors in the infinite derivative ghost and singularity free theory of gravity in the static limit. We have found that in the region of non-locality, in the ultraviolet regime (at…

General Relativity and Quantum Cosmology · Physics 2018-10-03 Luca Buoninfante , Alexey S. Koshelev , Gaetano Lambiase , Anupam Mazumdar

We review spherical and inhomogeneous analytic solutions of the field equations of Einstein and of scalar-tensor gravity, including Brans-Dicke theory, non-minimally (possibly conformally) coupled scalar fields, Horndeski, and beyond…

General Relativity and Quantum Cosmology · Physics 2021-07-28 Valerio Faraoni , Andrea Giusti , Bardia H. Fahim

The possibility of the extension of spatial diffeomorphisms to a larger family of symmetries in a class of classical field theories is studied. The generator of the additional local symmetry contains a quadratic kinetic term and a potential…

High Energy Physics - Theory · Physics 2015-05-18 Szilard Farkas , Emil J. Martinec

In this paper, the G\"{o}del-type solutions within the k-essence theory are investigated. The consistency of field equations, causality violation and existence of closed timelike curves are studied. The conditions for existence of G\"{o}del…

General Relativity and Quantum Cosmology · Physics 2019-10-18 J. G. da Silva , A. F. Santos

It is shown that polynomial gravity theories with more than four derivatives in each scalar and tensor sectors have a regular weak-field limit, without curvature singularities. This is achieved by proving that in these models the effect of…

General Relativity and Quantum Cosmology · Physics 2019-07-09 Breno L. Giacchini , Tibério de Paula Netto

It is already known that a simple nonlocal de Sitter gravity model, which we denote as $\sqrt{dS}$ gravity, contains an exact vacuum cosmological solution which mimics dark energy and dark matter and is in very good agreement with the…

General Physics · Physics 2024-04-10 Ivan Dimitrijevic , Branko Dragovich , Zoran Rakic , Jelena Stankovic