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It is shown that the addition of a non-linear term to the Lagrangian of the electromagnetic field yields a fluid with an asymptotically super-negative equation of state, causing an accelerated expansion of the universe. Some general…

Astrophysics · Physics 2009-11-10 M. Novello , S. E. Perez Bergliaffa , J. Salim

In this manuscript we deal with existence/uniqueness and regularity issues of suitable weak solutions to nonlocal problems driven by fractional Laplace type operators. Different from previous researches, in our approach we consider gradient…

Analysis of PDEs · Mathematics 2020-05-28 João Vitor da Silva , Pablo Ochoa , Analía Silva

The difficulty of explaining non-local correlations in a fixed causal structure sheds new light on the old debate on whether space and time are to be seen as fundamental. Refraining from assuming space-time as given a priori has a number of…

Quantum Physics · Physics 2018-01-15 Ämin Baumeler , Stefan Wolf

We investigate the existence of weak type solutions for a class of aggregation-diffusion PDEs with nonlinear mobility obtained as large particle limit of a suitable nonlocal version of the follow-the-leader scheme, which is interpreted as…

Analysis of PDEs · Mathematics 2018-03-30 Simone Fagioli , Emanuela Radici

The structure of classical electrodynamics based on the variational principle together with causality and space-time homogeneity is analyzed. It is proved that in this case the 4-potentials are defined uniquely. On the other hand, the…

General Physics · Physics 2007-11-20 E. Comay

Classical electrodynamics is a local theory describing local interactions between charges and electromagnetic fields and therefore one would not expect that this theory could predict nonlocal effects. But this perception implicitly assumes…

Classical Physics · Physics 2021-08-26 José A. Heras , Ricardo Heras

Superpotentials offer a direct means of calculating conserved charges associated with the asymptotic symmetries of space-time. Yet superpotentials have been plagued with inconsistencies, resulting in nonphysical or incongruent values for…

General Relativity and Quantum Cosmology · Physics 2014-02-18 Gideon I. Livshits

These are intended to be review notes on emergent symmetries, i.e., symmetries which manifest themselves in specific sectors of energy in many systems. The emphasis is on the physical aspects rather than computation methods. We include some…

High Energy Physics - Theory · Physics 2016-03-17 Pedro R. S. Gomes

We consider the electric and magnetic energy densities (or equivalently field fluctuations) in the space around a point-like field source in its ground state, after having subtracted the spatially uniform zero-point energy terms, and…

Quantum Physics · Physics 2013-05-08 Roberto Passante , Lucia Rizzuto , Salvatore Spagnolo

An acyclic causal structure can be described with directed acyclic graph (DAG), where arrows indicate the possibility of direct causation. The task of learning this structure from data is known as "causal discovery." Diverse populations or…

Machine Learning · Computer Science 2024-10-17 Bijan Mazaheri , Spencer Gordon , Yuval Rabani , Leonard Schulman

We introduce a class of non-local Lagrangians which allow for the variational derivation of non-local conser- vation laws in a self-consistent manner. The formalism developed here generalizes previous approaches, used in the context of…

Quantum Physics · Physics 2016-08-01 A. G. B. Spourdalakis , G. Pappas , P. A. Kalozoumis , F. K. Diakonos , P. Schmelcher

Lagrangian Neural Networks (LNNs) are a powerful tool for addressing physical systems, particularly those governed by conservation laws. LNNs can parametrize the Lagrangian of a system to predict trajectories with nearly conserved energy.…

Machine Learning · Computer Science 2025-07-29 Viviana Alejandra Diaz , Leandro Martin Salomone , Marcela Zuccalli

This thesis aims to study nonlocal Lagrangians with a finite and an infinite number of degrees of freedom. We obtain an extension of Noether's theorem and Noether's identities for such Lagrangians. We then set up a Hamiltonian formalism for…

High Energy Physics - Theory · Physics 2023-04-24 Carlos Heredia

Considering the effective Euler-Heisenberg Lagrangian, i.e., non-linear photon-photon interactions, we study the circular polarization of electromagnetic radiation based on the time-evolution of Stokes parameters. To the leading order, we…

High Energy Physics - Phenomenology · Physics 2012-10-03 Iman Motie , She-Sheng Xue

The causal structure of space-time offers a natural notion of an opposite or orthogonal in the logical sense, where the opposite of a set is formed by all points non time-like related with it. We show that for a general space-time the…

General Relativity and Quantum Cosmology · Physics 2022-05-04 H. Casini

We perform a systematic analysis of the conditions under which \textit{generalized} gauge field theories of compact semisimple Lie groups exhibit electrostatic spherically symmetric non-topological soliton solutions in three space…

High Energy Physics - Theory · Physics 2008-11-26 Joaquin Diaz-Alonso , Diego Rubiera-Garcia

Pathophysiolpgical modelling of brain systems from microscale to macroscale remains difficult in group comparisons partly because of the infeasibility of modelling the interactions of thousands of neurons at the scales involved. Here, to…

Neurons and Cognition · Quantitative Biology 2026-01-30 Kang You , Gary Green , Jian Zhang

In this paper we consider a claim that in the natural world there is no fact of the matter about the spatio-temporal separation of events. In order to make sense of such a notion and construct useful models of the world, it is proposed to…

Neurons and Cognition · Quantitative Biology 2024-04-18 Bartosz Jura

We present a manifestly covariant formulation of relativistic electromagnetism, focusing on the computation of electromagnetic fields from moving charges in a manifestly Lorentz-covariant manner. The electromagnetic field at a given…

Classical Physics · Physics 2025-05-28 Daiju Nakayama , Kin-ya Oda , Koichiro Yasuda

While most classical approaches to Granger causality detection assume linear dynamics, many interactions in real-world applications, like neuroscience and genomics, are inherently nonlinear. In these cases, using linear models may lead to…

Machine Learning · Statistics 2021-03-16 Alex Tank , Ian Covert , Nicholas Foti , Ali Shojaie , Emily Fox
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