English
Related papers

Related papers: Modified Measures as an Effective Theory for Causa…

200 papers

The review is devoted to consideration of possible observational consequences of modified gravity theories, suggested for explanation of the contemporary accelerated expansion of the universe. The major attention is paid to F(R)-models. It…

General Relativity and Quantum Cosmology · Physics 2019-11-11 Elena Arbuzova

This is a set of introductory lecture notes on conformal field theory. Unlike most existing reviews on the subject, CFT is presented here from the perspective of a unitary quantum field theory in Minkowski space-time. It begins with a…

High Energy Physics - Theory · Physics 2023-05-04 Marc Gillioz

Causal fermion systems incorporate local gauge symmetry in the sense that the Lagrangian and all inherent structures are invariant under local phase transformations of the physical wave functions. In the present paper it is explained and…

Mathematical Physics · Physics 2020-08-10 Felix Finster , Sebastian Kindermann

Modified gravity (MOG) is a covariant, relativistic, alternative gravitational theory whose field equations are derived from an action that supplements the spacetime metric tensor with vector and scalar fields. Both gravitational (spin 2)…

General Relativity and Quantum Cosmology · Physics 2018-03-14 M. A. Green , J. W. Moffat , V. T. Toth

In this study, we present a modified quantum theory, denoted as $QT^\ast$, which introduces mass-dependent decoherence effects. These effects are derived by averaging the influence of a proposed global quantum fluctuation in position and…

Quantum Physics · Physics 2024-12-18 Heinz-Jürgen Schmidt

We study the late time cosmological evolution of $f(R)$ theories of modified gravity, with the matter content of the universe being that of collisional self interacting matter. We assume that the universe is described by a flat…

General Relativity and Quantum Cosmology · Physics 2015-06-22 V. K. Oikonomou , N. Karagiannakis

We reconsider quantum gravitational threshold effects to the unification of fermion masses in Grand Unified Theories. We show that the running of the Planck mass can have a sizable effect on these thresholds which are thus much more…

High Energy Physics - Phenomenology · Physics 2011-09-13 Xavier Calmet , Ting-Cheng Yang

Quantum Measure Theory (QMT) is an approach to quantum mechanics, based on the path integral, in which quantum theory is conceived of as a generalised stochastic process. One of the postulates of QMT is that events with zero quantum measure…

Quantum Physics · Physics 2017-10-20 Fay Dowker , Vojtěch Havlíček , Cyprian Lewandowski , Henry Wilkes

We explore the weak-field phenomenology of a compact star spacetime modified by quantum gravitational corrections derived from the effective field theoretical (EFT) approach by Calmet et al. [1]. These corrections, encoded in non-local…

General Relativity and Quantum Cosmology · Physics 2026-02-10 Reggie C. Pantig , Ali Ovgun , Gaetano Lambiase

We study scalar cosmological perturbations in $f(R, T)$ modified gravity theories being $T$ the trace of the energy-momentum tensor. We provide detailed equations for the matter energy density contrast. We solve then numerically to promote…

General Relativity and Quantum Cosmology · Physics 2024-08-28 Jonas Pinheiro da Silva , Hermano Velten

New corrections to General Relativity are considered in the context of modified $f(R)$ gravity, that satisfy cosmological and local gravity constraints. The proposed models behave asymptotically as $R-2\Lambda$ at large curvature and show…

General Relativity and Quantum Cosmology · Physics 2022-01-13 L. N. Granda

General Relativity (GR) is consistent with a wide range of experiments/observations from millimeter scales up to galactic scales and beyond. However, there are reasons to believe that GR may need to be modified because it includes…

General Relativity and Quantum Cosmology · Physics 2019-07-17 Leandros Perivolaropoulos , Lavrentios Kazantzidis

This work is the extension of author`s research, where the modified theory of induced gravity (MTIG) is proposed. The theory describes two systems (stages): Einstein (ES) and "restructuring" (RS). We consider equations with quadratic…

General Physics · Physics 2019-11-22 Farkhat Zaripov

Requiring causality on measurements in quantum field theory seems to impose strong conditions on a self-adjoint operator to be really measurable. This may seem limiting and artificial in the operator language of algebraic quantum field…

History and Philosophy of Physics · Physics 2021-09-08 Jonáš Fuksa

In the pursuit of a general formulation for a modified gravitational theory at the non-relativistic level and as an alternative to the dark matter hypothesis, we construct a model valid over a wide variety of astrophysical scales. Through…

Astrophysics of Galaxies · Physics 2011-12-13 S. Mendoza , X. Hernandez , J. C. Hidalgo , T. Bernal

We use the cosmic shear data from the Canada-France-Hawaii Telescope Lensing Survey to place constraints on $f(R)$ and {\it Generalized Dilaton} models of modified gravity. This is highly complimentary to other probes since the constraints…

Cosmology and Nongalactic Astrophysics · Physics 2015-10-21 Joachim Harnois-Déraps , Dipak Munshi , Patrick Valageas , Ludovic van Waerbeke , Philippe Brax , Peter Coles , Luca Rizzo

The purpose of this paper is to challenge the existing paradigm on which contemporary models of generalised uncertainty relations (GURs) are based, that is, the assumption of modified commutation relations. We review an array of theoretical…

General Relativity and Quantum Cosmology · Physics 2023-02-17 Matthew J. Lake , A. Watcharapasorn

In seeking to arrive at a theory of ``quantum gravity'', one faces several choices among alternative approaches. I list some of these ``forks in the road'' and offer reasons for taking one alternative over the other. In particular, I…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Rafael D. Sorkin

The synthetic control method (SCM) is a widely used tool for evaluating causal effects of policy changes in panel data settings. Recent studies have extended its framework to accommodate complex outcomes that take values in metric spaces,…

Methodology · Statistics 2026-01-13 Ryo Okano , Daisuke Kurisu

We consider Lorentzian manifolds as examples of partially ordered measure spaces, sets endowed with compatible partial order relations and measures, in this case given by the causal structure and the volume element defined by each…

General Relativity and Quantum Cosmology · Physics 2013-11-20 Luca Bombelli , Johan Noldus , Julio Tafoya