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Related papers: From global time to local physics

200 papers

We present 2 recent results on the problems of time and observables in canonical gravity. (1) We cannot use parametrized field theory to solve the problem of time because, strictly speaking, general relativity is not a parametrized field…

General Relativity and Quantum Cosmology · Physics 2007-05-23 C. G. Torre

Diffeomorphism-induced symmetry transformations and time evolution are distinct operations in generally covariant theories formulated in phase space. Time is not frozen. Diffeomorphism invariants are consequently not necessarily constants…

General Relativity and Quantum Cosmology · Physics 2009-11-11 J. M. Pons , D. C. Salisbury

Cosmic observations strongly support a time varying scenario for matter/space. On the other hand, so far, observations at solar system scale failed to identify any time variation on matter/space characteristics. To explain both results it…

Astrophysics · Physics 2007-05-23 Alfredo Gouveia Oliveira , Rodrigo de Abreu

We generalize the scale invariant gravity by allowing a negative kinetic energy term for the classical scalar field. This gives birth to a new scalar-tensor theory of gravity, in which the scalar field is in fact an auxiliary field. For a…

High Energy Physics - Theory · Physics 2007-05-23 Shih-Yuin Lin , Kin-Wang Ng

We relate physical time with the topology of magnetic field vortices. We base ourselves on a formulation of unimodular gravity where the cosmological constant $\Lambda$ appears as the canonical dual to a variable which on-shell becomes…

High Energy Physics - Theory · Physics 2024-06-24 Altay Etkin , João Magueijo , Farbod-Sayyed Rassouli

In this manuscript we initiate a systematic examination of the physical basis for the time concept in cosmology. We discuss and defend the idea that the physical basis of the time concept is necessarily related to physical processes which…

General Relativity and Quantum Cosmology · Physics 2009-02-23 Svend Erik Rugh , Henrik Zinkernagel

We investigate the gravitational waves phenomena in the geometric scalar theory of gravity (GSG) that belongs to a class of theories such that gravity is described by a single scalar field. The associated physical metric describing the…

General Relativity and Quantum Cosmology · Physics 2019-05-16 J. D. Toniato , M. Novello

We present a relational framework in which temporal structure is not fundamental but emerges from correlations within a globally stationary quantum state. Each subsystem includes an internal clock, and conditional states evolve effectively…

Quantum Physics · Physics 2025-12-19 Amir Hossein Ghasemi

We put forward the idea that in addition to diffeomorphism invariance of general relativity (GR) the gravitational interaction is invariant under arbitrary scale-deformations of the metric field. In addition, we assume that the scaling…

General Relativity and Quantum Cosmology · Physics 2022-05-19 Meir Shimon

Rather than an a priori arena in which events take place, space-time is a construction of our mind making possible a particular kind of ordering of events. As quantum entanglement is a property of states independent of classical distances,…

Quantum Physics · Physics 2015-03-26 Karl Svozil

We study the role that both vacuum fluctuations and vacuum entanglement of a scalar field play in identifying the spacetime topology, which is not prescribed from first principles---neither in general relativity or quantum gravity. We…

Quantum Physics · Physics 2016-02-10 Eduardo Martin-Martinez , Alexander R. H. Smith , Daniel R. Terno

Scalar field dynamics may give rise to a nonzero cosmological variation of fundamental constants. Within different scenarios based on the unification of gauge couplings, the various claimed observations and bounds may be combined in order…

High Energy Physics - Phenomenology · Physics 2010-04-21 Thomas Dent , Steffen Stern , Christof Wetterich

Recent progress in quantum gravity and string theory has raised interest among scientists to whether or not nature behaves discretely at the Planck scale. There are two attitudes twoards this discretenes i.e. top-down and bottom-up…

General Relativity and Quantum Cosmology · Physics 2007-05-23 S. Roy

We describe a link between the cosmological constant problem and the problem of time in quantum gravity. This arises by examining the relationship between the cosmological constant and vacuum energy in light of non-perturbative formulations…

General Relativity and Quantum Cosmology · Physics 2010-03-12 Viqar Husain

The nature of time in quantum mechanics is closely related to the use of a complex, rather than say real, Hilbert space. This becomes particularly clear when considering quantum field theory in time dependent backgrounds, such as in…

General Relativity and Quantum Cosmology · Physics 2011-11-03 G. W. Gibbons

Local time is the measure of how much time a random walk has visited a given position. In multiple scattering media, where waves are diffuse, local time measures the sensitivity of the waves to the local medium's properties. Local…

Statistical Mechanics · Physics 2013-11-28 Vincent Rossetto

Gravity theory is the basis of modern cosmological models. Thirring-Feynman's tensor field approach to gravitation is an alternative to General Relativity (GR). Though Field Gravity (FG) approach is still developing subject, it opens new…

General Relativity and Quantum Cosmology · Physics 2016-08-31 Yurij Baryshev

Basic for the definition of 'time' are clocks operating under stationary conditions. The periods of two clocks can be compared with each other via two return experiments. The central clock mediates between the rotating and the inertial…

General Physics · Physics 2013-06-25 Richard Lenk

In this paper we propose that cosmological time is a quantum observable that does not commute with other quantum operators essential for the definition of cosmological states, notably the cosmological constant. This is inspired by…

General Relativity and Quantum Cosmology · Physics 2020-02-11 Joao Magueijo , Lee Smolin

The generalisation of proper time, as an alternative to models with extra dimensions of space, has been proposed as the source of the elementary structures of matter. Direct connections with the Standard Model of particle physics together…

General Physics · Physics 2023-08-29 David J. Jackson