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Related papers: Equivalence Principle in Chameleon Models

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We analyze a quantum version of the weak equivalence principle, in which we compare the response of a static particle detector crossed by an accelerated cavity with the response of an accelerated detector crossing a static cavity in…

Quantum Physics · Physics 2018-10-16 Erickson Tjoa , Robert B. Mann , Eduardo Martin-Martinez

A quantum correction to the Brans-Dicke theory due to interactions among matter fields is calculated, resulting in violation of WEP, hence giving a constraint on the parameter $\omega$ far more stringent than accepted so far. The tentative…

General Relativity and Quantum Cosmology · Physics 2015-06-25 Yasunori Fujii

We present phase shift measurements for neutron matter waves in vacuum and in low pressure Helium using a method originally developed for neutron scattering length measurements in neutron interferometry. We search for phase shifts…

High Energy Physics - Phenomenology · Physics 2015-06-23 H. Lemmel , Ph. Brax , A. N. Ivanov , T. Jenke , G. Pignol , M. Pitschmann , T. Potocar , M. Wellenzohn , M. Zawisky , H. Abele

Cosmological probes pose an inverse problem where the measurement result is obtained through observations, and the objective is to infer values of model parameters which characterize the underlying physical system -- our Universe. Modern…

Instrumentation and Methods for Astrophysics · Physics 2019-05-21 Timur Takhtaganov , Zarija Lukic , Juliane Mueller , Dmitriy Morozov

We describe space--time fluctuations by means of small fluctuations of the metric on a given background metric. From a minimally coupled Klein--Gordon equation we obtain within a weak-field approximation up to second order and an averaging…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Ertan Göklü , Claus Lämmerzahl

Apart from the suspected violation of the CPT invariance, we might expect if the measurements of antihydrogen atoms provide testing Weak Equivalence Principle (WEP) in the gravitational phenomena. We start with how its violation can be…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Yasunori Fujii

Field emission studies incorporating the effect of space charge reveal that for planar emitters, the steady-state field $E_P$, after initial transients, settles down to a value lower than the vacuum field $E_L$. The ratio $\vartheta =…

Accelerator Physics · Physics 2022-03-29 Debabrata Biswas , Raghwendra Kumar , Gaurav Singh

Accurate analysis of precision ranges to the Moon has provided several tests of gravitational theory including the Equivalence Principle, geodetic precession, parameterized post-Newtonian (PPN) parameters $\gamma$ and $\beta$, and the…

General Relativity and Quantum Cosmology · Physics 2008-11-26 James G. Williams , Slava G. Turyshev , Thomas W. Murphy

We investigate a link between the running of the fine structure constant $\alpha$ and a time evolving scalar dark energy field. Employing a versatile parameterization for the equation of state, we exhaustively cover the space of dark energy…

Astrophysics · Physics 2009-11-10 Michael Doran

We carry out a suite of cosmological simulations of modified action f(R) models where cosmic acceleration arises from an alteration of gravity instead of dark energy. These models introduce an extra scalar degree of freedom which enhances…

Astrophysics · Physics 2008-12-30 Hiroaki Oyaizu , Marcos Lima , Wayne Hu

Wide classes of new fundamental physics theories cause apparent variations in particle mass ratios in space and time. In theories that violate the weak equivalence principle (EP), those variations are not uniform across all particles and…

We consider an environmentally dependent violation of Lorentz invariance in scalar-tensor models of modified gravity where General Relativity is retrieved locally thanks to a screening mechanism. We find that fermions have a modified…

High Energy Physics - Phenomenology · Physics 2015-06-04 Philippe Brax

Dynamical scalar fields in an effective four-dimensional field theory are naturally expected to couple to the rest of the theory's degrees of freedom, unless some new symmetry is postulated to suppress these couplings. In particular, a…

The asymptotic equivalence of canonical and microcanonical ensembles is a central concept in statistical physics, with important consequences for both theoretical research and practical applications. However, this property breaks down under…

Statistical Mechanics · Physics 2023-05-30 Qi Zhang , Diego Garlaschelli

The ultra-precise Gravity Probe B experiment measured the frame-dragging effect and geodetic precession on four quartz gyros. We use this result to test WEP II (Weak Equivalence Principle II) which includes rotation in the universal…

General Relativity and Quantum Cosmology · Physics 2011-08-22 Wei-Tou Ni

Complex phenomena in engineering and the sciences are often modeled with computationally intensive feed-forward simulations for which a tractable analytic likelihood does not exist. In these cases, it is sometimes necessary to estimate an…

Methodology · Statistics 2020-06-18 Niccolò Dalmasso , Ann B. Lee , Rafael Izbicki , Taylor Pospisil , Ilmun Kim , Chieh-An Lin

Recently it was argued that the conformal coupling of the chameleon to matter fields created an issue for early universe cosmology. As standard model degrees of freedom become non-relativistic in the early universe the chameleon is…

High Energy Physics - Theory · Physics 2016-05-17 Antonio Padilla , Emma Platts , David Stefanyszyn , Anthony Walters , Amanda Weltman , Toby Wilson

Recently we drew attention to the fact that most recent 5th force searches and tests of the weak equivalence principle (WEP) utilize only one or two pairs of test samples. We argue that, despite the great precision of these experiments, the…

High Energy Physics - Phenomenology · Physics 2021-05-10 Ephraim Fischbach , Dennis E. Krause , Megan H. McDuffie , Michael J. Mueterthies

The striking success of the Standard Model in explaining precision data and, at the same time, its lack of explanations for various fundamental phenomena, such as dark matter or the baryon asymmetry of the universe, suggests new physics at…

High Energy Physics - Phenomenology · Physics 2025-04-23 Gino Isidori , Felix Wilsch , Daniel Wyler

Perfectly conducting boundaries, and their Dirichlet counterparts for quantum scalar fields, predict nonintegrable energy densities. A more realistic model with a finite ultraviolet cutoff yields two inconsistent values for the force on a…

High Energy Physics - Theory · Physics 2016-05-18 S. W. Murray , C. M. Whisler , S. A. Fulling , Jef Wagner , H. B. Carter , David Lujan , F. D. Mera , T. E. Settlemyre