Classical tests for Weyl gravity: Deflection of light and time delay

The theory of the dynamic medium of reference has already been presented in several articles [Pignard, Phys. Essays 32, 422 (2019); 33, 395 (2020); 34, 61 (2021); 34, 279 (2021)], and in particular in Pignard, Phys. Essays 32, 422 (2019). The article [Pignard, Phys. Essays 34, 279 (2021)] gives an explanation and mathematical developments of the gravitational acceleration from atomic nuclei of a massive body. General relativity considers a massive body, like the Earth or the Sun, globally, macroscopically, simply as an object of mass M (which curves space‐time). However, when one goes into details, this mass M is made up of atoms which are themselves mainly made up of nuclei of nucleons (if we neglect the mass of electrons in comparison of that of the nucleus). Thus, it is mainly the nuclei of a massive body that create the force of gravity! The dynamic medium of reference theory determines the gravitational acceleration microscopically by taking into account all the atomic nuclei that make up a massive body [Pignard, Phys. Essays 32, 422 (2019)]. This creates a strong link between gravity and the nuclear domain. This article goes further with the description of a model of the atomic nucleus. This makes it possible to establish that the strong force or nuclear force, which ensures the cohesion of the nucleus, is due to the strong acceleration of the flux of the medium which is a vector average of the flux of gravitons. This gives an expression of the nuclear force similar to the force of gravity but with a constant K ≈ 1031 m s−2, much higher than the gravitational constant G. This article shows that the functioning, the mechanism of the nucleus, makes it possible to explain the nuclear force and also to find the gravitational acceleration. From there, it is deduced that the photons are deflected by the strong acceleration due to an atom nucleus. They are also slowed down by an atom nucleus which creates a delay in their travel time which we call the nuclear time delay of light. Finally, an experiment is proposed to verify the phenomenon of nuclear deflection of light and the nuclear time delay of light.

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Constraints on scalar–tensor theory of gravity by solar system tests

The European Physical Journal C ◽

10.1140/epjc/s10052-020-08536-0 ◽

2020 ◽

Vol 80 (10) ◽

Author(s):

P. A. González ◽

Marco Olivares ◽

Eleftherios Papantonopoulos ◽

Yerko Vásquez

Keyword(s):

Time Delay ◽

Scalar Field ◽

Solar System ◽

Gravitational Redshift ◽

Scalar Tensor Theory ◽

Einstein Tensor ◽

Perihelion Precession ◽

Deflection Of Light ◽

Tensor Theory ◽

Theory Of Gravity

AbstractWe study the motion of particles in the background of a scalar–tensor theory of gravity in which the scalar field is kinetically coupled to the Einstein tensor. We constrain the value of the derivative parameter z through solar system tests. By considering the perihelion precession we obtain the constraint $$\sqrt{z}/m_{\mathrm{p}} > 2.6\times 10^{12}$$ z / m p > 2.6 × 10 12 m, the gravitational redshift $$\frac{\sqrt{z}}{m_{\mathrm{p}}}>2.7\times 10^{\,10}$$ z m p > 2.7 × 10 10 m, the deflection of light $$\sqrt{z}/m_{\mathrm{p}} > 1.6 \times 10^{11}$$ z / m p > 1.6 × 10 11 m, and the gravitational time delay $$\sqrt{z}/m_{\mathrm{p}} > 7.9 \times 10^{12}$$ z / m p > 7.9 × 10 12 m; thereby, our results show that it is possible to constrain the value of the z parameter in agreement with the observational tests that have been considered.

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Deflection of light to second order in conformal Weyl gravity

Journal of Cosmology and Astroparticle Physics ◽

10.1088/1475-7516/2013/04/048 ◽

2013 ◽

Vol 2013 (04) ◽

pp. 048-048 ◽

Cited By ~ 5

Author(s):

Joseph Sultana

Keyword(s):

Second Order ◽

Deflection Of Light ◽

Weyl Gravity

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Probing the parameters of a Schwarzschild black hole surrounded by quintessence and cloud of strings through four standard astrophysical tests

The European Physical Journal C ◽

10.1140/epjc/s10052-021-09654-z ◽

2021 ◽

Vol 81 (10) ◽

Author(s):

Víctor H. Cárdenas ◽

Mohsen Fathi ◽

Marco Olivares ◽

J. R. Villanueva

Keyword(s):

Black Hole ◽

Time Delay ◽

Observational Data ◽

Gravitational Redshift ◽

Schwarzschild Black Hole ◽

Gravitational Perturbations ◽

Deflection Of Light ◽

Static Black Hole ◽

Planetary Orbits ◽

General Relativistic

AbstractIn this paper, we concern about applying general relativistic tests on the spacetime produced by a static black hole associated with cloud of strings, in a universe filled with quintessence. The four tests we apply are precession of the perihelion in the planetary orbits, gravitational redshift, deflection of light, and the Shapiro time delay. Through this process, we constrain the spacetime’s parameters in the context of the observational data, which results in about $$\sim 10^{-9}$$ ∼ 10 - 9 for the cloud of strings parameter, and $$\sim 10^{-20}$$ ∼ 10 - 20 m$$^{-1}$$ - 1 for that of quintessence. The response of the black hole to the gravitational perturbations is also discussed.

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Solar system tests in Rastall gravity

Modern Physics Letters A ◽

10.1142/s0217732320500340 ◽

2019 ◽

Vol 35 (07) ◽

pp. 2050034 ◽

Cited By ~ 4

Author(s):

Tuhina Manna ◽

Farook Rahaman ◽

Monimala Mondal

Keyword(s):

General Relativity ◽

Black Hole ◽

Time Delay ◽

Solar System ◽

Astrophysical Object ◽

Tests Of General Relativity ◽

Deflection Of Light

In this paper, we have investigated the classical tests of General Relativity like precession of perihelion, deflection of light and time delay by considering a phenomenological astrophysical object like Sun, as a neutral regular Hayward black hole in Rastall gravity. We have tabulated all our results for some appropriate values of the parameter [Formula: see text]. We have compared our values with [Formula: see text], which corresponds to the Schwarzschild case. Also the value of [Formula: see text] is of particular interest as it gives some promising results.

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