The Experts below are selected from a list of 318 Experts worldwide ranked by ideXlab platform
P. Vanhove - One of the best experts on this subject based on the ideXlab platform.
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Bending of Light in quantum gravity
Physical Review Letters, 2015Co-Authors: N E J Bjerrumbohr, J.f. Donoghue, B-r. Holstein, Ludovic Planté, P. VanhoveAbstract:Theorists calculate how quantum gravity effects could alter the Bending of Light induced by massive objects.
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Bending of Light in Quantum Gravity
2014Co-Authors: N. Bjerrum-bohr, J.f. Donoghue, B-r. Holstein, Ludovic Planté, P. VanhoveAbstract:We consider the scattering of Light-like matter in the presence of a heavy scalar object (such as the sun or a black hole). By treating general relativity as an effective field theory we directly compute the non-analytic parts of the one-loop gravitational amplitude for the scattering of massless scalars or photons from an external massive scalar field. These results allow a semi-classical computation of the Bending angle for Light-rays grazing the sun, including long-range ħ contributions. We discuss implications of this computation, in particular the violation of some classical formulations of the equivalence principle.
Jin Young Kim - One of the best experts on this subject based on the ideXlab platform.
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Bending of electromagnetic wave in an ultra strong magnetic field
Journal of Cosmology and Astroparticle Physics, 2012Co-Authors: Jin Young KimAbstract:We consider the Bending of Light by nonlinear electrodynamics when the magnetic field B exceeds the critical value Bc = m2c2/e = 4.4 × 109T. Using the index of refraction derived from the analytic series representation in one-loop effective action of QED, we found the trajectory and the Bending angle of Light in geometric optics. The angle bent by ultra-strong magnetic field of magnetar was estimated and compared with the gravitational Bending. The result may be useful in studying the lensing, birefringence, and other nonlinear quantum electrodynamic effects above Bc.
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Bending of electromagnetic wave in an ultra strong magnetic field
arXiv: High Energy Physics - Phenomenology, 2012Co-Authors: Jin Young KimAbstract:We consider the Bending of Light by nonlinear electrodynamics when the magnetic field $B$ exceeds the critical value $B_{\rm c}$. Using the index of refraction derived from the analytic series representation in one-loop effective action of QED, we found the trajectory and the Bending angle of Light in geometric optics. The angle bent by ultra-strong magnetic field of magnetar was estimated and compared with the gravitational Bending. The result may be useful in studying the lensing, birefringence, and other nonlinear quantum electrodynamic effects above $B_{\rm c}$.
Thomas Müller - One of the best experts on this subject based on the ideXlab platform.
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Analytic observation of a star orbiting a Schwarzschild black hole
General Relativity and Gravitation, 2008Co-Authors: Thomas MüllerAbstract:A star orbiting a Schwarzschild black hole can be used as a toy model for an educational study of the relativistic effects like Bending of Light, geodesic precession, and frequency shift. Additionally, the finiteness of the speed of Light plays a crucial role for the visual appearance of the star. We will develop an analytic method to show the difference between the actual and the apparent position of the star depending on the observation time and the observer’s inclination to the orbital plane.
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Einstein rings as a tool for estimating distances and the mass of a Schwarzschild black hole
Physical Review D, 2008Co-Authors: Thomas MüllerAbstract:The Bending of Light due to the curvature of spacetime close to a black hole is so strong that Light can ' even return to the point of emittance yielding an Einstein ring. Using the analytic solution of the geodesic equation in Schwarzschild spacetime and a distant star or a flash of Light, we will be able to determine the mass of a black hole as well as the distance of the observer to this black hole, at least in principle.
D P Marrone - One of the best experts on this subject based on the ideXlab platform.
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the shape of the black hole photon ring a precise test of strong field general relativity
Physical Review D, 2020Co-Authors: Samuel E Gralla, Alexandru Lupsasca, D P MarroneAbstract:We propose a new test of strong-field general relativity (GR) based on the universal interferometric signature of the black hole photon ring. The photon ring is a narrow ring-shaped feature, predicted by GR but not yet observed, that appears on images of sources near a black hole. It is caused by extreme Bending of Light within a few Schwarzschild radii of the event horizon and provides a direct probe of the unstable bound photon orbits of the Kerr geometry. We show that the precise shape of the observable photon ring is remarkably insensitive to the astronomical source profile and can therefore be used as a stringent test of GR. We forecast that a tailored space-based interferometry experiment targeting M87* could test the Kerr nature of the source to the sub-sub-percent level.
Demosthenes Kazanas - One of the best experts on this subject based on the ideXlab platform.
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Bending of Light in modified gravity at large distances
Physical Review D, 2012Co-Authors: Joseph Sultana, Demosthenes KazanasAbstract:We discuss the Bending of Light in a recent model for gravity at large distances containing a Rindler-type acceleration proposed by Grumiller [Phys. Rev. Lett. 105, 211303 (2010)]. We consider the static, spherically symmetric metric with cosmological constant $\ensuremath{\Lambda}$ and Rindler-like term $2ar$ presented in this model, and we use the procedure by Rindler and Ishak [W. Rindler and M. Ishak, Phys. Rev. D 76, 043006 (2007).] to obtain the Bending angle of Light in this metric. Earlier work on Light Bending in this model by Carloni, Grumiller, and Preis [Phys. Rev. D 83, 124024 (2011)], using the method normally employed for asymptotically flat space-times, led to a conflicting result (caused by the Rindler-like term in the metric) of a Bending angle that increases with the distance of closest approach ${r}_{0}$ of the Light ray from the centrally concentrated spherically symmetric matter distribution. However, when using the alternative approach for Light Bending in nonasymptotically flat space-times, we show that the linear Rindler-like term produces a small correction to the general relativistic result that is inversely proportional to ${r}_{0}$. This will in turn affect the bounds on Rindler acceleration obtained earlier from Light Bending and casts doubts on the nature of the linear term $2ar$ in the metric.
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Bending of Light in conformal weyl gravity
Physical Review D, 2010Co-Authors: Joseph Sultana, Demosthenes KazanasAbstract:We reexamine the Bending of Light issue associated with the metric of the static, spherically symmetric solution of Weyl gravity discovered by Mannheim and Kazanas (1989). To this end we employ the procedure used recently by Rindler and Ishak to obtain the Bending angle of Light by a centrally concentrated spherically symmetric matter distribution in a Schwarzschild-de Sitter background. In earlier studies the term {gamma}r in the metric led to the paradoxical result of a Bending angle proportional to the photon impact parameter, when using the usual formalism appropriate to asymptotically flat space-times. However, employing the approach of Light Bending of Rindler and Ishak we show that the effects of this term are in fact insignificant, with the discrepancy between the two procedures attributed to the definition of the Bending angle between the asymptotically flat and nonflat spaces.