Gravitational lensing analysed by the graded refractive index of a vacuum
نویسندگان
چکیده
منابع مشابه
Studying Focusing Properties of Graded Index Photonic Crystals Made of Material with Different Refractive Index
In this paper we investigate focusing properties of graded index (GRIN) photonic crystal (PC) structures which are composed of different materials with different refractive indices. GRIN PC structure is constructed from air holes in dielectric background. The holes radii are varied in the normal direction to the propagation in such a way that a parabolic effective refractive index is produced. ...
متن کاملGravitational lensing by gravitational waves
Gravitational lensing by gravitational wave is considered. We notice that although final and initial direction of photons coincide, displacement between final and initial trajectories occurs. This displacement is calculated analytically for the plane gravitational wave pulse. Estimations for observations are discussed.
متن کاملGravitational lensing by wormholes
We have investigated the gravitational lensing by two wormholes, viz., Janis Newman-Winnicour (JNW) wormhole and Ellis wormhole. The deflection angle in the strong field limit is calculated and various lens parameters of two wormholes are compared. It is shown that the JNW wormhole exhibits the relativistic images, while the Ellis wormhole does not have any relativistic images due to the absenc...
متن کاملGravitational Lensing by Wormholes
Abstract. Natural wormholes and its astrophysical signatures have been sugested in various oportunities. By applying the strong field limit of gravitational lensing theory, we calculate the deflection angle produced by Morris-Thorne wormholes in asimptotically flat space-times. The results show that wormholes act like convergent lenses. Therefore it is hard to distinguish them from black holes ...
متن کاملAn Alternative Approach to Vacuum Energy, Dark Matter & Gravitational Lensing
Various TeVeS-like and f(R)-like theories of gravity have added an interesting twist to the search for dark matter and vacuum energy, modifying the landscape of astrophysics day by day. A common thread of various theories is a non-uniform vector field fluid in the vacuum (see an up-to-date summary of relations between various theories by Halle, Zhao & Li, arXiv0711.0958 1). These ”alternative” ...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Journal of Optics A: Pure and Applied Optics
سال: 2008
ISSN: 1464-4258,1741-3567
DOI: 10.1088/1464-4258/10/7/075001