80 citations · 148 across the 5 of their papers we have counts for
5 papers
Gravitational lens on a static optical constant-curvature background: Its application to Weyl gravity model
Keita Takizawa, Hideki Asada
This paper extends the de-Sitter/anti-de Sitter (dS/AdS) background method based on the optical metric for gravitational lens [Phys. Rev. D 105, 084022 (2022)] to a static optical…
Gravitational lens on de-Sitter background
Keita Takizawa, Hideki Asada
Gravitational lenses are examined in de-Sitter (dS) background, for which the existence of the dS horizon is taken into account and hyperbolic trigonometry is used together with th…
Iterative solutions for the gravitational lens equation in the strong deflection limit
Keita Takizawa, Hideki Asada
Two exact lens equations have been recently shown to be equivalent to each other, being consistent with the gravitational deflection angle of light from a source to an observer, bo…
Gravitational lens without asymptotic flatness: Its application to the Weyl gravity
Keita Takizawa, Toshiaki Ono, Hideki Asada
We discuss, without assuming asymptotic flatness, a gravitational lens for an observer and source that are within a finite distance from a lens object. The proposed lens equation i…
Gravitational deflection angle of light: Definition by an observer and its application to an asymptotically nonflat spacetime
Keita Takizawa, Toshiaki Ono, Hideki Asada
The gravitational deflection angle of light for an observer and source at finite distance from a lens object has been studied by Ishihara et al. [Phys. Rev. D, 94, 084015 (2016)],…