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Continuous Limit of Multiple Lens Effect and the Optical Scalar Equation

Hiroshi Yoshida·Kouji Nakamura·Minoru Omote
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Abstract

We study the continuous limit of the multiple gravitational lensing theory based on the thin lens approximation. Under the approximation, we define a new, light-path dependent angular diameter distance $\tilde{d}$ and show that it satisfies the optical scalar equation. The distance provides relations between quantities used in the gravitational lensing theory (the convergence-, the shear- and the twist-term) and those used in the scalar optics theory (the rates of expansion, shear and rotation).

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Hiroshi Yoshida, Kouji Nakamura, Minoru Omote. 2004-07-02. Continuous Limit of Multiple Lens Effect and the Optical Scalar Equation. https://doi.org/10.1111/j.1365-2966.2005.08698.x

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