- #1
Angelos K
- 48
- 0
Dear all,
so far I have only studied weak lensing. Therefore I understand little about multiple images.The light paths, by Fermat's principle, have to correspond to stationary points of the (proper) time delay. Minima, maxima saddle points. Basics are nicely reviewed here [p.14]:
http://www.ita.uni-heidelberg.de/research/bartelmann/Lectures/EinfSeminar/JeruLect.pdf
My question is why saddle points and maxima correspond to multiple images as for example claimed here [p.11]:
Takahashi et al. 2011
Am I right to assume that each maximum or saddle point creates two images?
All the best,
Angelos
so far I have only studied weak lensing. Therefore I understand little about multiple images.The light paths, by Fermat's principle, have to correspond to stationary points of the (proper) time delay. Minima, maxima saddle points. Basics are nicely reviewed here [p.14]:
http://www.ita.uni-heidelberg.de/research/bartelmann/Lectures/EinfSeminar/JeruLect.pdf
My question is why saddle points and maxima correspond to multiple images as for example claimed here [p.11]:
Takahashi et al. 2011
Am I right to assume that each maximum or saddle point creates two images?
All the best,
Angelos