Astronomers have discovered a rare Einstein ring in the distant universe. The ring is formed when light from a galaxy is bent by the gravity of another galaxy in front of it. The phenomenon reveals new insights into dark matter and cosmic expansion.

#EinsteinRing #DarkMatter #Cosmology

https://phys.org/news/2023-04-einstein-distant-galaxies-closer-dark.html

@tomassetti Helbig uses an #EinsteinRing to find the transverse velocity of the #GravitationalLens, but the ring is the image of the entire high-z object. One cannot obtain an accurate redshift for a part of the ring.

Multiple-images are better as in the paper by Wang et al.
🔗 https://doi.org/10.3847/1538-4357/ac98aa
(cited by Helbig) which gives a better description of the #RedshiftDrift measurement.

@GravityGrinch any comment on the simple gravitational lens models used in these papers? Can this work?