Naked Science Forum

Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: Joe L. Ogan on 08/02/2010 00:20:21

Title: What is Einstein's Cross?
Post by: Joe L. Ogan on 08/02/2010 00:20:21

What is Einstein's Cross?  Does it have any significance in the scientific world.  Please explain.  Thanks for comments.  Joe L. Ogan

Title: What is Einstein's Cross?
Post by: JP on 08/02/2010 05:24:24

Real lenses (the kind you'd find in glasses or cameras) work by bending light.  Einstein's general relativity predicts that gravity can also bend light, so that if you have a large mass between you and some object, the light can get bent around it.  Einstein's cross is an example of this bending, where four images of a quasar show up because of the way a distant galaxy is bending the quasar's light.