All Questions
3
questions
10
votes
1
answer
378
views
What is the scale of things you can see with gravitational lensing?
I'm trying to understand the examples of gravity lensing (using the general relativity property of large masses to bend light like a lens).
Most of the examples I see are of some galaxy (presumably ...
9
votes
1
answer
251
views
How to find the distance between two quasars
I want to calculate the distance between two quasars of which I know the angular position and the red shift. Let $Q_1=(\alpha_1,\delta_1, z_1)$ and $Q_2=(\alpha 2,\delta 2, z_2)$ and suppose $z_2 > ...
2
votes
1
answer
120
views
Has the Lyman-alpha forest ever been used to test Arp's theory?
Has the Lyman-alpha forest ever been used to test Halton Arp's theory that quasars are not cosmological but instead are ejected from relatively near-by galaxies? If Arp was right, then the spectra of ...