| Define the terms proper distance, luminosity distance and angular diameter distance. | [1.5] |
| Show that the angular diameter distance dA and the luminosity distance dL are related by dA = dL/(1 + z)2 for an object at redshift z. | [3] |
| Does this result rely on assuming that the universe has a flat geometry? | [0.5] |
(2006 Q4.)