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mercury
2005-Apr-14, 10:25 AM
If the quasars are showing such a large red shift, they should be travelling away practically as long as the age of the universe. Then, how did they take birth, create fusion(live the life of star), die to become neutron stars, etc. That must have happened in a very short time. Is there any other explanation for this red shift? Also, quasars have 2 inner cores which seem to travel at superluminal velocities. That is definitely impossible, right? Then why do we observe this phenomenon?

John L
2005-Apr-14, 02:24 PM
One widely accepted explanation of Quasars is that they are the highly active black holes at the center of very young galaxies that are consuming large amounts of matter. As that matter falls toward the event horizon it gives off highly energetic photons that we see as the quasar.

As for stars living and dieing fast, the largest stars we know live for only a few million years before consuming their nuclear fuel and destroying themselves. It is stars as small as our sun that can last 10 billion years, and it is beleived that red dwarf stars may last for 100 billion years before running out of fuel.

And superluminal velocities are not possible, but superluminal expansion is. The expansion of the universe is cumulative so the further away an object is the faster the intervening space is expanding. At a great enough distance the cumulative expansion of space will be greater than the speed of light.

Matthew
2005-Apr-15, 01:45 AM
Originally posted by mercury@Apr 14 2005, 09:25 PM
Also, quasars have 2 inner cores which seem to travel at superluminal velocities.
2 inner cores? I always thought that quasars were huge black holes, which would have only one center.