Expert: Ed - 1/31/2006

Question
Hi.

Can I ask a followup?

I'll have a look at the link you provided. But I wonder if there is a simple answer to the following...

I am wondering how the universe can be so big compared with its age. That would mean it must have expanded faster than the speed of light at some time doesn't it? I didn't think things were supposed to travel faster than the speed of light. Or can they sometimes?

Thanks. Steve.




















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Followup To
Question -
Hello. I have a few questions if that's ok.

1. What is the diameter of the universe or the distance across the universe?

2. I've read a little about how galaxies are grouped in galaxy clusters and those clusters in superclusters. I'd like to know if any or all of these galaxies, galaxy clusters, superclusters orbit anything.

3.Is it possible that all of the mental constructs - stars, galaxy clusters, superclusters don't really exist but are just concepts people make up? It seems the more people look the more they find and the bigger our concept of space becomes. Could all just be infinite chaos and it is our need to create sense of it that allows us to find 'evidence' to build scientific models to explain. (A bit philosophical I suppose.)
Answer -
Steve,
The universe is actually believed to be about 156 billion light years in diameter, even though it is only about 13 billion years old.

Diameter of the universe:
http://www.space.com/scienceastronomy/mystery_monday_040524.html

As for your second question, Are superclusters of galaxies revolving or orbiting around anything?  Yes, there is evidence that some superclusters revolve around a central point.  For example, our own local supercluster revolves around the Virgo Cluster.  Here is a good NASA website:
http://heasarc.gsfc.nasa.gov/docs/cosmic/local_supercluster_info.html

As for your last question... yikes.  I don't know.  I think that on some level the way we organize reality has to have meaning, but there are often ways to expand or contract the way we visualize the scale of the universe, in some way, which can make the constructs we employ seem like pure phantasm...  

Still, even if one could conceivably argue that a supernova is not "real," well, personally, I sure hope I never get caught in one!

Keep Looking Up!
--Ed

Answer
Steve,
That's an excellent point.  The answer has to do with the fact that it isn't a question of things travelling faster than the speed of light.  It's a matter of space ITSELF expanding, with new "space" being created constantly, throughout the universe.
http://www.technovelgy.com/ct/Science-Fiction-News.asp?NewsNum=149
The "Stretching Reality" section of this link says it pretty well.
http://www.space.com/scienceastronomy/mystery_monday_040524.html
Keep Looking Up!  (and thanks for the positive feedback!)
--Ed