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I've juggled these questions around my mind for a few days now and so far haven't been able to google any useful information:

1. What is the approximate 3D shape of the observable universe? The Wikipedia article on this subject talks about weird stuff, like a "flat universe" and lists other highly mathematical rabble, while presumably presenting the topology of the universe as a whole, not just the observable part of it. Do we even have means to give a simple answer, and if not, what is preventing this?

2. What is the ratio of observable blue-shifted objects to red-shifted ones? Is there an upper limit to the possible blue shift an observed object can have (in the lay sense that an object is approaching us at a maximum possible speed of X km/s), and can we draw any conclusions as to the "speed" at which space itself is expanding? My uneducated mind tells me that the faster stuff scurries away from us in all directions, the fewer blue-shifted objects we should be able to observe, hence deriving a "boundary" of sorts where objects appear to stand still, and beyond which space itself is expanding so fast that no blue-shift could possibly be detected.

There were some other questions lying around in my pumpkin, but they elude me as of now. I might cough them up later, when I've had a beer or two (works wonders sometimes). Thanks for any answers!

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# Newbish questions (shape of the observable universe, blueshift, etc.)

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