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AirBrush, So far I like your answer (to Swaha) the best. Regards, TAR

Klaynos, So still, I have a few questions. One is, when I read a finding, like "the universe is 158 billion light years wide", is that statement assuming a universal "now", and imagining the universe when all objects and locations in space are 13.7 billion years old? Regards, TAR

Klaynos, I am just trying to get a good picture of what did and is happening in the universe (generally speaking.) We will not see what is happening "now" anywhere in the universe until the light of the events get to us. We will have to wait 4.3 years to see what is happening "now" on Alpha Centauri. (But we can see now, exactly what was going on on Alpha Centauri 4.3 years ago.) We can only surmise that the rest of the universe is most likely pretty much like it seems to be around here, with strings of galaxies, clusters of galaxies, and voids. The objects we see 13 billion light years away, most likely tell us what things around here were like those billions of years ago. Those objects are no longer what occupies that location in space, that population III star, or whatever we see(in infrared) has long since become whatever population III stars became, and that location of space is probably inhabited by the children objects, or grandchildren objects of that population III star. "Now" meaning what that location of space is like, 13.7 billion years after the Big Bang. I have wondered several times, in my readings in the last couple days, what people mean, time wise, when they say "the universe consists...". Are they talking about what is around here and figuring that is what the rest of the universe consists of as well, or are they making their measurements and calculations based on what they observe far away (and hence long ago.) If it is the latter, then they should be saying what the universe consisted of. Regards, TAR

Klaynos, Thanks for the response. I think I have not, before, but do now, understand the role of expansion in imagining what is and has gone on in the universe. It has to be happening at a really rapid pace, though, to explain everything. Let me do some reading on expansion. Regards, TAR Merged post follows: Consecutive posts mergedDid a little reading. At 13km/s/Mpc, I suppose those far away objects that we are finding are receeding at what my rudimentary math, would put at about 1/2 the speed of light. But what sticks in my craw still is the fact that long ago, those objects were much closer to our location in space. Logic would suggest that object a can not be seen by object c because the expanse of space, now, is wider than light can travel in the time it has had to travel anywhere since the beginning of the universe. But, if we are talking about the objects a and c, that we are measuring, now, 13 billion years after the start of the universe, at 10 billion light years distance from us respectively, we are really talking about the image of a and c, when they were 3 billion years old. Now, if it took the light from 3 billion year old c, 10 billion years to arrive at our (b) location, it is going to take more that 10 million years more, to cover the distance from b to a across an already daunting and expanding distance. So I have no problem accepting that the light from 3 billion year old c, will never reach a's location in expanding space. However, this does not suggest that the light from location a never has, and never will, reach location c. The light from a 1 billion year old "location a" left "location a" when a-b-c where much closer together, and has had 12 billion years to make the trek to location c. Although I have not done the calculus, my intuition suggests that the light from 1 billion year old location a has already had the time to reach location c. How old location c was, is or will be, when the light from 1 billion year old location a reaches it, even if it is in the form of "background radiation", rather than an identifiable object, is not as important as DOES it. If it does, then I would guess that every location in space has a view of every other location in space, even if the view is of the location at a very very young age. Regards, TAR

Just can't make sense of it. If we can look in one direction, and see an object 10 billion light years away, and look in the opposite direction and see an object 10 billion light years away, that would suggest a universe that was at the very least, 20 billion light years wide, 10 billion years ago. The universe has continued to expand in the mean time, and those two objects are even more distant from each other now. Merged post follows: Consecutive posts mergedNeglected to type the implied question. If the universe is 15 billion years old, the two objects only had 5 billion years to get separated by 20 billion lightyear's distance, which means they were separated at a rate much greater than the speed of light. (twice the speed?). Isn't this impossible? And if we would discover an object 11billion lightyears away, and look in the opposite direction with the same technology and discover a similar object 11billion light years away, that would put those two objects, each at an age of 4 billion years, with a separation of 22 billion lightyears. Hypothetical 12 billion lightyear distant objects, 3 billion years old separated by 24 billion lightyears, 2billion year olds by 26 billion lightyears, 1byearolds by 28bly, and so on, till we find the earliest things we can see, at the GREATEST distance of separation. Doesn't this imply that the universe was BIGGER when it was younger? Where am I going wrong?