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The universe is roughly 14 billion years old, so events at this distance are near the beginning of it.


Keeping in mind, people 200 years from now may look back on this comment and go "Ha ha, people used to think crazy things like 'the universe is only 14 billion years old'".


Science doesn't really work that way; we don't look back at Newton and think what an idiot, nor will future people think so of us. Our measurements get more accurate over time but that doesn't mean our current measurements are wrong or ever will be; they're simply as accurate as they can be now, which is pretty damn accurate. No one in the future is going to suddenly find out the universe is 100 billion years old and we had it all wrong.


Oh, the ego of us humans.

The one constant throughout the history of science is that Nature's imagination is substantially more vast than our own.

What if we discover that "old" has an entirely different meaning after light has traveled for some billions of years?

I can't think of any reasonable examples, except I remember my friend showing me a very old book about Chemistry. It had chapters about how "everything is made of a mixture of earth, water, and fire". And so on.


To your point, someone used the Hubble Effect in the other HN thread on this story to show that this observation is actually closer to 9.5 billion years old, which is significantly different than it being 12 billion years old.


> I can't think of any reasonable examples

Exactly, no one can, because your premise is wrong.

> except I remember my friend showing me a very old book about Chemistry

That was pre-science. If you can't find a modern day example there's a reason for that, the wheel of science only turns one way, forward. New science rarely if ever disproves past science, what it does is give us more accurate theories; the old theories are still correct within the framework they were made in. Einstein for example, didn't prove Newton wrong, he just had a theory that was even more accurate than Newton's.

It's not ego, it's how the process is meant to work.


For some mind-expanding examples of the (probable) insufficiency of our concept of "universe," see:

http://en.wikipedia.org/wiki/Multiverse#Tegmark.27s_classifi...

At various levels, it's possible that our own Hubble volume ("universe") is only a small stable bubble in a much larger physical system.


Well, that is true in 200 years the universe will be 14,000,000,200 years-old ;)


Really? I would have thought since we are expanding outwards, an event could be really far away simply because it is on the other side of the nexus. In other words, the universe is (28 billion) * (speed of expansion) across, rather than 14 billion


I don't follow you. The light from this event traveled 12 billion light years to get to us and current best estimates put the age of the universe at 13.75 billion years, so this light was emitted relatively close to the beginning of the universe. To reach this object now, you would indeed have to travel much farther than 12 billion light years due to the expansion of the universe.


Gah, sorry. You are correct, I was thinking about everything wrong.


The universe is (as far as we know) far larger than that. The thing is that it's literally impossible for us to interact with the parts of it outside one particular sphere.

Additionally, the universe is not expanding from one point - every point is functionally the "center" of the universe.


I do not understand how it is possible for something to expand without having a central locus. In fact, I am at a loss as to how it is possible for anything that posses bounds to fail to have a singular center. Explain?


Who says the universe has bounds? The classic analogy is of an inflating balloon. If you make two marks on the balloon, they'll expand away from each other, but neither one is the center.

Of course AFAIK there isn't any solid proof for the "finite, unbounded" idea, mostly just speculation. But it was Einstein's thing so we (laymen ;) take it pretty seriously.


You're saying that the space inside the balloon is not part of the Universe?


Well, Einstein is ;) But yeah, for the sake of the analogy we're talking about a 2-d universe which is the surface of the balloon, nothing else exists.


So objects in the Universe are not traveling because they have velocity, rather, "space itself" is expanding?


I don't think I understand your question— both are true?


From all I've read on it (the questionable balloon analogy is easily misleading at first), it's less something you can easily understand and almost something you have to trust. I guess there is another dimension involved and as such it's not all something that can be easily visualised when we're so used to dimensions as we experience them.




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