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Why is there a normal galaxy sitting at the edge of the Universe?

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Re: Why is there a normal galaxy sitting at the edge of the Universe?

#32
post #22

Earlier quoted context omitted.

No, 13 billion years is the age of the universe. The observable universe is a sphere with a diameter of ~93 billion light years (And is likely to only be a subset of the entire universe).

How can we observe things over 40 billion light years away if they've only been around to emit light for 13 billion years?

The universe has been expanding ever since the Big Bang. Things that are very far away are moving away from us at speeds "faster" than light. No, they're not violating the cosmic speed limit. The fabric of spacetime itself is expanding everywhere, and that makes objects at very large distances apart get even further apart faster than a lightspeed traveler could move them.

https://www.space.com/33306-how-does-the-universe-expand-fas...

Re: Why is there a normal galaxy sitting at the edge of the Universe?

#33
post #22

I've always been puzzled by the estimated age of the universe at being 13 billion years. That's just the size of the observable universe, correct? Isn't there a future horizon beyond which light will not currently reach us?

No, 13 billion years is the age of the universe. The observable universe is a sphere with a diameter of ~93 billion light years (And is likely to only be a subset of the entire universe).

Sorry to bikeshed, but I was struck by the word "likely" in your parenthetical. Are there models of the universe that predict our observable universe is _not_ a subset of the entire universe? How would one describe cosmological expansion in such a model?

Re: Why is there a normal galaxy sitting at the edge of the Universe?

#34

> Why is there a normal galaxy sitting at the edge of the universe? To facilitate the restaurant?

This is a reference to Douglas Adams' absurdist Sci Fi series, "Hitchhiker's Guide to the Galaxy," which is amazing and I recommend everyone read!

https://www.goodreads.com/book/show/13.The_Ultimate_Hitchhik...

(The first book is "Hitchhiker's Guide to the Galaxy," there are 5 books, one of which is titled "The Restaurant at the End of the Universe")

Re: Why is there a normal galaxy sitting at the edge of the Universe?

#36
post #29
post #22

Earlier quoted context omitted.

No, 13 billion years is the age of the universe. The observable universe is a sphere with a diameter of ~93 billion light years (And is likely to only be a subset of the entire universe).

"Measurements made by NASA's WMAP spacecraft have shown that the universe is 13.7 billion years old, plus or minus about 130,000 years." https://starchild.gsfc.nasa.gov/docs/StarChild/questions/que... .

Whoa, that's crazy precise. They got it down to the tens of thousands?

If so, seems like they should write "13.700 billion" for the first part. I'm a little suspicious of this number as-is.

Looking for a source for those numbers, I found this[0]:

> While previous estimates were 13.7 billion years old, give or take 130,000 years, new predictions hone in with more precision- at around 13.77 billion years, plus or minus 40 million years.

Which is much less precise and feels a lot more believable.

[0] https://www.labroots.com/trending/space/18295/light-bang-rev...

Re: Why is there a normal galaxy sitting at the edge of the Universe?

#37
> The thing is, where they found it is not normal: The light we see from it left the galaxy 12.4 billion years ago, meaning we’re seeing it as it was when the Universe itself was only 1.4 billion years old!

It's not confusing at all. It's because the long-worshipped, conventional big bang theory is wrong. The universe doesn't have a beginning or end. It's eternal. The original sin of that theory is that it's tainted with forced space for a deity belief at the center and always has been. The universe cycles unevenly through phases of motion, it doesn't magically start from nothing and then 'die.' The conventional big bang theory is as bad as any other children's tale going, it's up there with Santa Claus.

We're going to find a lot more supposed abnormalities like this over time. They're not abnormalities, it's the entrenched incorrect theories that are the problem.

The universe (everything that exists) is drastically larger than we already think it is. Humans are arrogant, we didn't realize the extent of the micro world, and the same exact mistake is being made at the macro scale. What they think is a singular ~14-15 billion year old universe, is nothing more than one collection of galaxies, there are many more like it nearby (many as in trillions and trillions). The micro world was far smaller than we imagined; the macro world is far larger than we're imagining. It's the same mental mistake playing out, caused by the same arrogance. What's beyond the 'universe' that we can see so far? More massive collections of galaxies, similar to the one we inhabit that we mistakenly call the universe.

Re: Why is there a normal galaxy sitting at the edge of the Universe?

#39
post #22

I've always been puzzled by the estimated age of the universe at being 13 billion years. That's just the size of the observable universe, correct? Isn't there a future horizon beyond which light will not currently reach us?

No, 13 billion years is the age of the universe. The observable universe is a sphere with a diameter of ~93 billion light years (And is likely to only be a subset of the entire universe).

[deleted]

Re: Why is there a normal galaxy sitting at the edge of the Universe?

#40
post #22

Earlier quoted context omitted.

No, 13 billion years is the age of the universe. The observable universe is a sphere with a diameter of ~93 billion light years (And is likely to only be a subset of the entire universe).

Sorry to bikeshed, but I was struck by the word "likely" in your parenthetical. Are there models of the universe that predict our observable universe is _not_ a subset of the entire universe? How would one describe cosmological expansion in such a model?

Some weird geometry where space is curved into a four dimensional sphere. The sphere gets bigger, adding space between all the points. If the sphere is exactly the size of the observable universe, then the observable universe and universe would be the same thing.
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