Why can't the Universe be eternal?

You probably won’t appreciate me saying this, but I’ll say it anyway.
The one aspect of life that pulls me toward the belief of a deity is the thought of eternity, especially negative infinity. It’s hard to grasp the fact that time is infinite, and if it is, then how can we count it? Does everything really happen for a reason and can we trace every reason back to one first reason? It’s like what Thomas Aquinas said.
And good luck finding someone who can actually prove to you that the universe had a finite beginning but can continue infinitely far into the future…

Every time we tell the universe what it should or cannot do, I think it laughs those big booming laughs that produce supernovae

@dxs Why would I not welcome reasoned questions? But bear in mind I cautioned that common sense, steeped in incredibly limited and brief human perception, it powerless to explain the vastness of even the known universe, or the bizarre nature of everything that makes it up at the quantum level. I have no problem conducting a thought experiment where I come upon a ruler that is in fact infinitely long, but that has marks on it delineating millimeters and meters. I see no reason why it would be harder for me to paint such marks on an infinitely long stick than to paint them on a stick one meter long.

@drhat77 I am most definitely in agreement with you on that.

all I can do is show you my birth certificate.

@ninjacolin Ha! I already believe you and I aren’t eternal, at least as far as our lives in these bodies go. But I also believe neither of us is the Universe.

I think that might just be your common sense opinion ;)

Perhaps the answer lies in the notion of “as we know it”.

Were we all transported to 14 billion years in the past, we would not recognize that universe. I suppose we would not recognize 14 billion years in the future either. The universe as we know it would have ceased to exist. But that only means it has changed, and not necessarily ended.

“If you have an argument as to why an infinitely old Universe is impossible, make sure it’s a solid one”

I cannot say that the universe will end. But I can say that our universe is expanding, and all matter decays. Thus, I can foresee a possible future where expansion and decay dissipate the universe into a state where nothing could be detected. That doesn’t mean something wouldn’t be there. It just means we couldn’t detect it if there were… Such an argument presents obvious paradox of the observer being capable of existing in such an environment.

Perhaps it’s more organic. Similar to the human body, where not one cell exists from seven years ago. An argument could be made that the person you were in 1990 does not exist any longer.

The Universe is a construct of human minds to describe what we see. Since everything we experience has a beginning and an end, we expect that is universal.

What many people don’t realize is there is no such thing as a beginning and an end in nature, either, there is just change.

The best reason to think that the Universe is finitely old that I know of is the popular interpretation of the observed red-shift. When we observe objects in the Universe, they appear to be receding from us. Thus we reason that the Universe is expanding. This implies that at one time, the Universe was more compact, and that one time it might have been a single lump of stuff. From this, cosmologists have produced the Big Bang hypothesis, and postulated the Big Bang as the beginning of the Universe. Other cosmologists have claimed that the Big Bang event could be part of a cycle of expansion and contraction. Meanwhile, cosmetologists are saying you shouldn’t use too much product.

@ninjacolin I cannot prove you are wrong, but you can’t prove I am either. :-)

@RealEyesRealizeRealLies That’s an interesting point. For questions like this, it works best to think in thought experiemnt mode. So let’s allow a disembodied, intelligent point to be there in the far future to observe a universe approaching infinite entropy. Could that be the trigger of the next big bang. Quantum mechanics says it absolutely could—in fact, some top physicists assert that nothing else could possibly result. That gets us pretty close to your human body analogy. We’re still here, but none of what we were made of 7 years ago is here with us now.

@YARNLADY Amen to that.

@rexacoracofalipitorius The Big Bang isn’t a postulate, it’s a legitimate theory. The postulate predicted a large number of things, all of which have been independently confirmed by thousands of observers, many intent on proving the postulate wrong. The existence of the Cosmic Microwave Background Radiation, its exact temperature, its structure and location all flowed from relativistic equations calculating what would remain if there were a big bang.

I don’t know of any credentialed cosmologists who still subscribe to the cyclical expansion/contraction postulate. That’s been ruled out. But a big crunch is not the only thing that that could conceivably initiate another Big Bang. What appears to be a pure vacuum is actually a seething, boiling cauldron of quantum fluctuations in which particles poof into and out of existence continually at a bewilderingly rapid rate. So enough entropy could be just what it takes to touch of the next Big Bang. If so, then previous entropy of a Universe dying heat death might have triggered our Big Bang.

@YARNLADY That’s a very interesting perspective.

@ETpro “The Big Bang isn’t a postulate, it’s a legitimate theory.”
Where’s the conflict? It was postulated according to observed evidence (red-shift) and has been validated by further observation. Legitimacy doesn’t make it not a postulate.
I wasn’t aware that the cyclic theory had been ruled out, but https://en.wikipedia.org/wiki/Cyclic_model seems to back you up on that and your following statements.

@rexacoracofalipitorius Look up “hypothesis, postulate and theory“http://community.switchfoot.com/index.php?/topic/11055-hypotheses-theories-and-postulates/. One emerges from the other, but they are nothing like being the same things. You emerged from a zygote. You are not currently a zygote.

@ETpro I’m sure Princeps is very intelligent, but I’m afraid I can’t accept that forum post as an authoritative source. If we do accept it as authoritative then a ‘postulate’ never becomes a theory, but only serves as a basis for argument.
The sense in which I was using the word was according to sense 2 here. There was no proof of expansion at the time. Inflation was suggested to explain observations. My usage may have been incorrect: maybe no one ever “postulated” rather than “hypothesized”- but I maintain that if something was postulated, then it’s a postulate. If there’s evidence for it and it explains other stuff, then maybe it becomes a theory. The two are not incompatible.

@rexacoracofalipitorius Here’s the pertinent dictionary definition of postualte. ”(Mathematics) Logic Maths an unproved and indemonstrable statement that should be taken for granted: used as an initial premise or underlying hypothesis in a process of reasoning.” If string theory is true, then the underlying maths say that M Theory would be true as well. But currently, neither String Theory not M Theory can be tested in any way we have been able to conceive. To be an hypothesis, something must be clearly testable and falsifiable. Again, to the dictionary. Hypothesis: “A tentative explanation for an observation, phenomenon, or scientific problem that can be tested by further investigation.”

Postulates often lead to on or more hypotheses which can then be tested. They are the fundamental building block of Scientific thought. But until they suggest hypotheses that can be tested, and pass those tests here and there, even when tested by naysayers, they are nothing more than an interesting hunch that might someday bear fruit, and then again might not.

It can.

Stating that any one thing cam be eternal is a scientific and religious cop out.

@SecondHandStoke I’d love to see your proof for that.

@ETpro

As you might expect I can’t give you much on this one.

I will say this:

The eternal quality of individual things is a human construct.

It always was and it always will be. Class dismissed!

@SecondHandStoke & @kritiper Class is dismissed when I say so, or when you drop out, whichever comes sooner. :-)

@SecondHandStoke Why must the question of an eternal Universe have ANYTHING to do with humans, other than the fact it is a human that’s asking? How are we to know that 10 million other intelligent species out there aren’t asking the exact same question? I call human conceit on that answer.

If we agree there was a “This” (Big Bang, for instance), why am I not permitted to ask what came before that? If we agree the observable universe appears to end in heat death, why am I not permitted to ask what comes after that? Never mind that @SecondHandStoke would say there was no answer and @kritiper would say there was. Neither of you have a clue as to the truth of that. Why is saying “I don’t yet know.” so tough?

Why is saying “I don’t yet know.” so tough?

I don’t know… seems to be a general phenomenon though…

People rather accept simple understandable statements that are untrue than complex nuanced answers that are.

To every complex question there is always a simple answer, that is attractive yet untrue.
Most complex questions come with complex answers, or even without.

@ETpro – AH! But I CAN base my knowledge of what I DO know and CAN observe for an answer! No point in deciphering an answer based on admitted unknowns. What’s the (rhetorical) point?

@ETpro

I might change my answer when a truly immortal extraterrestrial species confers with us.

In the same way you take issue with my taking an exclusively human view I submit that our particular universe is finite and if considered exclusively would be part of a limited view.

What about all the other universes existing before, during and after ours?

As far as what came before our universe the answer has already been provided by Stephen Hawking:

“It’s a meaningless question.”

@kritiper The point is that if you tell yourself that you know what you don’t actually know, you never look to correct your error.

@SecondHandStoke Let me be so bold as to disagree with Dr. Hawking on that point. It’s not a meaningless question till we know there is no answer to it, and we do not know that.

@ETpro – Oh, I keep looking for answers. That’s part of knowing what I know and applying it logically. To constantly refine what IS known. But to not know and assume you can’t know isn’t very logical because your assumption that you can’t know causes you to lose sight of the obvious. But keep looking!

No person should expect to receive or deliver any believable answers to such questions when the answer expectation quotient has obviously been set so high.

@kritiper Bear in mind that there is a large percentage of humanity, all theists, who claim absolute a-priori knowledge that the Universe can’t possible be eternal because nothing can, and therefore their (name your favorite creator deity here), who just happens to be eternal, OBVIOUSLY created the Universe. The question isn’t “Is the Universe eternal.” If it were, then you are right, none of us could honestly answer it. But as asked, what’s so hard about saying, “I don’t know, maybe it is.”?

@ETpro

Great Question.

@SecondHandStoke Ha! Glad to hear you feel that way. You and I didn’t get off the the greatest of starts in other threads.

Time, that’s all.

I wasn’t worried.

Besides, there has to be some debate.

I’m not interested in being a member of a forum that’s just one big circejerk.

@SecondHandStoke Oh, I can assure you that’s not what you’ve entered here. :-)

@ETpro – OOPSIE! You forget that I don’t have (or believe in) a “favorite deity creator.” Only theists (and partial theists) can claim the universe as (perhaps) being constructed and time limited by some fantastical “deity.” To answer the question, it can be eternal, it will be eternal, because it has always been so. And always without the influence of some great all-powerful unseen spook.

@kritiper Given my own forgetfulness, I will never be the first to cast a stone.