Does Feynman's Multiple Histories mean what I think it does?

[Tailspin]

As for the universe at large, it must end eventually, one way or another. That is almost certain. But the most likely scenario - the "heat death" - will only happen a very long time after our Sun is dead and gone.

Why? Why must it end? Aren't you the one who's been telling me that all theories are provisional and think critically? Are you now saying I have no choice but to believe the end will come?

Also in that episode with Brian Cox, I think I might have skipped over the into but I don't remember him EVER saying anything in his show was provisional.

 

[Tailspin]

So, if I was you, I'd probably worry more about humans surviving for the next few billion years than I'd worry about the ultimate death of the universe as a whole. Earth is just one minuscule speck in a mindbogglingly huge cosmos, but we can go anywhere else. We're stuck here, for the moment.

This is why I don't talk about this with just anyone. They all say it's inevitable, we have more immediate problems, I'm a fool for having these feelings and I shouldn't have them.
I thought you were different.

 

[James R]

Tailspin:

Why? Why must it end? Aren't you the one who's been telling me that all theories are provisional and think critically? Are you now saying I have no choice but to believe the end will come?

Yes, all theories are provisional, so we should keep an open mind. But not so open that our brains fall out (as they say).

All the evidence suggests that our universe had a beginning. It is, of course, possible to conceive of a universe that did not have a beginning.

All the evidence also indicates that our universe is changing over time. It is not the same now as it was 10 billion years ago. Therefore, it is unlikely to be the same 10 billion years from now. Again, however, it is possible to conceive of a universe which remains more or less the same over time.

Our best theories - guided by the best observational evidence - suggest that, given that the universe had a beginning and is changing over time, it will have an end. It is, however, possible to imagine an endless universe.

The big bang theory is a fairly recent invention. Before it became widely accepted, there was a popular alternative, called the Steady State Theory. That theory proposed that the universe would look more or less as it does now for all time, that it had no beginning and would have no end. That theory ran into some problems when it was discovered that the universe is expanding. If it is expanding, then the only way it could possibly continue to look the same (e.g. have a constant density of matter) would be if new matter was spontaneously and continuously being created. However, no viable mechanism has been suggested for that and, more importantly, the observational evidence strongly suggests that it is not happening.

Einstein, when he formulated the general theory of relativity, believed in something like the steady state theory. He even went so far as to build a theoretical mechanism into his theory that would account for the failure of the universe to collapse under its own gravity. For quite a long time, that mechanism wasn't needed, especially after the big bang theory came along. These days, it turns out that it is needed for a different reason altogether: to explain why the universe's expansion is accelerating rather than slowing down, as would otherwise be expected. (It is the data that tells us it is accelerating.)

So, when it comes down to what you ought to belief, that's up to you. You can believe in the discounted Steady State theory if you like, but be aware that none of the observational evidence supports it and there are theoretical problems with it. Alternatively, you can believe our best current theoretical models, which are based on lots of real-world data and some carefully tested theory. Of course, even the best models are provisional. We don't know what we don't know. Maybe we'll discover something totally new and unexpected tomorrow which will upset the apple cart.

Whatever you believe, there's very little point in fretting over it, unless you're planning on becoming immortal some time soon. In terms of your own life span, or that of any children you have, you won't be around for anywhere near long enough to see the end of the Earth, let alone the end of the universe. If I were you, I'd worry about more pressing issues, if you feel like you need to worry about something.

Also in that episode with Brian Cox, I think I might have skipped over the into but I don't remember him EVER saying anything in his show was provisional.

I think I have already talked about that.

They all say it's inevitable, we have more immediate problems, I'm a fool for having these feelings and I shouldn't have them.
I thought you were different.

Tell me why you're worried about how the universe will end.

 

[Tailspin]

Tailspin:
So, when it comes down to what you ought to belief, that's up to you. You can believe in the discounted Steady State theory if you like, but be aware that none of the observational evidence supports it and there are theoretical problems with it. Alternatively, you can believe our best current theoretical models, which are based on lots of real-world data and some carefully tested theory. Of course, even the best models are provisional. We don't know what we don't know. Maybe we'll discover something totally new and unexpected tomorrow which will upset the apple cart.

Whatever you believe, there's very little point in fretting over it, unless you're planning on becoming immortal some time soon. In terms of your own life span, or that of any children you have, you won't be around for anywhere near long enough to see the end of the Earth, let alone the end of the universe. If I were you, I'd worry about more pressing issues, if you feel like you need to worry about something.

Tell me why you're worried about how the universe will end.

Firstly, as I've already explained, the statement "As for the universe at large, it must end eventually, one way or another." is exactly the kind of statement I can't help but take literally. It has an air of authority, like it's been proven beyond all doubt and it leaves no room for doubt or any other interpretation.
Like "You must obey the law" "You must be careful with your medication." or "You must constantly breathe air." You wouldn't consider those statements to be provisional would you?

Secondly I never said I believed the universe was unchanging or static, I don't. I was asking if it was a certainty if it would all end and nothing would ever come after it.

Thirdly I will tell you why I'm worried about how the universe will end. But first let me say it really hacks me off every time anyone asks me that. But if you must know...

Its said and seems to be accepted as irrefutable fact and an inevitability by almost everyone that not only will all the stars in the universe burn out but the universe will lose it ability to make any more. Leaving the entire universe cold, dark and incapable of supporting life. There will be nothing but nothingness, a lifeless void and it will stay that way for all eternity.
Now at this point, when I explain my feelings on this issue to someone, I would think that would be explanation enough, also I would think it obvious that the end of all things . But no, people are baffled by why anyone could possibly be upset about this fate for all creation. They ask why it bothers me. Well if someone had just lost their child in a horrible accident, would you ask why it bothered them? When I first learned of this I felt horror, dread, and a sense that everything was meaningless. I didn't think about it to form those feelings they were just my first and natural response and I consider them reasonable and the only correct responses to have.
But if you need me to actually explain further...
All human life and every other form of life will go extinct, every trace of our existence destroyed. There will be no memory of humanity and no one to remember it. Countless generations of building, creating, investigating, fighting for what they believed in, toiling to uphold their world and fix the problems that plagued their society, ultimately all comes to nothing. I'm one of those people who would like to leave a legacy, make their mark in a way that will endure. But with this hanging over me I don't see any point to anyone doing anything. The thought of an inevitable and permanent end to everything makes me want to die!

But what hacks me off, fills me with frustration and anger is I can't get any sympathy from anyone on this, not even from my own parents! Like you the believe this is what's going to happen to the universe and they're not bothered by it at all. I confided in them how I felt looking for some comfort. Instead I got bewilderment as to how anyone could have these feelings. I found myself explaining it over and over, which was painful enough, and they still didn't get it.
They said there was nothing I could do about it so why worry about it? Well if there was something that could be done about it I wouldn't be so upset.
They said I'd be long dead by the time it happened so it wouldn't effect me. Well I KNOW THAT and I get the logic but my feelings just don't change, it has no effect on me whatsoever. Besides I'm not concerned with just myself but the continuation of life, humanity and it's legacy. Incidentally you said humanity has more pressing concerns, well this trumps ALL of them.
They said my way of thinking did me no good at all, well I don't care if it has no practical benefit to me, that's not what I'm concerned with here.
Everyone, including my parents, can't imagine how I could have these opinions, they say they're irrational, illogical, do me no good, don't matter and I shouldn't have them. They just look at me like I'm a fool, they don't get me on this at all. Well I don't get them on this, I think my opinions and feeling on this are perfectly correct and reasonable and it's the people who are fine with the end of the universe who are insane fools! I get so angry when I talk about this because it brings up all my feelings of frustration, resentment, dread and despair along with isolation and loneliness because I feel I can't talk about this with anyone because they'll just say what my parents said or laugh at me. Well to you and everyone else who does that, I say if you don't agree with my point of view then, as decent human beings, the least you can do is accept this bothers me and respect my feelings!

And I hope you apricate this as it took a lot of effort to get this out as well as my whole evening.