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The universe has already made almost all the stars it will ever make

nautil.us

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Re: The universe has already made almost all the stars it will ever make

#91

Post by krylon »

lemonberry wrote: post #47
stackbutterflow wrote: post #36

Earlier quoted context omitted.

There's a video on that. The end of the universe: https://youtu.be/uD4izuDMUQA This is so weird to think that for most of its life the universe will be empty and cold. Like what's even the point of all this, of life, of us, if in the end nothing matters, everything decays into nothingness.

"Nothing matters" This is true in the biggest sense of the word. But it's also false. We all have things that matter to us and the various communities that we belong to. In some ways, to me anyway, it's very liberating: life as a blank canvas to imbue it with the meaning we want on. That won't resonate with everyone or even most people, but it's motivating for me.

Albert Camus wrote a beautiful (IMHO, at least) book about it, The Myth of Sisyphus. His point, as I understand it, is that nothing matters in the sense that the universe is vast and empty does not care what happens to you or me. But that also means we get to choose what matters to us.

Life has no meaning, but it has meaning to us, and we can, in a way, choose what we want it to mean. I agree, I find this perspective very liberating and positive, but I can see how some people might find it bleak.

Re: The universe has already made almost all the stars it will ever make

#92

Post by MAGZine »

s1artibartfast wrote: post #46

It is important to contextualize what almost all means in this context of a vast and possibly infinite universe. It leaves an incomprehensible number of stars yet to form. It also leaves open a backdoor for a star forming Renaissance if blackhole activity dies down in another 10 billion years.

It is important. Based on a lot of comments, people seem to think "oh, well, universe dead, I guess."

Which is far from the truth. There are still millions of galaxies forming millions of stars, and that is going to continue into the indefinite future.

This is saying that statistically, the younger the universe, the more stars that are created. And they bright, hot, short-lived stars, that, once dead, will give birth to many new stars (who will also generally be bright and short-lived, just less so).

This means that the universe produces a great deal of young stars shortly after its inception, but that eventually gives way to many more long-lived stars that are actually habitable for life.

The universe is very much in its hayday, right now. We're living evidence of it.

Re: The universe has already made almost all the stars it will ever make

#93

Post by losvedir »

roberthahn wrote: post #73
madmads wrote: post #15

Earlier quoted context omitted.

I mean the universe is so incredibly vast that even if we figure out how to travel at the speed of light, we'll only ever get to see a small fraction of it. I don't think we'll have to worry about running out of places to explore.

So, about that. One of the weird things about General Relativity is that if we COULD travel at or near the speed of light, then time dilation and length contraction will conspire to enable a trio to the end of the observable universe in 30 years. So we could definitely explore the universe, we just have no way to share what we discover with our friends back home.

Still, the observable universe is only a small fraction of the whole universe (we believe, based on spacetime curvature, I think).

Re: The universe has already made almost all the stars it will ever make

#94

Post by unyttigfjelltol »

stackbutterflow wrote: post #36
misthop wrote: post #12

Wikipedia has a page on the Timeline of the far future[1]. It lists a ton of physical and cosmological things that are predicted to happen based on our current understanding of physics. A really fun read that always takes me down a rabbit's hole of phenomena wikipedia pages. [1] https://en.wikipedia.org/wiki/Timeline_of_the_far_future

There's a video on that. The end of the universe: https://youtu.be/uD4izuDMUQA This is so weird to think that for most of its life the universe will be empty and cold. Like what's even the point of all this, of life, of us, if in the end nothing matters, everything decays into nothingness.

I've been enjoying the kurzgesagt collection of videos[1] which discusses the same phenomena, and how we literally can never travel to large swaths of the universe.

[1] https://m.youtube.com/watch?v=uzkD5SeuwzM

Re: The universe has already made almost all the stars it will ever make

#95

Post by rbanffy »

stackbutterflow wrote: post #77
kibwen wrote: post #72

Earlier quoted context omitted.

Is there an axiom of your personal philosophy that causes you to conclude that something must persist for infinite time in order to possess meaning?

I can try. If the result of doing something vs doing nothing is indistinguishable after a certain time, does it matter that it ever happened?

It depends on your perspective. If you experience time as a spacelike dimension, you can look at this part of spacetime and be amazed at the rich tapestries we, the weirdos who perceive time as timelike, weave with our lives.

Re: The universe has already made almost all the stars it will ever make

#96

Post by rbanffy »

haxiomic wrote: post #61
marton78 wrote: post #54

Earlier quoted context omitted.

Obligatory link to Isaac Asimov's wonderful short story "The Last Question" which explores this topic: https://www.physics.princeton.edu/ph115/LQ.pdf

I have never read this before, thank you :)

It's one of my all-time favorites.

Re: The universe has already made almost all the stars it will ever make

#97

Post by rbanffy »

foxyv wrote: post #45

This makes me wonder, how many sparks of life and ancient civilizations have been wiped from the universe by the birth and death of stars. How many supernovae have violently ripped them from existence. How many rogue stars have cooked them to molten slag. What a small and fragile thing humanity is in the face of these forces.

People pointed to Asimov's Last Question, I'll point you to Clarke's The Star:

https://sites.uni.edu/morgans/astro/course/TheStar.pdf

Re: The universe has already made almost all the stars it will ever make

#98

Post by rbanffy »

benlivengood wrote: post #53
boxed wrote: post #14

Earlier quoted context omitted.

The important part is to disassemble stars. They are burning all the hydrogen way too fast.

Or dumping them into supermassive black holes. They'll survive a googol years or so, and feeding matter in will produce plenty of energy.

And when we run out of matter to feed, we can always steal energy from their rotation with the Penrose process.

Re: The universe has already made almost all the stars it will ever make

#100

Post by kibwen »

stackbutterflow wrote: post #77
kibwen wrote: post #72

Earlier quoted context omitted.

Is there an axiom of your personal philosophy that causes you to conclude that something must persist for infinite time in order to possess meaning?

I can try. If the result of doing something vs doing nothing is indistinguishable after a certain time, does it matter that it ever happened?

That's a good question, and I'm certainly not trying to suggest that there exists a right answer.

My thoughts are that the formulation assumes the perspective of an observer outside of the system, treating the system as a sort of black box, waiting for the system to produce some sort of signal. And because our current understanding of heat death means that the "signal" will always be something indistinguishably meaningless, the outside observer (who cannot inspect the inner workings of the system) is free assume that, from their perspective, nothing of meaning occurred inside the system.

But even if we assume the above to be true, this is still compatible with an alternative interpretation: from the perspective of an observer inside the system, we may distinguish differences in the system and may find meaning in those differences. Although that's "may find meaning", not "will find meaning"; determining the meaning of one's existence is intensely personal. However, given the above axiom, I don't believe it precludes finding meaning.

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