The bounce v heat death

1. Jun 17, 2011

wolram

How many will argue that heat death is a better end to our universe rather than a bounce into a new universe

2. Jun 17, 2011

marcus

Our preferences don't seem to matter. I don't know of any indication that a future bounce is a possibility. A bounce may have occurred in the past---that is something to investigate by studying CMB data.

But there is no causal relation between past bounce and future bounce---they are completely separate issues.

Does anybody know why COLD DEATH (slowly freezing in the dark) is called "Heat Death"?

Actually "Cold Death" with stars burning out is not a bad prospect. Because if Civilization continues it will find ways to convert matter to energy that are much muuuuuuuch more efficient than stars.

A star only converts around 1% of its mass to energy, and then burns out. We can figure out how to get the other 99%.

Civilization will learn how to use any surplus mass (like asteroid rocks or dead star meat) and get the full E=mc2 worth of highgrade energy out of it.

So after the stars burn out we still have 99 times as long for civ to live and have fun.

So screw the "Cold Death" things look pretty good for sentient beings on the whole.

Louis Crane has some definite proposals for 100% conversion of matter to high quality energy. Doubt him not, and scoff at your peril, Woolie.
If you saw the photo of him that I saw, with his beady black visionary eyes, you would know what I mean.
Here is a snapshot, not the exact one:
http://www.fqxi.org/community/articles/display/127

Last edited: Jun 17, 2011
3. Jun 17, 2011

bcrowell

Staff Emeritus
Personally, my universe will end when I die.

Was the OP intended as a serious question, or was it a joke?

4. Jun 17, 2011

marcus

I think we have a choice in how to take the question and we can, as you point out, take it lightly as a joke. Some questions are like that. It can sound naive or trivial, or we can take it as a deeply serious one.

I know we have no choice about what kind of universe we live in, but suppose.

Suppose you had a choice of being born either (A) in a universe that would eventually stop expanding and would eventually collapse----hotter and denser even than the core of a star---or (B) in a universe like we think ours is, that will never stop expanding and must eventually be all cold dark and scattered.

Which would you CHOOSE other things being equal?

For the sake of argument, let's assume that the collapse in (A) would lead to a bounce and re-expansion----but so violent that structure is destroyed, you could not send a message to the creatures which might evolve and look at the sky on the other side. No message you could try to write in the sky for them to see would survive the bounce. It is beyond your power to communicate. But you may believe that there WILL BE conscious beings that arise at the other side of the bounce.

I know Wolram from years back. I think he is happy either way----take the question seriously or take it just as a funny thought. I remember him having a very good (English) sense of humor.

Personally I cannot say at this moment which universe I would choose to exist in. The good thing about (B) is you have a long loooooong time for civilization to survive in, and it will get smarter and smarter about using matter and converting matter to useful energy. Controlled black holes can substitute for stars. It is open-ended.

But there are good aspects to (A) as well.

Last edited: Jun 17, 2011
5. Jun 17, 2011

Bob3141592

I see the question as a chance to express a personal opinion of aesthetics. I agree with the notion that the universe ends when I die, at least to me, and I'm not sure about the rest of you. Sorry, I'm really not trying to take anybody with me, but who knows?

I prefer the simple Heat Death to the Bounce. I've always preferred asymptotic processes as being more natural and ideal. And like in Zeno's Paradox, I can accept the notion of a Heat Death scenario being also consistent with a Bounce ideology - just map the infinite span over which heat death occurs onto another bounded process and declare the second span as a finite bounce.

The Bounce kind of reminds me of the Tarski-Banach Paradox, where you can carve up one ball and reassemble it into two. Thank you very much, but one ball (and one universe) is enough for me. That's my Choice.

6. Jun 17, 2011

Bob3141592

And I know how to do it, at least in my dreams. CERN finds the Higgs boson, we learn how it works, and figure out a way to turn it off in the middle of a fusion reactor, thereby reducing the energy barrier to zero. We nest these "Higgs Reactors" inside each other fusing heavier and heavier elements. With the Higgs field off, even Iron does not inhibit our extracting out ever more energy.

Can I patent that yet, or do I have to submit a working model?

7. Jun 17, 2011

marcus

I differ with you on that score. My universe will not end when I die.

Wolram, when you ask this question about "heat death" it provides an opportunity to learn something, or to teach others it if you already know it.

Do you know about Hawking radiation from a BH? Do you know that the TEMPERATURE GOES UP AS THE MASS GOES DOWN? The temp is inversely proportional to the mass. Ben Crowell, or P Allen could give us the formula to find it exactly, if we wanted.

A little BH with the mass of a mountain would be glowing white hot.
You could feed it mass gradually little by little to keep it from evaporating----ie from converting all its mass to radiant energy.

By feeding it at just the right, steady, rate you could run a power plant off it.

Big black holes are relatively cold. But little BH are very hot and convert mass completely to energy and could be very useful.

I don't know if you know about that. If you are still around, please let me know if you understand about this. The problem that a surviving civilization will eventually face is how to produce LITTLE black holes---to keep warm with and run its power plants.

That is the essential thing that Louis Crane has often discussed. You remember Kea? The Kiwi woman who used to post here a lot. She knows Crane and has collaborated with him on one or more papers.

Crane says his strongest motivation in studying quantum gravity is to work towards understanding the art of making mini-BH----the kind that are small enough to be hot enough to be useful.

8. Jun 17, 2011

Bob3141592

That sounds remarkably reasonable and simple, though I think my Higgs boson nonsense makes for a better SF story.

I wonder if you would have any accretion disk issues with a mini black hole. At that point, it's mini enough to be the size of a nucleus or less, yes? Not much room for turbulent gas around that. Would there be weird effects if a mini black hole had an event horizon smaller than he wavelength of the particle it was absorbing? Could the particle itself become "turbulent"? Could we then make a diffraction grating out of rows of stabalized mini black holes that might not only refract the waveforms of particles but, by using the above turbulence, to teleport them?? Wait, I feel another SF story coming on.

9. Jun 18, 2011

marcus

Go for it!

http://www.fqxi.org/community/articles/display/127

And if you want to glance at his scientific articles here's the arxiv link
http://arxiv.org/find/grp_physics/1/au:+Crane_L/0/1/0/all/0/1
He is a prof in the math department at Kansas State. There are 35 papers (two pages, 25+10) to get the earlier ones click on the "next 10" link at the bottom of the first page.

Among the 35 are several about using small BH as energy sources.

Last edited: Jun 18, 2011
10. Jun 18, 2011

narrator

I think the whole idea of entropy plays a big role here. And if mass means energy, then combine mass, energy and entropy until perhaps you have a sea of exotic particles... where they go after that, could be towards a bounce or even conversion to something else entirely.

As a layman, I don't think entropy is infinite. But if it is cyclic, then I think its reverse must be far swifter.

As for the universe dying when I die, if we're all made of star stuff, then maybe we become something exotic ourselves.. :p