I'm working on a science fiction novel, a sequel to the best-selling Dark Space series, and I would like to include some reasonable (but fictional) possibilities for how the universe might cycle from expansion to contraction, resulting in a theoretically endless cycle of singularities/big bangs.

This is an age-old question, and far from solved in science, but ideally I would like to inject a fictional force/scenario that could cause the transition from expansion to contraction, and one which does not contradict any currently well-established science.

One hypothetical scenario that I found interesting, is to propose that our universe exists in a configuration of universes that take turns expanding and contracting. When one expanding universe reaches the bounds of another expanding universe, the one with the greatest force of expansion will push back against the space-time barrier of the other one, resulting in its contraction. Once a universe can be forced into contraction, however slowly, gravity does the rest, bringing it back to a singularity.

This seems a logical possibility to my untrained mind, but I wonder if such a configuration could be reasonably expected to go on forever, and whether or not such a system of universes would even work in practice to create the necessary transitions from expansion to contraction.

I'm looking for feedback for my fictional model, and any other theoretical models for how expansion could turn to contraction. By all means refer me to actual research on the subject.


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  • $\begingroup$ You might be interested in reading about ekpyrotic models, en.m.wikipedia.org/wiki/Ekpyrotic_universe $\endgroup$ – Andrew Jan 14 '17 at 22:46
  • $\begingroup$ Thanks for the reference to wikipedia re the ekpyrotic universe. Very interesting reading! $\endgroup$ – Jasper T. Scott Jan 15 '17 at 2:46
  • $\begingroup$ Here, I retagged it for you. Feel free to change tags as you see fit, but don't use hard-science for this, OK? $\endgroup$ – Mołot Jan 15 '17 at 8:41
  • $\begingroup$ @Andrew Well done! Referring the OP to ekpyrotic cosmology was my first thought on seeing this question. Good to see it's already been done. $\endgroup$ – a4android Jan 15 '17 at 10:18
  • $\begingroup$ Can you link to the book series you mentioned? $\endgroup$ – JDługosz Jan 17 '17 at 17:07

One hypothetical scenario that I found interesting, is to propose that our universe exists in a configuration of universes that take turns expanding and contracting.

For the distinction between universes to exist, they need to be different in fundamental ways, otherwise obviously it would all be the one universe.

One way different universes could exist, actually the only way, is if the physical constants in that universe were different than ours, so the speed of light is faster/slower, the fine structure constant is not the same as "here", there are a host of ways in which the other universe could be different.

If you want life, but not as we know it (Jim) to exist in these other universes, it may be that you will need to develop the idea that the physical constants are different, but that the differences cancel each other out.

There was an article on this in Scientific American from about 10 years ago, in which this idea was explored. For example, if the up quark was a bit heavier, then the mass of the down quarks was a bit lighter, so that overall a proton or a neutron was the same total mass, charge.....in both universes.

My point is that you could exploit this necessary difference between universes to produce the force you are looking for.

How??? You are the writer.....

Good luck with the book.

  • $\begingroup$ Very good points about different universes requiring alternate values for physical constants. I'll have to give that some more thought to be sure alternate universes will actually be beneficial to my fictional world. Alternatively, having our universe existing in a configuration of self-contained bubbles or pockets that take turns expanding and contracting would work, too. $\endgroup$ – Jasper T. Scott Jan 15 '17 at 2:48
  • $\begingroup$ Sorry, I was a bit OTT in my original draft, but I grew up on SF (I can't use Sci-Fi, I hate the term). Forgive me telling you how to write your book but as a possible reader, (and buyer :) I have a stake in it.... As far as force goes, I would look up the latest, necessarily extremely speculative ideas on what dark energy is, and try to work that in as the cause. $\endgroup$ – Countto10 Jan 15 '17 at 3:13
  • $\begingroup$ Every potential reader and his cat knows the dark energy buzzword, it sounds as mysterious as it really is, it could be capable of anything. Look up the pop sci books, some authors I won't name will speculate on very little evidence or even search through this site, we have had all sorts of notions as to what it could be. Sorry, you obviously know your readers better than I do and how much you have to balance between entertainment and education/sense of wonder.The pop Sci books deliberately avoid detail re DE, (because really they haven't a clue), which is to your advantage. $\endgroup$ – Countto10 Jan 15 '17 at 3:16
  • $\begingroup$ Dark Energy, yes, I have avoided using that as my hand-waving explanation until now, but I think that will suit my purposes nicely for some of the unexplained phenomena in my next book. Thanks for reminding me! Also, your original draft was hilarious ;), and I do hope you'll check out my work! Thanks again for your help speculating with me. $\endgroup$ – Jasper T. Scott Jan 15 '17 at 16:22
  • $\begingroup$ Delighted to chat. The guys here have suggested ekpyrotic cosmology, the pyro snippet might be a clue to how dramatic that could be. One last suggestion is to setup a throwaway gmail account and subscribe to every potential internet source, from hard science sites through odd, all the way out to extremely odd....I have read enought to know that all the good SF gimmicks have been used up, so it must be more difficult to write new material.... (And about agents, make them work for their blood money, 10 % max :) anyway, the very best of luck. $\endgroup$ – Countto10 Jan 15 '17 at 16:48

This is an age old question, and far from solved in science, but ideally I would like to inject a fictional force/scenario that could cause the transition from expansion to contraction, and one which does not contradict any currently well-established science.

There's still some possibility for the Universe to turn out to be closed, i.e. its mass is enough to stop its expansion and begin a gravitational contraction. The so-called dark matter explanation is not at all established "beyond any reasonable doubt".

Or you could even introduce a "slight" handwave and introduce a low-order term in the gravity equation. It has already been proposed (and struck down in favour of the "dark matter" explanation) to explain the rotational speed of galaxies, but you could re-introduce it in conjunction with a phase change in the characteristics of space. This kind of phase change has already been proposed to allow what is called the inflationary stage of the Big Bang; another phase change could take place when (or whenever/wherever) matter density falls below a critical point. So what now seems an open Universe would turn out to be actually closed.

At that point, you have your gravitational collapse.


I found a way to have expansion turn to contraction in Howard Bloom's bagel-shaped universe. See: http://howardbloom.net/the-god-problem-how-a-godless-cosmos-creates/big-bagel-theory/ but I still have a few doubts about this theory--if true, the next big bang would occur along the equator of the bagel, (where one might slice it open to spread cream cheese ;). This wouldn't be a singularity, but more like a ring/band. How might all of that energy end up back where started, in the hole in the center of the "bagel?" I read something about the equator/rim of the bagel being exactly like the center due to a topological trick, but I can't see how that would be the case. Essentially the next big bang would look like a ring of fire spreading outward toward the original starting point at the center of the bagel. If the matter/energy manages to funnel back into the bagel hole where it originally exploded from, then you could get another singularity and another big bang. That seems like a reasonable conclusion, but first you get the ring of fire spreading back to its origin, and Howard Bloom seems to think the next big bang IS that ring of fire. What am I missing?


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