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Could dark energy "simply" be from multiple distant universe-scale mass black holes, that are there "all-around" the big bang? Scattered apparently randomly, throughout infinity (or a very big distance)

If not black holes, some other kind of concentrated mass, but in the order of magnitude of the mass of the big bang's "universe". So sextillions of solar mass (M☉).

These black holes, let's call them Big Bang Massive Black Holes (BBMBH), because "supermassive" and "ultramassive" is taken.

Visual representation

Here's a visual representation of the black holes and gravity effects:

BigPicture

Shell theorem

I got some comments about the shell theorem, so let me explain why I don't think it applies here:

There's the big bang in the "center", and there's multiple objects around it, randomly distributed. If there was just one layer around the center, then yes it would probably apply, like this:

ShellTheorem

But if you look at the visual representation above, it doesn't apply because the gravity is not symmetrical (or spherical).

It would only apply if the black holes would be evenly distributed:

ShellTheorem2

Context / Assumptions

Firstly, this doesn't change anything that we currently agree on: the Big Bang and its age, the effects of dark energy, etc.

Here are some assumptions that make the idea (possibly) work:

  • The full universe is infinite, or much bigger than the known and observable universe
  • The big bang is not the whole universe. It's just a small part of it: there's more mass around it.
  • The big bang is not the start of the whole universe.

Dark Energy

The infinite collection of BBMBHs described above would explain the dark energy, being gravity on BBMBH scales.

Some maths

The universe is currently around 28.5 gigaparsecs (Gpc).

Let's say that the average distance between all BBMBHs is around 700 Gpc. That would mean there's a bunch of BBMBHs pulling everything from "our big bang" towards them.

At first, even a black hole of 10 sextillions of M☉ wouldn't have much pull from 700 Gpc. Also considering that there are BBMBHs all-around, so they're pretty much all negating each other (as they were all in equilibrium before the big bang).

From the current observations humanity made, it looks like at around 8-10 billions years old, the big bang's size expansion started accelerating. From around 3 Gpc.

At 697 Gpc, BBMBHs could start to gradually have a non-negligible pull, accelerating with time. Also, the pull from the other BBMBHs on the other side would now be from 703 Gpc, not 700, so that's an additive effect towards the expansion of the Big Bang, adding to the fact that the peripheral galaxies would be less pulled from the big bang's mass, the further away from its inception it would be.

1D Estimation

I made a quick 1D estimation to see if it would make sense, and even though it's a gross over-simplification, it seems like it could be possible.

Here's 2 graphs (one for the first 4 billion years and another for the rest), followed by more details: chart-BBMBH-Dark-Energy-5G chart-BBMBH-Dark-energy15G

Using 2 BBMBHs at 1400 Gpc from each other, with a big bang starting between them, with a peripheral galaxy moving at 1c after 370000 years (using current estimates), then slowing down due to the mass of the other matter from the Big Bang, and then accelerated by the closest BBMBH located at 700 Gpc at first, I get:

  • 0.56 Gpc at 8 billion years old
  • 1.64 Gpc at 10 billion years old, and
  • 14.15 Gpc at 13.78 billion years old,

which is close to the agreed upon sizes of around

  • 1.5 Gpc between 8 and 10 billion years, and
  • 14.13 Gpc now (~13.78 billions years)

Results1D

More context that might be irrelevant / out of scope

If the big bang isn't the beginning of the universe, what is it?

What I'm suggesting is that "the big bang" might be a BBMBH that exploded (similar to big stars going supernova)

So the idea is that our big bang is actually not "the big bang", but "a big bang".

The big picture

In the grand scheme of things, there would be an infinite (or very large) collection of BBMBHs.

Then the occasional "big bang" of one of the BBMBH, resulting in a blip of chaos, absorbed by all other BBMBHs eventually, or forming another one, in an unimaginable time scale.

Conclusion

I feel like it's possible? I don't know if it's probable, so that's why I'm asking. Any insights?

P.S. Sorry for my English, my native language is French, but I thought I would have more chances of finding answers in English, and also I mostly learned astrophysics from English sources.

Edit: Removed a bunch of information and restructured the question and details Edit 2: Adding the shell theorem

MGamsby
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    You crammed a lot into this question, most of which seems irrelevant — in particular, all this theory about the growth of black holes. That makes it less likely to get any interested responses. Can we summarize your question by restating it as: "Suppose the observable universe is actually surrounded by some very distant but extraordinarily massive black holes. Could these explain dark energy?" The age of those black holes (or even the fact that they are black holes) and how they formed are entirely irrelevant to this simpler question. – Mike Nov 27 '23 at 17:16
  • Big Bang has no spatial or temporal "center". Think about it like balloon 2D surface has no center in it, but rather inside in 3D space, which makes no sense for "hypothetical 2D creatures" supposedly watching balloon expansion on it's surface. Likewise, universe IF would have a spatial center, then it probably would be in a 4D hyper-cube, which to us 3D creatures does not make much sense. Hence, calculating object distance from "universe center" has no point. – Agnius Vasiliauskas Nov 27 '23 at 17:18
  • Mike: Thanks, I didn't see it like that, I removed some information and changed the title – MGamsby Nov 27 '23 at 17:27
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    Also, "We deal with mainstream physics here. Questions about the general correctness of unpublished personal theories are off topic, although specific questions evaluating new theories in the context of established science are usually allowed. For more information, see Is non mainstream physics appropriate for this site?". – PM 2Ring Nov 27 '23 at 17:32
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    A major objection to your proposal is the shell theorem. See https://physics.stackexchange.com/q/43626/123208 – PM 2Ring Nov 27 '23 at 17:38
  • Agnius Vasiliauskas: I was doing a gross oversimplification. I was thinking that we can have a decent estimation of the 3D center of a balloon from a 2D surface. And I was talking about the center to determine an approximate radius. Since I'm a 3D creature, maybe there's something I don't get from 3D to 4D though, interesting to consider. Thanks. – MGamsby Nov 27 '23 at 18:16
  • PM 2Ring: Shell theorem, got it, I'll look into that, Thanks.

    Otherwise, I feel like it's in mainstream physics? I'm only talking about gravity. From the post mentioned, this seems to fit the best: "a question that proposes a new concept or paradigm, but asks for evaluation of that concept within the framework of current (mainstream) physics is OK"?

    – MGamsby Nov 27 '23 at 18:21
  • Although your scenario involving black holes is not likely, the effects of other nonuniformities in mass distribution might not be so far fetched. In a universe with regular patterns of concentrations and voids, the expansion will seem to be faster when viewed from the voids and slower when viewed from the concentrations. This effect is not currently believed to be large enough to explain away dark energy however. – D. Halsey Nov 28 '23 at 15:04
  • @D.Halsey : I appreciate your input! Can I ask you to elaborate on why you believe black holes are unlikely? From my perspective, we still have a lot to learn about the universe beyond what we can observe, so I'm curious to understand your perspective on this. Very distant black holes would also be very old, much more than the short span of 13,8 billions years – MGamsby Nov 29 '23 at 02:10

2 Answers2

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Dark Energy is an unfortunate name, as it goads ppl into finding missing energy. We already have that problem with Dark Matter.

The EFE can be written:

$$ G_{\mu\nu} = kT_{\mu\nu} - \Lambda g_{\mu\nu} $$

So for $\Lambda=0$, we have the usual matter ($T_{\mu\nu}$) tells spacetime how to curve ($G_{\mu\nu}$).

With a non-zero cosmological constant, there is a "correction" to the stress energy tensor that is proportional to the metric.

If you consider a lone mass at rest, the contribution to curvature from matter is $T_{00} \propto m$...which looks like Newtonian gravity.

Meanwhile, even in fast spacetime, the cosmological constant contributes $-\eta_{\mu\nu}=-{\rm drag}(1, -1,-1,-1)$, which is completely different from stress-energy.

JEB
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  • Thank you for your answer. I'm sorry if what I'll say is not true (not a physicist), but I thought that the cosmological constant was still not agreed upon, in part due to the "cosmological constant problem"? – MGamsby Nov 27 '23 at 20:20
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A spherically symmetric shell of matter exerts precisely zero gravitational force on anything inside the shell. This is Newton's shell theorem.

So no, this idea doesn't work for at least one important reason.

ProfRob
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  • PM 2Ring mentioned the shell theorem too, but I don't think it's (directly) relevant here?

    Since there's no shell? There's the big bang in the "center", and there's multiple objects around it. I guess the point is that it would act as a sphere around, but that's not it.

    Actually, if we take the shell theorem, with infinite black holes, on bigger scale, we would need to use the corollary that inside a solid sphere of constant density (which is closer to what I'm describing to a hollow sphere), the gravitational force within the object varies linearly with distance from the center.

    – MGamsby Nov 29 '23 at 01:16
  • @MGamsby "Suppose the universe from our big bang is surrounded by some distant mass...". This and the subsequent text in your question describe a shell around our universe. Please revise your question to say what you mean. – ProfRob Nov 29 '23 at 01:26
  • Alright, I thought this was describing it, I see now that it's not quite descriptive enough, I'll revisit what I had("In the grand scheme of things, there would be an infinite (or very large) collection of BBMBHs."), thanks for the input. – MGamsby Nov 29 '23 at 01:34
  • Actually I retract that the corollary describes it, but I still don't think the shell theorem does either. I added some explanations and some visual representations to try and clarify all of that ambiguity around the shell theorem. I also updated the question. – MGamsby Nov 29 '23 at 14:35