[Vern (OP)]

I never thought of this before but I just recently realized that the early universe was a black hole. Does anyone know the mainstream view of how the universe emerged from its primordial black hole?

[Vern (OP)]

No takers? I guess no one is confident that they understand this. How about some guesses? My guess is that it is somehow explained by the great expansion phenomenon.

[Don_1]

I have long thought that the universe is cyclic. All matter is swallowed into a series of black holes which eventually combine, or smaller black holes are consumed by larger ones, until there is just one (although it would be possible for there to be more) super sized black hole. It would be fair to guess that this black hole could be the size of an apple, the size of the Milky Way or anything in between.

When this black hole reaches a finite mass/density, individual atoms cease to exist. The fusing of the atoms creates a nuclear chain reaction which the gravitational force of the black hole contains until the point of explosion of cataclysmic proportions which rips the black hole apart, sending newly restructured atoms , some in huge mixed atomic chunks, some as subatomic particles in all directions to reform the universe. The beginning of the end of this universe would be the formation of the first new black hole.

[Vern (OP)]

I haven't seen that concept before. I guess one unknown mechanism is as good as any other unknown mechanism. []

[Don_1]

Let's face it, we will never know the truth, since we wont live through the death/re-birth of the universe, and we can only 'best guess' at how this universe began. As you say 'one unknown mechanism is as good as any other unknown mechanism.'

[Vern (OP)]

I was hoping to get some discussion about how we avoid this seeming paradox. The early universe was a black hole. Yet; we don't seem to be inside a black hole now. I find many explanations on the net, but there is no peer-reviewed mainstream scientific view. Guth did not seem to mention it. Hawking did not mention it, that I can find.

It is not a problem for me because I dismissed the Big Bang scenario long ago. But I wonder what invention the advocates have produced to reconcile this problem. 

[Ethos]

Whether Black Holes are truly black or not, we have observed massive bodies at the center of Galaxies including our own Milky Way. Along with this compaction of matter taking place, we also observe the expansion of space over the last 13.7 billion years. It's pretty evident to me that both expansion and contraction are happening simutaneously, and this process may in fact, be evidence for the Steady State model.

If there exists a physical limit for the amount of mass that can occupy a local frame, that would explain the evolution of this process. Imagine for a moment that the event we have named the Big Bang was only local to our portion of an infinite space. If the Universe is infinite in scope and eternal, then similar events would have occured an infinite number of times in the past. This would result in the largely homogeneous Cosmic Backgound we presently observe.

The Big Bang is not positive proof that there was a beginning, it may only be evidence for a local event in a truly infinite Space.

.....................Ethos

[Vern (OP)]

I suspect that Black Holes are not truly black. I can think of several limiting factors. One is gravity itself. As gravity increases, time slows. As time slows, acceleration slows. If we consider all of the phenomena of relativity, it is impossible to model the formation of a black hole from an accretion disk. It is easy to say a super massive star collapses into a black hole. But it is impossible to model a realistic episode of this when you consider relativity phenomena.

We know that relativity phenomena is real. We don't know that Black Holes are real. I suspect that there is a physical limit for the amount of mass that can occupy a local frame. It will be related to Planck's constant and gravity, but I can't guess the exact relationship. I have suspected for a while that as gravity increases the measured value of Planck's constant decreases. It might be possible to devise a test of this.

[Soul Surfer]

Go to my area on "evolutionary cosmology" in the new theories pages or my website for some more detailed thoughts on this idea.

http://www.thenakedscientists.com/forum/index.php?topic=11668.0

 

[Don_1]

Ethos, I quite agree with you that any 'big bang' could have been localised and that expansion/contraction happen simultaneously. In my idea of a 'cyclic' universe, there could be any number of black holes forming and reaching the point of finite density/mass at which they would explode. These 'big bangs' do not need to happen simultaneously, and matter from one big bang can result in the formation of another black hole along with matter from several other instances. Its a sort of a cross between the steady state and big bang theory's.

[DoctorBeaver]

Ethos - that's a very interesting hypothesis. I too have often thought that there may be a limit to the mass that can be contained inside a BH, although I haven't really followed that thought through to any great extent.

Saying that everything in our universe (our visible universe) originated from the/a Big Bang seems to be correct insofar as our observations allow. However, if you take "universe" to mean everything that exists everywhere then there is no way we can know. We assume homogeneity, but that's all it is - an assumption.

If Big Bangs are localised events then each could form a domain unobservable from other domains due to the distances involved.

[LeeE]

I never thought of this before but I just recently realized that the early universe was a black hole. Does anyone know the mainstream view of how the universe emerged from its primordial black hole?

Hmm...  How early do you mean by 'the early universe?

You can't have a black hole without matter, and matter wasn't formed until relatively late in the BB; until that point it seems that there was only energy.

It also seems that most of the matter created during the BB was subsequently annihilated by the nearly identical amount of anti-matter that was also created, so I doubt that the density of the matter that was left would have ever been high enough for a BH to form.

It seems that it was only after gravity had been able to accumulate enough matter, in relatively small spaces, that stars could have formed, and then only by their collapse that BHs could occur.

As for starting with a BH; the idea that there might be an upper limit for the size of Black Holes is attractive and would seem to offer some easy solutions but there just doesn't seem to be any proof or mechanism (reason) for it.  Even if the universe started with the mutual annihilation of a matter BH and an anti-matter BH it would still seem that the release of energy would be constrained within the event horizon and apart from the change in mass (both matter and anti-matter seem to have positive mass) the BH must appear unchanged, even though the matter forming it no longer exists (Actually, I think this is only a problem for BH models where matter and energy are posited to exist within the EH in the same form as exists outside the EH).

[Vern (OP)]

Wouldn't energy density equate to matter density? All the mass and energy that I know about both generate and are affected by gravity.

[LeeE]

Wouldn't energy density equate to matter density?

Not at the same rate - I think there's a factor of about c^2 between them []

[Vern (OP)]

Ok so I have an amount of energy that will make an earth sized chunk of matter. Wouldn't this amount of energy generate the same amount of gravity as the earth sized chunk?

[syhprum]

I believe it would.

[thelastman]

Here's my opinion:

The Pre-existence reached a critical point and it's trajectory through it gave rise to our Universe.  Image a vase pushed across a table top.  Nothing (qualitatively) happens as it's pushed across the table.  However, when it reaches the critical point that is the edge of the table, only a slight push causes it's state to qualitatively change (it starts falling down to the floor).  Now imagine a glass of water in which the temperature is gradually reduced.  Again, nothing (qualitatively) happens as the temperature drops until we reach the critical point of freezing.  Then only a slight further reduction causes the entire glass of water to freeze over.  Critical points are all around us and they hint of a Universal origin.  Other examples include the failing of a bridge where only a single (critical) bolt which if fails, causes the entire bridge to collapse; a pond of perch which if at the critical point of some predator-prey dynamics, and a single fish is removed, causes the entire population of perch to collapse; nations when if one final affront is committed causes a war.  In all of these examples, the system begins at some stable state, is pushed to a critical point, then suddenly and often catastrophically trajects to some new stable state. 

     Now imagine a superverse and it's myriad dynamic states it could have.  It's not inconceivable that within all the possible dynamics of this system, there exists  critical points which if the system is pushed close to one of them, then only a very slight nudge will cause a sudden, catastrophic, and qualitatively different state to emerge:  The Pre-existence was pushed to one of it's critical points causing a sudden and catastrophic change we call the Big Bang.  The entire history of our Universe is that trajectory from one of those critical point to some final stable state the Pre-existence is trajecting to.

     I think there is a way to access this pre-existence by borrowing a term from Complex Analyis:  Analytic Continuation.  Those familiar with the term will understand the analogy I make with the superverse being the zeta function, and our universe being the Euler sum which the zeta function reduces down to when the critical point of Re(z)>1 is reached.

This is how I believe the Universe was created and how I believe we will one day access what came before it.

[LeeE]

Ok so I have an amount of energy that will make an earth sized chunk of matter. Wouldn't this amount of energy generate the same amount of gravity as the earth sized chunk?

Hmm...  you need to qualify what you mean by the same 'amount'.  Gravitational 'strength' is governed by density so a star with > 1.4 solar masses does not become a BH just because it has > 1.4 solar masses; the mass needs to be constrained within a specific volume.

If we look back at the very early stages of the BB then it would seem that there should be sufficient equivalent mass within a small enough volume to initiate a collapse, but then there was no space outside the volume for the collapse to have any meaning.  In that sense, the universe does qualify as a BH, as nothing within the universe can seem to leave it.

I once suggested in an earlier thread that our four-dimensional universe might be a four-dimensional BH within a five-dimensional environment, the BB representing the formation of the four-dimensional BH within the five-dimensional super-universe.  In this model though, the BHs we see in our four-dimensional universe can only contain three-dimensional environments within them i.e. one time dimension, but just two spatial dimensions.

[Vern (OP)]

Ok; given the assumptions we must make to even consider the big bang, we can easily also assume that the event was so violent that even a gravitational singularity couldn't keep it from expanding faster than a black hole could form. Then if we accept that the expansion was faster than the speed of light, we can just say that gravity was still limited to the speed of light. Matter then escapes faster than gravity can catch up.

To me it is like religion; there's no way to prove it; there's no way to disprove it.

Edit: No that wouldn't work; if the expansion was faster than gravity, the outer reaches would still be waiting for gravity.

 

[DoctorBeaver]

Edit: No that wouldn't work; if the expansion was faster than gravity, the outer reaches would still be waiting for gravity.

Why do you consider that not possible?