Thursday, June 4, 2009

Black Holes versus Big Bang

The Schwartzchild radius for a mass equal to the entire universe is, I estimate without calculation, larger than one metre.

If the Big Bang theory is true, then the entire universe was once inside its own Schwartzchild radius.

Inside the Schwartzchild radius, colliding with the singularity within finite proper time is inevitable.

The universe is not a singularity.

Conclusion:

Big Bang theory is false.

OR

Black holes do not exist.

QED.

Obviously, objects very similar to black holes exist, as attested by accretion rings and gravitational lenses. The Big Bang may be allowed to be singular because the first event is in many ways special - as long as after any finite time, it is no longer singular, everything is fine.

Ergo, most likely, black holes do not exist. When our physics tells us there is a singularity in nature, we're wrong.

6 comments:

Anonymous said...

Why are you throwing out black holes instead of the big bang theory? The big bang has become obsolete since hot inflation was developed.

Basically you're throwing out the object for which there is good empirical and theoretical evidence, and siding with an obsolete theory.

Alrenous said...

The point of the article is that the beginning of the universe is projected to be essentially a point, but this idea contradicts GR.

I'm sorry I wasn't clear, but as far as I'm concerned inflation is an optional feature of the Big Bang family of ideas. You turn it on and off as the evidence dictates.

Mitchell said...

Both Big Bang and black holes are modelled using general relativity, a theory whose predictions are determined exactly and mathematically, rather than qualitatively and analogically.

Professional astrophysicists and cosmologists do not deduce that the Big Bang universe should have swiftly become a black hole.

Alrenous does.

Conclusion:

The professionals are getting the maths wrong.

OR

Alrenous has made an error in his qualitative reasoning.

QED

Mathematically, a big-bang universe is usually described by a Robertson-Walker metric, a black hole by a Schwarzschild metric. So the question is, why is it that a Robertson-Walker universe doesn't immediately turn into one big Schwarzschild object, and yet little Schwarzschild regions still manage to form later on, against the persisting Robertson-Walker background.

The fact I can't answer this question immediately says I need to do some remedial G.R. But Wikipedia alleges that the universe didn't turn into one big black hole from the beginning because of the phenomenal homogeneity of the mass distribution. It's as if everything was held together in fantastically strong and smooth gravitational tension, and it was only as things thinned out that you had localized gravitational asymmetry strong enough to break the tension and cause localized collapses.

Discussions you may find stimulating: 1 2 (role of energy and pressure terms).

Alrenous said...

Wikipedia's allegation would indeed solve the problem. Except, it assumes a particular shape of universe - that of the video-game wrapping kind. This would result in a hall of mirrors effect, which has been proposed before.

However, it has no experimental support that I know of. The universe is still considered to be infinite by most, and you can't have both.

Basically I haven't seen it show up again, which usually means the idea tripped over itself and died, more's the pity, as it would quickly solve the horizon problem. Instead, experimental evidence that seems pretty much the opposite of a hall of mirrors has been found.

It is known that an exact solution to the Big Bang would require a fusion of QM and GR, which does not exist.

The professionals are getting the maths wrong.

OR

Alrenous has made an error in his qualitative reasoning.

QED


You thought my formatting was so nice you copied it. I'm flattered.

I don't see the need to just state the dichotomy of "I'm right OR I'm wrong," though.

I'd certainly hope that astrophysicists and cosmologists solve their models mathematically. However, I wouldn't expect them to notice when their assumptions don't make any sense, precisely because you often need qualitative reasoning to be able to do that. Usually, the only thing that will cop a physicists to bad assumptions is an infinity, and in BB's case, we expect to find an infinity or two anyway. So. (Or experimental falsification, which doesn't apply here.)

I'm hard pressed to accept any metric of the Big Bang since we know that it requires both QM and GR, which we can't currently do.

I'm now going to read 1 and 2 and I may return if they have anything to add.

Mitchell said...

I'm actually making a point that doesn't involve quantum gravity, physical infinities, or anything so recondite. It's just that your original syllogism is technically invalid at the level of non-quantum general relativity, and not just for a spatially closed universe. In the standard Big Bang model, if space stretches off to infinity, so does the dense primordial plenum, and so does this balanced-tension effect which prevents local gravitational collapse from occurring until expansion has thinned things out a lot.

I'm all for the attempt to deductively find contradictions in physics, but this particular argument doesn't work. Maybe the essence of it is as follows: an event horizon will not form around a dense concentration of matter, if the space all the way out to the Schwarzschild radius is equally densely packed. It's a feature of the Big Bang model that space starts out packed with matter everywhere, in the form of a plasma of elementary particles which only move an infinitesimal distance before colliding with another. It's only when the expansion of space has increased that mean free path between collisions substantially that you begin to have isolated enough concentrations of matter for mini black holes to form - that's the intuitive explanation I've picked up from my brief search for an answer.

Alrenous said...

an event horizon will not form around a dense concentration of matter, if the space all the way out to the Schwarzschild radius is equally densely packed.

Yes, as essentially there'd be no curvature. Actually this gives me some ideas about dark matter as well, as there could be an absurd amount of it but if there isn't any density variation it would be undetectable.

And yes, I did find 1 and 2 stimulating.