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Author Topic:   Black Hole Universe Model Questions
New Cat's Eye
Member
Posts: 11665
From: near St. Louis
Joined: 01-27-2005
Member Rating: 2.5


Message 16 of 69 (664764)
06-05-2012 12:27 AM


Bumpdate
That's a bump/update...

This article is on topic:

http://phys.org/...ack-hole-universe-physicist-solution.html

quote:
Our universe may exist inside a black hole. This may sound strange, but it could actually be the best explanation of how the universe began, and what we observe today. It's a theory that has been explored over the past few decades by a small group of physicists including myself.

I ain't got the time right now to get into this, but want it to be on record for future reference.


Replies to this message:
 Message 17 by Echetos, posted 07-10-2012 10:15 PM New Cat's Eye has acknowledged this reply

  
Echetos
Junior Member (Idle past 1708 days)
Posts: 13
Joined: 04-01-2012


Message 17 of 69 (667653)
07-10-2012 10:15 PM
Reply to: Message 16 by New Cat's Eye
06-05-2012 12:27 AM


Re: Bumpdate
Interesting article. Thanks for the bumpdate and course correction.

@DrAdequate:

What I mean by saying the universe is expanding toward a singularity is basically that the Big Bang and the so-called Big Crunch are the exact same thing. The image I used to describe this in the original blog post was an apple.

The skin of the apple represents spacetime. The core of the apple represents a singularity out of which the universe--you, me, all the stars and galaxies--emerged. One can imagine a galaxy, sometime after the Big Bang, moving out and away from this singularity according to Hubble's law, eventually crossing the "equator" of the apple/universe, and finally winding up right where it started.

Of course this is just a visual aid and implies nothing about the actual shape or structure of the universe. For a more detailed explanation please see the original blog post here:

http://scottsteffens.blogspot.com/2012/04/bhum-bee-hum.html

Ultimately, the BHUM claims the universe--specifically the multiverse--is one gigantic black-sive-white hole.


This message is a reply to:
 Message 16 by New Cat's Eye, posted 06-05-2012 12:27 AM New Cat's Eye has acknowledged this reply

Replies to this message:
 Message 18 by Dr Adequate, posted 07-10-2012 11:30 PM Echetos has responded

    
Dr Adequate
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Posts: 15948
Joined: 07-20-2006
Member Rating: 5.0


Message 18 of 69 (667659)
07-10-2012 11:30 PM
Reply to: Message 17 by Echetos
07-10-2012 10:15 PM


Re: Bumpdate
What I mean by saying the universe is expanding toward a singularity is basically that the Big Bang and the so-called Big Crunch are the exact same thing. The image I used to describe this in the original blog post was an apple.

The skin of the apple represents spacetime. The core of the apple represents a singularity out of which the universe--you, me, all the stars and galaxies--emerged. One can imagine a galaxy, sometime after the Big Bang, moving out and away from this singularity according to Hubble's law, eventually crossing the "equator" of the apple/universe, and finally winding up right where it started.

In which case when it crossed the equator it would be contracting towards a singularity. You see why I was puzzled?


This message is a reply to:
 Message 17 by Echetos, posted 07-10-2012 10:15 PM Echetos has responded

Replies to this message:
 Message 19 by Echetos, posted 07-11-2012 6:06 PM Dr Adequate has responded

  
Echetos
Junior Member (Idle past 1708 days)
Posts: 13
Joined: 04-01-2012


Message 19 of 69 (667745)
07-11-2012 6:06 PM
Reply to: Message 18 by Dr Adequate
07-10-2012 11:30 PM


Re: Bumpdate
It's puzzling because 4-dimensional objects are puzzling. But I must insist that this is an expansion, or at least looks like one. From the perspective of an observer anywhere on this apple/universe all the galaxies, everything, will appear to be moving away at an accelerated rate in all directions. And thus the observer is left to conclude the universe is expanding, which it is, toward a singularity.
This message is a reply to:
 Message 18 by Dr Adequate, posted 07-10-2012 11:30 PM Dr Adequate has responded

Replies to this message:
 Message 20 by Dr Adequate, posted 07-11-2012 6:52 PM Echetos has not yet responded
 Message 21 by New Cat's Eye, posted 07-12-2012 9:53 AM Echetos has responded

    
Dr Adequate
Member
Posts: 15948
Joined: 07-20-2006
Member Rating: 5.0


Message 20 of 69 (667748)
07-11-2012 6:52 PM
Reply to: Message 19 by Echetos
07-11-2012 6:06 PM


Re: Bumpdate
It's puzzling because 4-dimensional objects are puzzling. But I must insist that this is an expansion, or at least looks like one. From the perspective of an observer anywhere on this apple/universe all the galaxies, everything, will appear to be moving away at an accelerated rate in all directions.

Not after the "equator" has been passed. Then it'll look like it's contracting. 'Cos it'll be contracting.


This message is a reply to:
 Message 19 by Echetos, posted 07-11-2012 6:06 PM Echetos has not yet responded

  
New Cat's Eye
Member
Posts: 11665
From: near St. Louis
Joined: 01-27-2005
Member Rating: 2.5


Message 21 of 69 (667789)
07-12-2012 9:53 AM
Reply to: Message 19 by Echetos
07-11-2012 6:06 PM


Re: Bumpdate
If it doesn't stop expanding and start contracting, then it'll look like a horn instead of a sphere or apple:


This message is a reply to:
 Message 19 by Echetos, posted 07-11-2012 6:06 PM Echetos has responded

Replies to this message:
 Message 22 by Echetos, posted 07-12-2012 5:56 PM New Cat's Eye has responded

  
Echetos
Junior Member (Idle past 1708 days)
Posts: 13
Joined: 04-01-2012


Message 22 of 69 (667851)
07-12-2012 5:56 PM
Reply to: Message 21 by New Cat's Eye
07-12-2012 9:53 AM


Re: Bumpdate
@Dr Adequate

I think we might be veering off into a fruitless semantic argument.

@Catholic Scientist

I said in the original blog post that the universe is expanding and contracting at the same time. However, from the perspective of an observer at any point the universe will appear to be expanding at an accelerated rate in all directions (according to Hubble’s law).

And as for discussing the shape of a hypothetical 4-dimensional object, I think the horn image helps.

Wish I could figure out how to paste this image in here but here's a link:

http://1.bp.blogspot.com/...w/SkC0D2Q9zKs/s1600/Diagram3.bmp

I guess the main point—if we can bracket the shape issue for a moment—is the fact that the empirical evidence suggests the universe is expanding toward a singularity. Hubble’s law states that double the distance and the galaxies are moving away twice as fast. This is exactly what one would expect (and can easily observe) of objects falling toward a singularity. The example I used in the blog post was tossing pennies off of a tall building. Drop three pennies in 5 second intervals and the first penny will always be moving faster than the second, and the second than the third, because of the acceleration due to gravity. The observer—the person dropping the pennies—might conclude that space is moving away from him (expanding), or, he might conclude that the pennies (i.e. red-shifted galaxies) are falling toward a gravitational singularity. Which they are, of course: the center of the earth.


This message is a reply to:
 Message 21 by New Cat's Eye, posted 07-12-2012 9:53 AM New Cat's Eye has responded

Replies to this message:
 Message 23 by NoNukes, posted 07-13-2012 9:15 AM Echetos has responded
 Message 25 by Dr Adequate, posted 07-15-2012 12:45 AM Echetos has responded
 Message 38 by New Cat's Eye, posted 07-17-2012 11:14 AM Echetos has responded

    
NoNukes
Inactive Member


Message 23 of 69 (667892)
07-13-2012 9:15 AM
Reply to: Message 22 by Echetos
07-12-2012 5:56 PM


Re: Bumpdate
Hubble’s law states that double the distance and the galaxies are moving away twice as fast. This is exactly what one would expect (and can easily observe) of objects falling toward a singularity.

It's also exactly what we would expect if the expansion was per FLRW cosmology, which does not include the universe falling towards a singularity.

I don't think your idea that the universe is expanding and contracting at the same time matches any observational evidence. Is there any evidence that this notion you have is real?

ABE:

Echetos writes:

Which they are, of course: the center of the earth.

You believe there is a singularity at the center of the earth?

Edited by NoNukes, : No reason given.


Under a government which imprisons any unjustly, the true place for a just man is also in prison. Thoreau: Civil Disobedience (1846)

The apathy of the people is enough to make every statue leap from its pedestal and hasten the resurrection of the dead. William Lloyd Garrison


This message is a reply to:
 Message 22 by Echetos, posted 07-12-2012 5:56 PM Echetos has responded

Replies to this message:
 Message 29 by Echetos, posted 07-16-2012 9:25 PM NoNukes has responded

  
jasonlang
Member (Idle past 900 days)
Posts: 51
From: Australia
Joined: 07-14-2005


(3)
Message 24 of 69 (667964)
07-14-2012 1:43 PM
Reply to: Message 8 by New Cat's Eye
05-21-2012 11:43 PM


quote:
I suppose a black hole could exist within the event horizon of another, but I can't imagin a universe like ours being a really big black whole because, well, to be blunt: because they're really fucking dense...
Isn't our universe less dense than a black hole?

The universe is no less dense than a universe-sized black hole would be. It uses the Schwarzchild equation here. "Common Sense" from small blackholes - that they are massively dense, doesn't hold for black holes of truly massive size.

"The Schwarzschild radius is proportional to the mass " (see e.g. wikipedia or any other site about the equation). You can infer all you need to from that one mathematical observation.

Doubling the mass, doubles the radius of the event horizon. When the radius of a sphere doubles, the volume is 8 times as great. This means each time you double the mass of a black hole, density drops by 3/4.

There is an inter-relationship between mass, radius and density. Given any one of these you can calculate the other 2 black hole values.

you can plug the observed density of the known universe in, and get an estimate of the size of event horizon which is not far off the observed distance to the earliest galaxies.

Oh, and btw, a "closed" space would wrap-around, so there's no "point" for the singularity to be, just as we do not observe a "middle" from which the universe expands. A totally curved space doesn't need a "middle".

Edited by jasonlang, : No reason given.

Edited by jasonlang, : No reason given.


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Dr Adequate
Member
Posts: 15948
Joined: 07-20-2006
Member Rating: 5.0


(1)
Message 25 of 69 (667989)
07-15-2012 12:45 AM
Reply to: Message 22 by Echetos
07-12-2012 5:56 PM


Re: Bumpdate
I think we might be veering off into a fruitless semantic argument.

If you're going to use the word "expanding" to mean "contracting", then I'm very much afraid that that's what we shall do.

You could avert this by using "expanding" to mean "expanding" and "contracting" to mean "contracting".


This message is a reply to:
 Message 22 by Echetos, posted 07-12-2012 5:56 PM Echetos has responded

Replies to this message:
 Message 26 by Echetos, posted 07-16-2012 7:42 PM Dr Adequate has responded

  
Echetos
Junior Member (Idle past 1708 days)
Posts: 13
Joined: 04-01-2012


Message 26 of 69 (668050)
07-16-2012 7:42 PM
Reply to: Message 25 by Dr Adequate
07-15-2012 12:45 AM


Re: Bumpdate
@Dr Adequate

I think I’ve made it pretty clear that to any observer—according to the BHUM—the universe will appear to be expanding.

You said:

“Not after the “equator” has been passed. Then it’ll look like it’s contracting.”

So I must ask you: Where would an observer need to be positioned for the universe to “look like it’s contracting”?

Unless you’ve mastered some sort of magical gorilla geometry to match your smugness, I’m afraid it’s mathematically impossible.

Maybe this example will be simpler to understand…

Picture a piece of plain old flat computer paper. The paper is the universe in this analogy! An observer (if it helps pretend you’re the observer) is positioned at the center of said piece of paper. Everything the observer can see—i.e. red shifted galaxies—appears to be moving away from him/her according to Hubble’s Law. From this empirical observation the observer concludes the universe is expanding. Yes, expanding. Hubble’s Law is the reason scientists believe the universe is expanding.

Now picture the edges of said piece of paper. The edges represent the singularity in this analogy. (Wait I though a singularity was a point not a square blah blah blah). You may need to take a piece of computer paper from your printer to see how it can be folded back to resemble a sphere. Yup, space can bend. Fancy that.

I should probably mention again, though I’ve stated this point before in multiple posts, is that we are talking about a hypothetical 4-dimensional object. You can’t picture a 4-dimensional object. Neither can I nor anyone! They don’t make sense. The closest we can get is a Mobius strip or a Klein bottle.

If you had actually read the original blog post this would not have been such a distracting issue.

When I said we were veering off into a fruitless semantic argument I didn’t mean to be an ass. I just meant that we were veering off into a fruitless semantic argument. You could avert this by having less of an ego, and understanding that when I use the word “expanding” I mean just that: expanding.

So I must ask you again, because this is the question you’ll dodge to save face: Where would an observer need to be positioned for the universe to “look like it’s contracting”?

I’ll tell you the answer: The observer’s head needs to be positioned somewhere near Uranus.

@jasonlang

Great information. I wonder if more evidence than this needs to be presented to at least get people to admit there is a possibility that the universe is one gigantic black hole?


This message is a reply to:
 Message 25 by Dr Adequate, posted 07-15-2012 12:45 AM Dr Adequate has responded

Replies to this message:
 Message 27 by Dr Adequate, posted 07-16-2012 7:58 PM Echetos has responded

    
Dr Adequate
Member
Posts: 15948
Joined: 07-20-2006
Member Rating: 5.0


Message 27 of 69 (668052)
07-16-2012 7:58 PM
Reply to: Message 26 by Echetos
07-16-2012 7:42 PM


Re: Bumpdate
* sighs *

In order for there to be a Big Crunch, in order for the universe to end up "finally winding up right where it started", it has to contract. Then we will not observe it expanding. We'll observe it contracting. The stars will appear blue-shifted to an observer. They will be getting closer together.

This is why we know that this isn't happening now.

So I must ask you again, because this is the question you’ll dodge to save face: Where would an observer need to be positioned for the universe to “look like it’s contracting”?

Anywhere inside it, during the phase in which it is in fact contracting.

Edited by Dr Adequate, : No reason given.


This message is a reply to:
 Message 26 by Echetos, posted 07-16-2012 7:42 PM Echetos has responded

Replies to this message:
 Message 28 by Echetos, posted 07-16-2012 8:43 PM Dr Adequate has responded

  
Echetos
Junior Member (Idle past 1708 days)
Posts: 13
Joined: 04-01-2012


Message 28 of 69 (668056)
07-16-2012 8:43 PM
Reply to: Message 27 by Dr Adequate
07-16-2012 7:58 PM


Re: Bumpdate
You can't be inside it. The surface is spacetime.
This message is a reply to:
 Message 27 by Dr Adequate, posted 07-16-2012 7:58 PM Dr Adequate has responded

Replies to this message:
 Message 30 by Dr Adequate, posted 07-16-2012 10:11 PM Echetos has responded

    
Echetos
Junior Member (Idle past 1708 days)
Posts: 13
Joined: 04-01-2012


Message 29 of 69 (668060)
07-16-2012 9:25 PM
Reply to: Message 23 by NoNukes
07-13-2012 9:15 AM


Re: Bumpdate
@NoNukes

A gravitational singularity, yes, at the center of earth. This is gravity 101.

From Einstein’s Universe, Nigel Calder elaborates:

“In Einstein’s theory the main features of gravity around the Earth are exactly the same as they would be if our planet were hollow, with a faked-up papier-mâché surface of mountains and seas, but having a black hole at the centre with the same mass as Earth. [...] The German theorist Karl Schwarzschild offered this very useful interpretation almost immediately after Einstein published his theory.” (74).

Edited by Echetos, : To add @NoNukes


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Dr Adequate
Member
Posts: 15948
Joined: 07-20-2006
Member Rating: 5.0


Message 30 of 69 (668062)
07-16-2012 10:11 PM
Reply to: Message 28 by Echetos
07-16-2012 8:43 PM


Re: Bumpdate
You can't be inside it.

I can, in fact, be in the universe. I am habitually in the universe. It's getting out of it that would be tricky.


This message is a reply to:
 Message 28 by Echetos, posted 07-16-2012 8:43 PM Echetos has responded

Replies to this message:
 Message 32 by Echetos, posted 07-16-2012 10:47 PM Dr Adequate has responded

  
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