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Author Topic:   Black Hole Universe Model Questions
NoNukes
Inactive Member


Message 7 of 69 (663168)
05-21-2012 11:34 PM
Reply to: Message 6 by New Cat's Eye
05-21-2012 11:06 PM


Could you expand on this a bit? I understand cosmology fairly well, and am pretty smart, so feel free to use a bit of jargon and/or math. I'm under the impression that the inside of a black hole would be much different than its surroundings.

It might be easier to picture if you understand "inside of a black hole" to mean within the event horizon of the black hole. I am not aware of any particular reason why black holes could not exist within the event horizon of another black hole.

At any rate, in the case of a stupendously enormous (universe sized???) black hole, there would be no sensation noted when crossing the event horizon. Yes it is true that light cannot escape from the black hole, but if you were really far from the event horizon, and also stupendously far from the singularity I think things could look pretty normal.


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 6 by New Cat's Eye, posted 05-21-2012 11:06 PM New Cat's Eye has responded

Replies to this message:
 Message 8 by New Cat's Eye, posted 05-21-2012 11:43 PM NoNukes has responded

  
NoNukes
Inactive Member


(1)
Message 10 of 69 (663234)
05-22-2012 1:57 PM
Reply to: Message 8 by New Cat's Eye
05-21-2012 11:43 PM


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?

Not forbiddingly dense if you consider the volume of the black hole to be volume enclosed by the event horizon. I think there was some discussion of the math in designtheorist's thread about whether the total energy of the universe was zero.

The way I understand it, things would be a lot different if that was the case, but he seems to be saying otherwise.

Different in what way? I don't see anything in CTH's discussion that requires you to be in the tidal, spaghetiifying vicinity of a singularity. Once you are within the Schwarzschild radius, there is no escape.

I think you are imagining being in the "squeezed matter" portion of the black hole. Yeah, things would be different there.


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 8 by New Cat's Eye, posted 05-21-2012 11:43 PM New Cat's Eye has acknowledged this reply

  
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

  
NoNukes
Inactive Member


(1)
Message 37 of 69 (668106)
07-17-2012 9:07 AM
Reply to: Message 29 by Echetos
07-16-2012 9:25 PM


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

Nope.

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

The above statement is of course true. The gravitational field "around the earth" meaning external to the earth is exactly the same as if the planet were hollow, or compressed to a fraction of its current size.

However, the gravitational field within the earth is not the same as the gravitational field that would be present if the earth were collapsed to a black hole.

Imagine being inside the earth. You would be pulled in different directions by different parts of the earth because the "force" of gravity acts along the line between masses. It is easy to show that the net gravitational field at the center of the earth is zero.

In fact, using Gauss's law, which would be the real gravity 101, we can show that the gravitational field due to a hollow object is zero at any point inside of the hollow object. It does not tend towards infinity.

Similarly, for a solid object, we can show that the gravitational force on an object inside the object decreases as we approach the center, for objects having "reasonable" density profiles at their center. We believe the earth to have iron, and not neutronium, at its center.

If there were a singularity at the center of the earth due to a tiny black hole being present, Gauss's law predicts that we could not detect the black hole at the earth's surface. That's why in my initial post, I merely asked whether you believed there was a singularity within the earth. I did suspect, however, that you were simply applying the inverse square law to the inside of the earth, and that suspicion turned out to be correct.

I would also note that your "falling toward a singularity" analysis is incomplete. You are correct that gravity of singularity causes the distance between two objects lying along the line to the singularity would increase with time due to tidal effects. However there is a second gravitational effect that produces a compression of separations perpendicular to the direction towards a singularity. Yet that compression is not observed. The observed isotropic expansion does not match your proposal.

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 29 by Echetos, posted 07-16-2012 9:25 PM Echetos has not yet responded

  
NoNukes
Inactive Member


Message 43 of 69 (668325)
07-19-2012 9:53 PM
Reply to: Message 39 by Echetos
07-18-2012 10:40 PM


Re: Bumpdate
You can. And you’re right. I didn’t mean to imply there’s a black hole singularity at the earth’s center. It’s my hope, and I assume the case is, that you knew I didn’t mean that.

Okay, I can accept that. By now I hope you understand the problem some of us (me, Jar) have pointed to regarding the falling penny analogy.

But when you talk about the universe contracting towards a singularity, are you referring to an actual singularity in that case?

And I’m the first person to admit that I don’t fully understand the implications of such a model. But I'll defend it tooth and nail because I believe it to be intuitively true.

The above statement is one I simply don't find logical. What would make you defend a model that you don't understand? Or asked another way, why is an intuition about a model whose implications you don't understand, an intuition to be valued?


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 39 by Echetos, posted 07-18-2012 10:40 PM Echetos has not yet responded

  
NoNukes
Inactive Member


Message 46 of 69 (668866)
07-25-2012 8:58 AM
Reply to: Message 45 by Echetos
07-25-2012 3:12 AM


Re: Bumpdate
All reasoning is circular. This circularity belongs even to the most rigorous of traditions, including science, mathematics, and logic. Give me one truth arrived at by noncircular reasoning and you’ve solved a foundational epistemological conundrum—the problem of contemporary philosophy.

Nonsense. Try reading a few chapters of Euclid and see how non circular proofs work.

It is the case that there are some axioms that are accepted as true without proof. But given those, it is certainly possible to derive more things without any circular reasoning.

I responded:

You can't be inside it. The surface is spacetime.

You could not possibly be this obtuse. You have already acknowledged that the universe appears to be expanding to observers within the universe. How can you say that and then follow it up with denying Dr. Adequate a viewing point within the universe?


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 45 by Echetos, posted 07-25-2012 3:12 AM Echetos has not yet responded

  
NoNukes
Inactive Member


Message 55 of 69 (669598)
07-31-2012 11:43 AM
Reply to: Message 54 by foreveryoung
07-31-2012 9:52 AM


Outing flannel???
The reality behind it is matter waves.

Voltaire30, what the heck are matter waves if not something you made up? Are you referring to the deBroglie wavelengths associate with matter? How do you deal with the fact that the wave like nature of large particles is less than that of small particles while the gravity effects are larger for large masses?

Further, static magnetic fields associated with a bar magnet are not propagated by electromagnetic waves. A changing magnetic field can generate a changing electric field which generates a changing magnetic field... ad nauseum.

Seriously, what's the point of claiming spacetime mere math and then making up stuff out of whole cloth to replace GR with nonsense.

Edited by NoNukes, : Change title

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 54 by foreveryoung, posted 07-31-2012 9:52 AM foreveryoung has responded

Replies to this message:
 Message 57 by foreveryoung, posted 07-31-2012 10:01 PM NoNukes has responded

  
NoNukes
Inactive Member


Message 58 of 69 (669644)
07-31-2012 10:52 PM
Reply to: Message 57 by foreveryoung
07-31-2012 10:01 PM


Re: Outing flannel???
You appear to have invented the idea that sun warps "matter waves" to cause the earth and other planets to travel in elliptical orbits around the sun. Perhaps I am wrong and you got the idea from some other source.

I then gave the example of a static field (make it either electric or magnetic) to see if you could come up with an explanation of how such a field could be produced by some "waving". I don't believe you can.

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 57 by foreveryoung, posted 07-31-2012 10:01 PM foreveryoung has not yet responded

  
NoNukes
Inactive Member


Message 63 of 69 (669796)
08-03-2012 12:21 AM
Reply to: Message 61 by Alfred Maddenstein
08-02-2012 11:19 PM


Re: spacetime?
It's just that no absurd explanation satisfies so it cannot last indefinitely.

Satisfies who? Exactly who or what must be satisfied in order for an explanation to be correct. I''m guessing who means, you, Alfred Maddenstein.

Satisfies is a transient verb.


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 61 by Alfred Maddenstein, posted 08-02-2012 11:19 PM Alfred Maddenstein has responded

Replies to this message:
 Message 64 by Alfred Maddenstein, posted 08-03-2012 1:19 AM NoNukes has responded

  
NoNukes
Inactive Member


Message 65 of 69 (669821)
08-03-2012 10:04 AM
Reply to: Message 64 by Alfred Maddenstein
08-03-2012 1:19 AM


Re: spacetime?
I'll be more explicit. Lots of physics can seem counter-intuitive. Some things are counter-intuitive because they operate in apparent contradiction to what we experience everyday. But other things appear counter-intuitive because our intuition is faulty. In either case, the evidence can demonstrate that our intuition is misplaced.

If your goal is to indicate which ideas don't make sense to you, you are doing an adequate job of defining yourself. But if your goal is to show others why they ought to have the same doubts, you are not being so successful. Nobody has any reason to trust your belief that 100 years of physics is wrong regardless of how well it works, particularly when we see you cite every crackpot on the internet. Planets are cooled suns? Please.


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 64 by Alfred Maddenstein, posted 08-03-2012 1:19 AM Alfred Maddenstein has responded

Replies to this message:
 Message 68 by Alfred Maddenstein, posted 08-04-2012 12:41 AM NoNukes has responded

  
NoNukes
Inactive Member


Message 69 of 69 (669860)
08-04-2012 9:25 AM
Reply to: Message 68 by Alfred Maddenstein
08-04-2012 12:41 AM


Re: spacetime?
Well, it's not that intuition or common sense is ever really faulty. It's rather just limited in scope and application

Intuition can fail without any warning that one has exceeded its scope. I'll let you decide whether that is a fault.

I'm not going to continue any further off the topic of this thread. I have you down in the "don't believe that the universe is finite" and "don't believe there are black holes column".


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 68 by Alfred Maddenstein, posted 08-04-2012 12:41 AM Alfred Maddenstein has not yet responded

  
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