Debate: Do black holes exist?

No, that cannot be right. There isn't a frame outside of the event horizon that can watch B fall past it.

To the extent that the Lorentz transform describes reality, mass would be moving at c at the event horizon cross-over point. If you want to make the case that Lorentz transforms do not adequately describe reality around black holes that's OK but it seems like a kludge that should be corrected if possible. That is the point of my OP.

This is admittedly the weak point of my proposition. I cannot tell you what B would experience, but I'm not suggesting that it would be different than what A calculated. I seem to recall reading once that even the benign photons of the Cosmic Background Radiation would become devastatingly energetic as mass is sufficiently accelerated relative to it; maybe something like this accounts for the proposed destruction of B's rocket ship?

 

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Believe what you will.
Once you see the papers, you'll be rocking back and forth in the fetal position for weeks on end.

 

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In other words you haven't got any evidence.

 

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WIP you fool.
You can look at what's been done.
Grand Unified Theory.
I've done much much more.

 

Prove it.

Prove to me, with some calculation, that the velocity is c. I'm not saying that this isn't true (I can't remember), but if you say it, then surely you must be able to prove it quantitatively.

The point is that you are inventing something to happen at the event horizon, which somehow distinguishes what happens there with what happens in some flat space reference frame. The means that the horizon is a preferred place in the universe, and things there are somehow different from other flat space. This violates the first postulate of special relativity.

 

Right.

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Crank.

 

How could you watch B fall past the event horizon when no light/information of his being in the horizon could possible reach you.

Two possibilities:
He would never reach or end up on the event horizon from A's perspective. To A, it would appear that B is slowing down due to the compaction of space in the area, and eventually he'll stop. His image forever there for A to see.
Or B is ripped apart and spread like butter over the event horizon.

Both events conserve information.

I heard/read about these patterns of events somewhere.

-edit-

Lol.
Didn't even look into it?
If you did, you would have been thoroughly intrigued at the least.

 

Accelerative forces "a" at a distance Schwarzschild coordinate "R" above a black hole of Schwarzschild radius "R_s"...

\(a = \frac{GM}{R^2 \sqrt{1 - \frac{R_s}{R}}}\)

If...
M = 1 solar mass = 1.989E30 kg
R_s = 2,951 m
R = 3,000,000 m
G = 6.674E-11 N(m/kg)^2
Then...
a = 1.475E7 m/s^2

If...
R = 3,000 m
Then...
a = 1.15E14 m/s^2

If...
R = 2960 m
Then...
a = 2.747E14 m/s^2

If...
R = 2951.0001 m
Then...
a = 8.280E16 m/s^2

If...
R = 2951.00000000001 m
Then...
a = 2.618E20 m/s^2

As R approaches R_s, a moves to infinity. What does this mean? It means that we are bumping up against Relativity's insistence that mass cannot be accelerated to c.

But qualitatively think of it in terms of a rocket ship hovering above the event horizon, trying to maintain it's distance. By definition of the event horizon when R = R_s the rocket ship must be moving at c. The fact that Relativity does not allow this should be a powerful argument AGAINST the existence of black holes. The fact that some are comfortable with this incompatibility, I suspect, is because they are "used to it" and have not applied enough critical thought to the subject.

 

Oh yeah, I forgot this trivial proof. The event horizon, by definition, is the point at which light cannot escape the black hole. This is a good example of you neglecting to apply common sense to what you've learned. "Chasing" the rocket ship would not matter. Hovering in a "near by reference frame a few light years away" would not matter either.

 

You can't use F = ma in a relativistic context. Your argument is simply invalid.

?

You really don't know what you're talking about. The only frame which sees B slow down and stop at the horizon is the frame at infinity. All other frames see B fall into the black hole in finite time. This really is a common misunderstanding from people who don't understand the physics. I was actually a bit uncertain on the whole thing myself, until someone convinced me (read: a famous person who's spent his life thinking about black holes) that it was true. You can either believe me or not.

 

Err, what? You asked for calculations, I provided them. I spent quite a while providing them too, with the TEX, etc. And your response is to wave your hand with "F<>ma, therefore invalid". Please provide the appropriate formula for calculating accelerative forces arbitrarily near the event horizon of a black hole. If you do not provide this then my claim is that this is either intellectual dishonesty or a weak mind at work.

Wow bro, I know I'm convinced! You demand calculations, replying with "prove it" THREE TIMES, which I attempted to. Your final reply is "well, this one guy said it works this other way so believe me or don't"...Jesus

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You can't see them fall into the hole...
The horizon itself moves at c. GR says relative speeds are unambiguous locally, and the light is redshifted and takes longer to reach observer A. B becomes dimmer to A as he approaches the event horizon.
You never see him fall in.

 

NOOOO HandyMan, he knows this guy! You can either believe him or don't.

 

RJ Beery: You disagree with my thoughts (Post 13) on Event Horizon growth due to in falling matter. Consider some actual calculations relating to a hypothetical Black Hole with some mass falling toward it.

The Wolfram Alpha site provides a simple equation for the Radius of a Black Hole Event Horizon.

http://www.wolframalpha.com/entities/calculators/black_hole_event_horizon_radius/e3/xp/cm/

The equation indicates that the radius is a linear function of Mass. It results in the following.

• One Solar mass Black Hole: Event Horizon Radius is about 3 Kilometers.
  
  
• Two Solar mass Black Hole: Radius is about 6 kilometers.
  
  
• SolarMass/1000: Radius is about 3 meters.

Now suppose that 1000 small Black holes (Radius 3 meters: Mass =Solar Mass/1000) surround the Black Hole in a spherically symmetric arrangement about 5 kilometers from the Event Horizon & are falling toward the Event Horizon.

What happens when the 1000 small /Black Holes fall to positions slightly less than 3 Kilometers from the Event horizon?

I claim that the result will be a Black Hole with a 6 Kilometer Event Horizon Radius.

The in-falling Solar mass is inside the Event Horizon without having reached the original Horizon (3 kilometer radius).

A distant observer might never see matter reaching an Event Horizon, but (as as per my Post 13) he can observe a Black Hole growing due to in-falling matter.

 

My posts 13 & 34 refute the notion that Black Holes cannot exist. They can exist & they can be observed to grow as matter falls toward them.

 

This is literally the first link I came across using google: http://users.telenet.be/vdmoortel/dirk/Physics/Acceleration.html

You attempted to, and failed. Miserably.

The difference between me and you is that I am self-aware enough to know when I am ignorant, and am humble enough to ask someone who knows to explain it to me. This is the difference between people who are physicists, and people who are armchair physicists. So, if someone who has literally spent his life thinking about black holes tells me something, I listen.

And, you've not proved that there the only frame in which B crosses the horizon is co-moving with B. You've only dismissed my objections out of hand.

 

The title of that page is "SR treatment of arbitrarily accelerated motion," Ben. That should give a clue that it is inappropriate in the vicinity of a black hole.

RJ is very much correct in that an external observer (well, an external beyond 1.5 Schwarzschild radii) will never see something fall into a black hole. RJ is very much incorrect to infer that this means black holes do not exist.

The reason an external observer cannot see an object fall into a black hole is because the time it takes for light to crawl its way back out of the hole grows to infinity as the object approaches the event horizon. The proper time to the object crossing the event horizon is however finite.

Assuming for the sake of argument that RJ was correct about an object never truly falling into a black hole, so what? All he would be doing in this case is quibbling with terminology. Just to reiterate, RJ is not correct about an object not being able to fall into a black hole.

 

Dinosaur, I agree it's an interesting mental exercise but, again, you are presuming that BH's exist in order to analyze this. I have highlighted the word in your statement that is the crux of the problem (in my opinion). It is the WHEN that is in question. If WHEN is t=infinity then this is equivalent to saying that it does not happen.

Your link to Wolfram is basically what I calculated a few posts up. If you read this you can see another one of my objections (i.e. infinite accelerative forces).

Something to keep in mind: what I am suggesting is basically unfalsifiable. From outside of the BH, things would look the same regardless of what was going on "inside".

 

Ah but you appear to be granting an SR exemption to BH's in the same way that Dinosaur did. Einstein claimed that what we SEE is the ultimate arbiter of time progression. Light is what we use for clock synchronization, etc. If B were to hover arbitrarily close to the event horizon, appearing to slow to a crawl, and remain for many years, then return to the distant observer A we would find that he DID IN FACT experience a massive slowing of time. It is not an illusion. Why then are we trying write off the impossibility of an actual crossing of the event horizon as an illusion to be ignored?

Yes, as I said this is all academic but it may not be unfalsifiable as I stated earlier...

As cosmictraveler pointed out to me, Dr. Vachaspati had the same questions that I do.

 

So why are you talking about it in one of the science forums? We have a philosophy forum where people can debate about things such as the number of angels who can dance on a pin.