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tommac
2008-Dec-11, 04:15 PM
This question is about the direction of the light escaping from a black hole.

If I am in a spaceship close to the EH of a BH and I shine a flashlight at a 45 degree angle to the direction of gravity. the speed of light in the dirction contra-gravity would be 1/2 the speed of light correct?
Since I am very close the the EH. space-time is being sucked in ( in the direciton of gravity ) at speeds very close to the speed of light.

The speed of light perpendicular to the direction of gravity would be at 1/2 the speed of light. However it would also be pulled towards the direction of gravity. Eventually the light would travel back in the direction of the black hole.

Does this mean that Only if I point the flashlight contra to the direction of gravity could the light escape?

Would this mean that there are escape angles that can be calculated by distaces which would be the max angle that light could travel and still escape the black hole?

JohnD
2008-Dec-11, 04:37 PM
If I am in a spaceship close to the EH of a BH and I shine a flashlight at a 45 degree angle to the direction of gravity. the speed of light in the dirction contra-gravity would be 1/2 the speed of light correct?

The speed of light at this point near to a BH, but not perpendicular to its event horizion is - the speed of light!
That's the whole point - light always travels at the speed of light. It will change its frequency and red shift as the BH draws it down; time may slow for it as it gets closer still, but it still travels - at the speed of light!

John

alainprice
2008-Dec-11, 04:51 PM
The surface where light can travel perpendicular to the singularity (even though in theory everything is perpendicular to it) is called the photosphere.

Infinitely close to the EH, light must travel directly away.

tommac
2008-Dec-11, 05:15 PM
The speed of light at this point near to a BH, but not perpendicular to its event horizion is - the speed of light!
That's the whole point - light always travels at the speed of light. It will change its frequency and red shift as the BH draws it down; time may slow for it as it gets closer still, but it still travels - at the speed of light!

John

Let me re-explain.

lets take a 2d grid. with X and Y axis.

If I move along the X axis at the speed of light:
I move 1 light year in the X axis
and
0 light years in the Y axis.

if I now move diagonally at the speed of light for 1 light year.

1 = x^2 + y^2

if my math is correct
you would move .7 light years in the x direction and
.7 ly in the y direction.

Now lets put the BH back into this grid.

The gravity is pulling negatively in the Y direction at very near the speed of light.

so you travel .7 light years in the Y direction but space time has travelled at 1 light year along the Y axis in the opposite direction. This would result in over .3 light year in the negative Y direction or basically the light would be sucked backwards into the black hole.

Now one can say ... well you still have the movement in the X direction that will escape.

This is where the question lies.

Can the movement in the X direction push the photon away from the gravitational source faster than the difference in speed between space-time in the y direction - the photons movement in the y direction.

So lets take point X'Y' a short unit of time after the photon is released.

distance traveled in the Y direction = -.3 units distance travelled in the x direction is = .7 units. Following a curved line around the BH.

I cant figure out the math but I think it would bring it to the point that the x direction is now parallel and contra to gravity.

I dont think that light can escape if pointing at 45 degrees at the EH.

At the EH only light that was shown directly contra to the gravitational force could escape. At any other angle the light would orbit or fall into the BH.

tommac
2008-Dec-11, 05:16 PM
The surface where light can travel perpendicular to the singularity (even though in theory everything is perpendicular to it) is called the photosphere.

Infinitely close to the EH, light must travel directly away.

And there would be angles associated to all of the distances in between I assume.

John Mendenhall
2008-Dec-11, 05:53 PM
And there would be angles associated to all of the distances in between I assume.

Oh boy. Sounds right to me, but I'm not betting on it.

Jeff Root
2008-Dec-11, 08:24 PM
The surface where light can travel perpendicular to the singularity
(even though in theory everything is perpendicular to it) is called
the photosphere.

Infinitely close to the EH, light must travel directly away.
Two very similar names for two very different things:

Photosphere - The bright, visible surface of a star like the Sun.

Photon sphere - The sphere around a black hole in which a photon
theoretically could "orbit" the black hole. It is located at a distance

Light which crosses the photon sphere from outside to inside will
fall into the black hole. Light emitted exactly "horizontally" in the
photon sphere could theoretically "orbit" forever, as long as its path
never deviates either above or below that sphere. If it is angled
slightly upward, it will spiral away from the black hole and escape.
If it is angled slightly downward, it will spiral in.

The photon sphere marks the limit at which light from background
stars would be visible. In other words, a black hole which does not
have luminous matter falling into it would appear to be a perfectly
black circle the diameter of the photon sphere, surrounded by the
distorted, gravitationally-lensed light from background stars.

-- Jeff, in Minneapolis

Jeff Root
2008-Dec-11, 09:00 PM
This question is about the direction of the light escaping from a black hole.

If I am in a spaceship close to the EH of a BH and I shine a flashlight at
a 45 degree angle to the direction of gravity. the speed of light in the
direction contra-gravity would be 1/2 the speed of light correct?
Since I am very close the the EH. space-time is being sucked in
( in the direciton of gravity ) at speeds very close to the speed of light.

The speed of light perpendicular to the direction of gravity would be
at 1/2 the speed of light. However it would also be pulled towards the
direction of gravity. Eventually the light would travel back in the
direction of the black hole.

Does this mean that Only if I point the flashlight contra to the direction
of gravity could the light escape?

Would this mean that there are escape angles that can be calculated
by distaces which would be the max angle that light could travel and
still escape the black hole?
Much of what you say here is correct. Some of it is not.

As JohnD said, the speed of light is always measured locally to be
the same. You in your spacecraft will measure the speed of light
from your flashlight to be c as it leaves the flashlight. An observer
closer to the black hole will measure the speed of light from your
flashlight to be c as it passes him. On the other hand, determining
the speed of the light relative to you when it is not close to you
is a difficult problem when you are in the vicinity of a black hole.
We don't need to measure such speeds in order to answer your

You are exactly right about the angles. At the photon sphere,
located at 1.5 Schwarzschild radii, light traveling the slightest bit
upward will escape the black hole, while light traveling the least
bit downward will fall in. Just above the event horizon, located
at the Schwarzschild radius, only light which is traveling vertically
upward can escape. Light traveling in all other directions falls into
the black hole. The closer to the event horizon, the narrower the
range of angles light can travel in and still escape.

My understanding about spacetime being "sucked in" to the black
hole agrees with yours. I haven't yet read an authoritative source
which explains it to my satisfaction, but it appears that within
3 Schwarzschild radii, spacetime is effectively in "motion". I do not
understand how that can be, or why it should be. I do not know
what that "motion" actually "is". My interpretation is that the
"motion" is zero at 3 R, the location of "the last stable orbit" and
gradually increases as you approach the black hole. At R, the
event horizon, the speed of the "motion" is equal to c, the speed
of light. The speed of the "motion" would continue to increase all
the way down.

The last stable orbit (at 3 R) is the closest that a massive object
could orbit a black hole in a circular orbit without some kind of
propulsion to counter the effect of being "sucked in". I presume
that an object in an elliptical, parabolic, or hyperbolic orbit could
get closer to the event horizon and still escape without propulsion,
but with a loss of speed, lowering the apoapsis.

-- Jeff, in Minneapolis

tommac
2008-Dec-12, 05:22 PM
The way I look at it, and I am sure someone on here will yell at me for having this opinion but it is how I picture it is the following:

when you travel through space say in a spaceship. You compare your speed to everything else around you.

when you are near a BH everything else is falling into the BH, including you. To hover you need to accelerate and move near the speed of light just to avoid getting sucked in. This is similar to a treadmill. From your vantage point you feel like you are moving very quickly relative to everything else in your vicinity.

I think einstein had a thought experiment about an elevator. If you were to put an elevator into space and attach a rocket to it the person in the elevator would feel like he/she is being affected by gravity.

In this case someone in a hovering elevator would not be able to tell if they are being pulled by gravity OR being pushed by a rocket.

.

My understanding about spacetime being "sucked in" to the black
hole agrees with yours. I haven't yet read an authoritative source
which explains it to my satisfaction, but it appears that within
3 Schwarzschild radii, spacetime is effectively in "motion". I do not
understand how that can be, or why it should be. I do not know
what that "motion" actually "is". My interpretation is that the
"motion" is zero at 3 R, the location of "the last stable orbit" and
gradually increases as you approach the black hole. At R, the
event horizon, the speed of the "motion" is equal to c, the speed
of light. The speed of the "motion" would continue to increase all
the way down.

astromark
2008-Dec-13, 11:51 AM
I can not see why this has not thus far been said... If light is escaping from it then it is not a black hole.
Light attempting to transverse the distance from the hart of the black hole to reach my eye would need to exceed C. or the gravity force exerted upon it.
The gravity of that mass must exceed the speed of light or a black hole, it is not.

Hornblower
2008-Dec-13, 01:04 PM
The way I look at it, and I am sure someone on here will yell at me for having this opinion but it is how I picture it is the following:

when you travel through space say in a spaceship. You compare your speed to everything else around you.

when you are near a BH everything else is falling into the BH, including you. To hover you need to accelerate and move near the speed of light just to avoid getting sucked in. This is similar to a treadmill. From your vantage point you feel like you are moving very quickly relative to everything else in your vicinity.In free fall near an event horizon you are approaching the speed of light. To hover you need to decelerate to a standstill. With a rocket holding the spacecraft in place it will be like standing on a planet with superpowered gravity, with unsupported objects whizzing by you nearly at the speed of light.

I think einstein had a thought experiment about an elevator. If you were to put an elevator into space and attach a rocket to it the person in the elevator would feel like he/she is being affected by gravity.

In this case someone in a hovering elevator would not be able to tell if they are being pulled by gravity OR being pushed by a rocket.
Correct. That is part of the familiar principle of equivalence.

JohnD
2008-Dec-13, 11:59 PM
Hang on, some wild statements here.
Photons have no mass. They are NOT being "pulled down by gravity" but following straight paths in a space-time distorted by the mass of the black hole.
Nick-picking, maybe, but let's get it right.

Jeff Root, thanks you for your clear explanation.
Tommac, were you seeking explanation, or suggesting an outcome form your calculation? To an outside observer your torch (flashlight) would appear reddened and dimmed, and if you flashed it, slower, as you approached the EH, as red shift and time dilation made you hover there, for ever as far as the observer could tell.

John

mugaliens
2008-Dec-14, 08:47 AM
Hang on, some wild statements here.
Photons have no mass. They are NOT being "pulled down by gravity" but following straight paths in a space-time distorted by the mass of the black hole.
Nick-picking, maybe, but let's get it right.

Now hang on, there... It's more than nit-picking. You can't say "not A, but B" when A and B are synonomous. While the Newtonia model requires a mass for both objects (Earth and the hammer), the Schwarzschild metric does not - it describes the spacetime around a mass as if it were being experienced by a massless particle. When M>>m for the Newtonian model, as is the case for all man-made objects orbiting the Earth, the result --> Schwarzschild's.

astromark
2008-Dec-14, 09:28 AM
Not A but B when A and B are synonymous ... NO !
I see the distinction between suggesting 'the photon is held by the force of gravity' and, 'the space it is moving through is being distorted by gravity'
Are we talking of the same thing here..? When the mass of the BH is such that it distorts the space near it. Light can only reach C as a velocity. If the gravity is shrinking space faster than C its escape is impossible. Is that clear enough for you ?

Jeff Root
2008-Dec-14, 11:08 AM
I see the distinction between suggesting 'the photon is held by the
force of gravity' and, 'the space it is moving through is being distorted
by gravity'
Are we talking of the same thing here..?
As concepts, a force of attraction and distorted spacetime are
utterly different. In their effects, they might be indistinguishable.
My guess is that the 'distorted spacetime' description given by
relativity theory is more like an analogy of what is happening than
it is a description of what actually is happening. A perfectly
accurate analogy, though. The rules that describe how objects
move in response to concentrations of matter/energy apparently
are identical to the rules of 4-dimensional geometry. I don't know
why they should be the same, but I'm sure it isn't just coincidence.

In any case, Newtonian gravitational force and Einsteinian general
relativity make very nearly indistinguishable predictions over a very
wide range of situations. As far as I'm concerned they are both
'right'.

(But I have no idea how gravitons, virtual or otherwise, could
escape a black hole. It makes no sense!)

-- Jeff, in Minneapolis

mugaliens
2008-Dec-14, 03:03 PM
Are we talking of the same thing here..? When the mass of the BH is such that it distorts the space near it.

A common football distorts space near it, enough to bend light. Any mass does this, not just BHs. BHs just do it to the extent where they're able to bend light right around them in a circle, or worse.

mr obvious
2008-Dec-14, 03:48 PM
Now lets put the BH back into this grid.

The gravity is pulling negatively in the Y direction at very near the speed of light.

so you travel .7 light years in the Y direction but space time has travelled at 1 light year along the Y axis in the opposite direction. This would result in over .3 light year in the negative Y direction or basically the light would be sucked backwards into the black hole.

Now one can say ... well you still have the movement in the X direction that will escape.

This is where the question lies.

Can the movement in the X direction push the photon away from the gravitational source faster than the difference in speed between space-time in the y direction - the photons movement in the y direction.

I'll approach this from a Newtonian perspective.

This is not a good way to think about the problem. That is because you are using a one-year motion (through which the gravitational pullback is not constant) and you are hinting at orbits (looking at lateral motion to 'overcome' the fallback) instead of escape. Escape is energy; orbit is stability (balance of accelerations).

In general, if you shine the light in any direction away from the BH, it will escape. This is because any motion away from the BH's center of mass will decrease the pull, and by the very definition of escape, the energy remaining will be sufficient to overcome the remaining gravitational potential energy. In fact, in classical theory, as long as there is no physical obstruction, the direction doesn't matter at all. I can shoot something through the Earth (assuming no air resistance and a nice tunnel) with initial escape velocity and it'll still escape. This does not work for a BH because classical theory does not work near BH.

astromark
2008-Dec-14, 06:24 PM
You come back at me as if I have said something new or wrong... Not. Nada and no.
A black hole is a area of massive density. Yes light is redirected, bent, pulled, and even incarcerated. Gravity at work in large and strong bites. Maybe my ability to express thoughts is at fault. or. Do you misunderstand deliberately ?
utterly different, No. I see the same force at work in all cases. just different quantities of force. Am I on my own here ? I do not think so...
Yes all matter has gravity.
The BH has so much it prohibits the light photon path.
The light still travels at C. and that is bellow escape velocity.
Is there some thing wrong with that ? Mark.

Jeff Root
2008-Dec-14, 10:23 PM
You come back at me as if I have said something new or wrong...
Me? Or Mugs? Or both?

I'm not at all sure that either Mugs or I disagreed with what you said.
What I said was pretty vague, so I'm surprised if you interpreted it
as disagreement. But then, the comment of yours that I was replying
to was also rather vague, so I wasn't at all sure what your point was.
I was just giving my personal take on the same idea that you appeared
to be writing about: the relationship between Newton's description of
gravity as a force, and Einstein's description of gravity as a distortion
of spacetime. It is astonishing that two such utterly different
descriptions can both describe the same effects so accurately.

-- Jeff, in Minneapolis

mugaliens
2008-Dec-14, 11:05 PM
You come back at me as if I have said something new or wrong... Not. Nada and no.

Sorry, Astromark - I didn't mean to give that impression. I didn't think you said anything wrong. I merely felt that by the way you said it, it left it open for interpretation that it takes a BH to bend light - I know you're aware of that. My bad for blurting it out as I did. I'll try asking a clarifying question, next time.

Am I on my own here ? I do not think so...

Not at all!

WayneFrancis
2008-Dec-15, 05:30 AM
I can not see why this has not thus far been said... If light is escaping from it then it is not a black hole.
Light attempting to transverse the distance from the hart of the black hole to reach my eye would need to exceed C. or the gravity force exerted upon it.
The gravity of that mass must exceed the speed of light or a black hole, it is not.

From my understanding the hypothesized geometry of a black hole wouldn't even let something that could travel faster then C to escape it. Just like nothing actually every passes into the event horizon technically. I'm not sure if the EH can increase in size out past the old EH tho. The EH is a really weird place because space and time break down at that point in time doesn't it?

Thought experiment. As you are falling towards the black hole space time is warped more and more. With the rubber sheet analogy you travel slightly further when you travel in a straight line through a gravity well then you do if there was no gravity well. The deeper the gravity well the further the distance. With a BH the EH represents a gravity well that is infinitely deep and even in your local frame of reference you have to travel an infinitely long time to actually reach it. Your speed would increase the closer you get to the EH coming closer and closer to C but never reaching it.

Even a photon should never approach the EH. The problem, as I understand it, is that there is, as of yet, no model for how a BH actually could grow because of this effect. Now if matter and energy is collecting close to the EH then I think that the EH could expand but I don't know if this actually causes that matter to then be within the BH or still just outside of it.

If I'm off base then I would love to hear the explanation on how an object actually could pass the EH.

astromark
2008-Dec-15, 08:21 AM
All is well... ( must have been in need of sleep ) an astronomers enemy. Mugs and jeff... thanks.
As to Wayne Francis ; I do not agree that matter can not reach the EH and on into the BH proper. BUT... I might be wrong., and will enjoy reading why I am wrong. Its my specialty subject. :(... I understand your point and would like to see more on this. A particle ( any ) falling toward a black hole and not having the radial velocity to orbit must I am sure end up in the black hole itself. After all that EH you talk of is not a real place at all is it. It being just that point of no escape for light. This idea that time slows to all most zero is I am almost sure only a matter of perspective. For me, If I were to go straight into a BH. I am going to get there, or my molecular remnants will.... If you could explain my error I will be pleased.

tommac
2008-Dec-16, 04:30 PM
We are talking about near the EH of a black hole. Not from inside the EH.

I can not see why this has not thus far been said... If light is escaping from it then it is not a black hole.
Light attempting to transverse the distance from the hart of the black hole to reach my eye would need to exceed C. or the gravity force exerted upon it.
The gravity of that mass must exceed the speed of light or a black hole, it is not.

tommac
2008-Dec-16, 04:39 PM
In free fall near an event horizon you are approaching the speed of light. To hover you need to decelerate to a standstill. With a rocket holding the spacecraft in place it will be like standing on a planet with superpowered gravity, with unsupported objects whizzing by you nearly at the speed of light. .

The key here is decelerate with respect to what?
I could argue that when you are in freefall you are not moving with respect to the space-time around you.

To not fall you need to travel equal to the speed at the speed that space-time is being pulled into the BH. this of course is true for all gravitational sources.

The movement is relative to a perception of space time.
You see a surface of the earth ( because you are travelling at less than the speed of light ) and you are travelling towards it. However relative to everything else in your local vicinity you are not moving ... like if you were inside an elevator.

In order to hover you need to travel at escape velocity relative to everything else in your imediate area.

tommac
2008-Dec-16, 04:41 PM
Hang on, some wild statements here.
Photons have no mass. They are NOT being "pulled down by gravity" but following straight paths in a space-time distorted by the mass of the black hole.
Nick-picking, maybe, but let's get it right.

What is the difference? Gravity = curvature of space time ... PERIOD.

tommac
2008-Dec-16, 04:43 PM
Not A but B when A and B are synonymous ... NO !
I see the distinction between suggesting 'the photon is held by the force of gravity' and, 'the space it is moving through is being distorted by gravity'
Are we talking of the same thing here..? When the mass of the BH is such that it distorts the space near it. Light can only reach C as a velocity. If the gravity is shrinking space faster than C its escape is impossible. Is that clear enough for you ?

Isnt that the definition of gravity? What other definition is there?

tommac
2008-Dec-16, 04:49 PM
I posted once in ATM to propose that inside of a black hole relative movement is actually away from the singulary.

The thought is that as you moved closer to the singulary space-time becomes so warped that your perception would be of movement away.

As you get closer your space-time becomes much more warped in comparison to your movement.

From this I jumped and stated that we could in theory be inside of a black hole and the red shift and moving away of all of the galaxies is caused by this effect.

From my understanding the hypothesized geometry of a black hole wouldn't even let something that could travel faster then C to escape it. Just like nothing actually every passes into the event horizon technically. I'm not sure if the EH can increase in size out past the old EH tho. The EH is a really weird place because space and time break down at that point in time doesn't it?

Thought experiment. As you are falling towards the black hole space time is warped more and more. With the rubber sheet analogy you travel slightly further when you travel in a straight line through a gravity well then you do if there was no gravity well. The deeper the gravity well the further the distance. With a BH the EH represents a gravity well that is infinitely deep and even in your local frame of reference you have to travel an infinitely long time to actually reach it. Your speed would increase the closer you get to the EH coming closer and closer to C but never reaching it.

Even a photon should never approach the EH. The problem, as I understand it, is that there is, as of yet, no model for how a BH actually could grow because of this effect. Now if matter and energy is collecting close to the EH then I think that the EH could expand but I don't know if this actually causes that matter to then be within the BH or still just outside of it.

If I'm off base then I would love to hear the explanation on how an object actually could pass the EH.

tommac
2008-Dec-16, 04:53 PM
The black hole grows because of the potential gravity near the event Horizon.
It is most notible in a collision of 2 black holes. As they get close to each other their EH stretch because of the potential gravity in that area.

When a star gets consumed by a BH ... it flattens around the EH but that makes the EH slightly more massive which creates a greater gravitational potential at that area.

It is true that time is stopped there ( relative to us ) but the mass is nearly infinitely dense when the star is close.

Even a photon should never approach the EH. The problem, as I understand it, is that there is, as of yet, no model for how a BH actually could grow because of this effect. Now if matter and energy is collecting close to the EH then I think that the EH could expand but I don't know if this actually causes that matter to then be within the BH or still just outside of it.

If I'm off base then I would love to hear the explanation on how an object actually could pass the EH.

tommac
2008-Dec-16, 05:07 PM
Well think of the way the speed of light is constant ...
Take the old light on a train vs light on the track vs differnent observers.

As we watch you fall into the BH we see your watch has just about stopped.

In order for speed of light to stay constant. Space-time needs to warp constantly. So in the direction of you movement space flattens as time slows. I believe we see you as stuck and pancaked.

Locally however you are torn appart by the differences in gravitational pull between your head and your feet and even that atoms that are in your body.

And this is really where my question is how does the person falling at the speed of light relative to everything other than his local vicinity view the rest of the universe. I think that space time is becoming smaller for him but at a signifigant rate. The amount of gravity from being inside of the BH creates a series of black holes some how. It is not like he can see the singularity just because he is inside of the EH in fact the effect will get worse as the amount of space time warpage increases.

All is well... ( must have been in need of sleep ) an astronomers enemy. Mugs and jeff... thanks.
As to Wayne Francis ; I do not agree that matter can not reach the EH and on into the BH proper. BUT... I might be wrong., and will enjoy reading why I am wrong. Its my specialty subject. :(... I understand your point and would like to see more on this. A particle ( any ) falling toward a black hole and not having the radial velocity to orbit must I am sure end up in the black hole itself. After all that EH you talk of is not a real place at all is it. It being just that point of no escape for light. This idea that time slows to all most zero is I am almost sure only a matter of perspective. For me, If I were to go straight into a BH. I am going to get there, or my molecular remnants will.... If you could explain my error I will be pleased.

mugaliens
2008-Dec-16, 05:53 PM
...we could in theory be inside of a black hole and the red shift and moving away of all of the galaxies is caused by this effect.

If that were true, we'd be rather flat right about now...

pzkpfw
2008-Dec-16, 07:37 PM
tommac, this starts to look like an ATM thread, not a Q looking for A.

(Q&A is for questions to be answered by the mainstream. Your speculation is for the ATM sub-forum, even if you think it is relevant to the question.)

tommac
2008-Dec-17, 12:49 AM
If that were true, we'd be rather flat right about now...

Yes to external observers. We really only would be a hologram

tommac
2008-Dec-17, 12:50 AM
tommac, this starts to look like an ATM thread, not a Q looking for A.

(Q&A is for questions to be answered by the mainstream. Your speculation is for the ATM sub-forum, even if you think it is relevant to the question.)

Agreed lets get back to the OP ...

Just noticed that someone else seemed to be going down the thought pattern that i went down on that ATM thread.

WayneFrancis
2008-Dec-17, 05:46 AM
The black hole grows because of the potential gravity near the event Horizon.
It is most notible in a collision of 2 black holes. As they get close to each other their EH stretch because of the potential gravity in that area.

When a star gets consumed by a BH ... it flattens around the EH but that makes the EH slightly more massive which creates a greater gravitational potential at that area.

It is true that time is stopped there ( relative to us ) but the mass is nearly infinitely dense when the star is close.

This is how I was thinking of it. Not so much that the mass passed through the EH but the EH kind of jumped past the point at which the mass had been collecting.

tommac
2008-Dec-17, 04:27 PM
This is how I was thinking of it. Not so much that the mass passed through the EH but the EH kind of jumped past the point at which the mass had been collecting.

That is acutally an interesting way to look at it.

However I think that too much emphasis is given to the EH. The EH is merely a mathmatical point where all kinds of crazy stuff happens.

However there is really nothing there, it is just a point of equilibrium where space time as we know breaks down.

As mass is added to the general area the sphere* of equilibrium grows due to the additional mass.

As any two masses get close enough to each other ( 1 1/2 * the radius apart ???? or maybe something to do with the center of gravity ) then the point inbetween the two masses has a deeper gravitational well than on the surface ????

Sorry confusing myself here with the math ... but anyway .. the potential gravity is effected from both masses

What I wanted to see is if a black hole situation could exist from say two nuetron stars coming close enough to each other. right before 2 neutron stars collide ( or maybe even at the point of collision ) The point at the center of mass may be greater than either of the Neutron stars themselves.

Could that ever produce a gravity well deep enough for a black hole?

Lets take a hypothetical situation where you have two stars that are very close to a black hole state. lets say 95% of the speed of light gravitation effect.
As they got closer say 1 ft apart. Could the well deepen at any point of the system to produce a black hole ?