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I am at a loss as to why the assumption is made that behind the event horizon matter must have a quasi infinite density, could there not be a further stage of commpression possible past the density of the Neutron star where the star has sunk to a diameter such that it is hidden behind the event horizon.Protons have a well defined diameter but why can't the constituent quarks not be forced even closer together.

Because we know that we don't know exactly what is inside a BH, I think it's dangerous to apply an assumption that requires us to know something, to the BH situation where we know that we don't know that something.

...they say the light cones are tilted towards the singularity...

this because space-time curvature is so high that a point object inside it have no other chance than to move towards the singularity (they say the light cones are tilted towards the singularity)

Oops - my misunderstanding.That's an interesting thought re the cone collapsing. If it could be viewed from outside, the the sides of the cone at the base would have to appear to start contracting inwards and eventually end up as a point (or a quantum object). At some point in this process it seems to me that the cone could pass through a phase where it appeared broadly symmetrical along the time (height) axis.

Let us imagine we are really in a black Hole, we certainly cannot escape tho we reach 'c' velocity, what do we see about us galaxies and even other black holes.Would it be any different inside any one of them?.

You would be in a gravitational freefall so I am not even sure that distant starlight would be blue shifted.

Yes, and there would be blue shift if you were somehow stopped or slowed by firing huge retro rockets. But if you had free-fallen into the BH you would have a huge velocity and moving away from the stars behind you so there would be a large doppler redshift which (I think) would exactly nullify the gravitational blue shift.

Do you mean like 2 cones base to base? That's what I was thinking.It wouldn't necessarily result in a symmetry along its time axis, though. Imagine the case of a cone the entire base of which intersects the EH at an angle. At the EH the cone would invert with its apex at the singularity.

Quote from: DoctorBeaver on 23/05/2008 20:39:23Do you mean like 2 cones base to base? That's what I was thinking.It wouldn't necessarily result in a symmetry along its time axis, though. Imagine the case of a cone the entire base of which intersects the EH at an angle. At the EH the cone would invert with its apex at the singularity.Sort of - because the cone would be in a gradient, the base would have to contract towards a point as it approached the singularity but I would imagine the sides of the cone to be smoothly curved and it would end up as a sort of elongated egg-shape, but with pointed ends instead of rounded ones.

All I think it actually signifies is that in such a situation there's only one possible future, which we know already

Light cannot escape from an EH, so the escape velocity is >c. But if an object free-falls across an EH, what is its velocity? I don't see that it necessarily has to be relativistic (That would be especially true of supermassive BHs).

In the case of a BH, the EH marks the point along the gravity gradient from the BH where the escape velocity from the BH is equal to c, so nothing within an EH can escape it by being given a sufficient initial velocity, because nothing can be imparted with a speed > c.

The light falling into the BH will be blue-shifted but as you accelerate towards the singularity the light will appear to be more and more red-shifted until you reach the point where your velocity approaches c and the apparent energy of the light reaching you approaches zero.

Quote from: LeeE on 24/05/2008 17:40:51Quote from: DoctorBeaver on 23/05/2008 20:39:23Do you mean like 2 cones base to base? That's what I was thinking.It wouldn't necessarily result in a symmetry along its time axis, though. Imagine the case of a cone the entire base of which intersects the EH at an angle. At the EH the cone would invert with its apex at the singularity.Sort of - because the cone would be in a gradient, the base would have to contract towards a point as it approached the singularity but I would imagine the sides of the cone to be smoothly curved and it would end up as a sort of elongated egg-shape, but with pointed ends instead of rounded ones.A fat, pointy-ended sausage! []QuoteAll I think it actually signifies is that in such a situation there's only one possible future, which we know alreadyIndeed. Until the entire base of the cone intersects the EH, all possible futures are still options. But when it does - SCHLOOOOOP!heh - can we say that the diminishing fatness of the sausage depends on the schloooopiness of the BH? Imagine presenting that in a paper! []

Quote from: DoctorBeaver on 24/05/2008 17:58:10Quote from: LeeE on 24/05/2008 17:40:51Quote from: DoctorBeaver on 23/05/2008 20:39:23Do you mean like 2 cones base to base? That's what I was thinking.It wouldn't necessarily result in a symmetry along its time axis, though. Imagine the case of a cone the entire base of which intersects the EH at an angle. At the EH the cone would invert with its apex at the singularity.Sort of - because the cone would be in a gradient, the base would have to contract towards a point as it approached the singularity but I would imagine the sides of the cone to be smoothly curved and it would end up as a sort of elongated egg-shape, but with pointed ends instead of rounded ones.A fat, pointy-ended sausage! []QuoteAll I think it actually signifies is that in such a situation there's only one possible future, which we know alreadyIndeed. Until the entire base of the cone intersects the EH, all possible futures are still options. But when it does - SCHLOOOOOP!heh - can we say that the diminishing fatness of the sausage depends on the schloooopiness of the BH? Imagine presenting that in a paper! []Hmm... fat pointy-ended sausages being drawn into a BH - just my base sense of humour but I can't help remembering a certain phrase concerning a fan and something that hit it.

I did not intend to Insinuate anything - It is purely my coarse sense of humour.However, were one to find oneself in such a situation (and assuming that one didn't want to be in it) I think that it's quite possible that some folk, obviously less cultured and refined than yourself, might actually use the phase I alluded to, but without realising how literally appropriate it might actually be, especially if the BH has any angular momentum.