Whilst I find all this fascinating , the idea that a black hole can ' swallow ' light for example is pretty mind boggling. How can light just vanish?
I mean we look at this M87 and obviously its how it looked around 55 million years ago, the light reaching us now, and I understand at the moment the visible universe is around 12 billion years of ' sight'.
Perhaps a black hole just attracts matter etc , spins it around and emits it somewhere else in one form or another ......building new stars ?
I disagree with a lot that is said about black holes, and I think some of it amounts to mistakes (which have contributed to difficulties such as the black hole information paradox).
The errors start with the Schwarzschild model. This is the spherically symmetric (non-rotating) solution of the equations of general relativity with no mass. It has a spherical event horizon and a singularity at its centre.
The logical error is in thinking that this model is accurate for a real object observed in real time. There is an implied assumption that this is what the black hole is like "now". Firstly there is no such thing as "now" in general relativity. Rather there is the causal past, the causal future and the space-like region of points in space-time which can neither be communicated with or can communicate with the observer.
The nearest to "now" is the space-like points (neither past nor future), but we can only observe these at some point in the future (when they may enter the past light cone). So let's deal with the entirety of all points that can be observed by an external observer over all time into the future.
This set of points does not include the event horizon. It does not include anything inside it. It does not include any hypothetical singularity or quantum non-singularity.
So to me, none of this ever exists to an external observer. What they observe is material falling into a very heavy object and becoming increasingly red-shifted in a way which means the material spends forever just outside where an event horizon would be.
Some people will claim this is just a mirage and what really happens is that material falls the black hole, passes its event horizon and ends up with a nasty crunch at a singularity (or quantum gravity mess that replaces it). The problem with this is that at every point in time, the event horizon is in front of the falling victim.
One might say this is a bit like the Zeno paradox. But is it? The total energy of the falling object reaches infinity as it reaches the theoretical event horizon: it is a massive object reaching the speed of light. Is this a real phenomenon?
Something else happens. This is some sort of catastrophe that allows the material to be re-radiated as something probably indistinguishable from Hawking radiation after an extremely long time (so that the outside Universe becomes cool enough for the flow of energy to be outward).
Black Holes do not exist !!!! If your first concept is incorrect you can not build more. One can not put a universe in a point, And next, the universe did not start from a point either. You can't do both from your logic !!!
Black Holes do not exist !!!! If your first concept is incorrect you can not build more. One can not put a universe in a point, And next, the universe did not start from a point either. You can't do both from your logic !!!
you sound like a jehova witness
Is an infernol a POINT ?
Well then at what size did the inferno start ?
The notions of time and distance that are used in cosmology are not quite what they seem due to relativity. Both are only defined in a specific local Lorentz frame, but the distances between points in the Universe "now" (at a similar time since the big bang in different co-moving frames) are made up of a mixture of Lorentz frames all moving at different speeds relative to each other. The cosmological redshift is due to this changing of frames, but changing frames also changes distances.
If you picked a point far away in the Universe and were able to change your velocity so that it didn't look red-shifted, it would suddenly also appear - indeed be - nearer by the same factor. So what is the "right" distance? As it appears from here, or moving at the same speed as it, or adding up all the distances in a set of comoving frames between the two?
A "CMB" location is a part of the Universe that is far enough away for us to see it as it was at 380,000 years after the Big Bang. You can think of it "now" being as old as our part of the Universe, 13.8 billion light years. But if you went there as fast as possible, how old would it be in cosmological time when you got there?
This gets confusing for me here. The light reaching us from that place is presently coming from 380,000 cosmological time (CT, say). If you accelerated to a tremendous speed very quickly, it would seem to me that you could not have gone far enough for this to change much. But by that time there would be spectacular Lorentz contraction in the direction of the location. So it would not take very long to get there and it would still be young.
This must be wrong - we have to respect the speed of light in the time of the destination and surely our initial distance has to be very large in a frame corresponding to our destination. The shakiest claim seems to be that while you accelerate, the distant location does not appear to age much. Perhaps this is far from true, despite that (in principle) you might not travel very far?
Wow, all these notes over something that does not exist.
Just speculation:
1) The collapse of black hole does not stop at some point short of 'point ' dimensions? What slows up the collapse so that it appears to have dimensions? Is it just the time required to add material from the accretion disc?
2) Black hole status is achieved when light is unable to escape. What is mass requirement for that stage?
3) Most importantly what is role of gravity in black hole?
Is a point reached where gravity cannot escape the black hole? Are the 'gravitons' at some point inhibited from leaving the black hole? Or are 'gravitons' themselves anti-gravity particles not themselves subject to gravity or any other force?
If the gravitons cannot be kept within the black hole then we can speak of gravity decay since some mass/ energy must leave to keep up gravity 'field' ( Note ..we do NOT want to have mysticism introduced by reference to 'field' in the sense that no energy is required to maintain the 'field'.)
But then does 'gravity decay' occur whereever gravity exists? Sigh .. wish we knew just what gravity is. Nice to speak of 'waves' 'fields' and 'gravitons'. Unsatisfactory current state of knowledge.
4) What happens after (if it does ) black hole singularity occurs and at the same time gravity is unable to function ? (We can look upon it as a state in which 'gravitons' cannot escape.)
Do we have near infinite mass and point size? As such it cannot interact with ordinary mass since it would be so small though dense that it could pass through an atom without interacting...and no longer has field. Something akin to 'dark matter'?
To be sure point dimension black holes seem to share characteristics of the pre big bang near point source. The consideration that we can detect multiple black holes and it is hard to see how they can coalesce if gravity cannot escape suggests an approach to multiple 'big bangs' or indeed continuous 'big bangs'.
Just speculation.