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What is singularity?
How come of it?
How come of it?
DM said:Quoting Stephen Hawkin's definition:
"A point in space-time at which the space-time curvature becomes infinite."
Nonetheless I'd like to read a more extended version of this definition from more knowledgeable people.
I am not sure that there is a completely accepted technical definition.AMD_K8L said:What is singularity?
By the Penrose-Hawking singularity theorems, any "reasonable" classical spacetime must be singular. Very roughly, in any "reasonable" classical spacetime, gravity is so stong that the fabric of spacetime gets ripped, thus creating an "edge".How come of it?
Is it Singularities are a unlimited dense point without any volume?AMD_K8L said:What is singularity?
How come of it?
DM said:Besides super duper definitions of singularities like Wikipedias', is there anyone else in this forum with sufficient knowledge on this matter that is confidently capable of stating, in the simplest possible terms, what this phenomenon is all about?
No. That sentence doesn't actually make much sense, quite apart from it being the wrong interpretation.Intuitive said:Would it be natural to say that a Singularity is a condensed infinite continuum point where all Dimensions could be experienced through observation all at once because of the infinite curvature?
Hmmm, well people who are perhaps more knowledgable than me can correct me, but a singularity is only a singularity from another frame of reference, am I right? In the frame itself there is no singularity right? Hence no breakdown of laws right?coalquay404 said:To use the more usual notion (i.e., from popularizations of science such as Hawking's books), a singularity is a point where the predictable nature of physics breaks down because the curvature predicted by general relativity at that point is infinite.
Wrong actually, a singularity in one frame of reference would be a singularity in any frame of reference.MeJennifer said:Hmmm, well people who are perhaps more knowledgable than me can correct me, but a singularity is only a singularity from another frame of reference, am I right? In the frame itself there is no singularity right? Hence no breakdown of laws right?
My definition of a singularity is "a point in space where any of the properties of matter or space-time become singular - i.e. infinite or zero. Thus in the limit density, pressure and space-time curvature become infinite and volume becomes zero.Would be funny if laws in nature would break down, for why would they be defined as laws? :)
Really? So is that described by some kind of theorem or so?Garth said:Wrong actually, a singularity in one frame of reference would be a singularity in any frame of reference.
Are you confusing the singularity itself with the event horizon around that singularity?MeJennifer said:Really? So is that described by some kind of theorem or so?
It appears counterintuitive to me.
What could be an infinity to an outside frame of reference does not have to be one locally right?
Take for instance a measurement of an object from an outside frame of reference that becomes a singularity. Time grinds to a halt and volume becomes zero right? But inside, does time stop as well and does voume become zero as well?
Seems that I am missing something here with regards to your assertion that a singularity is frame of reference independent.
Sorry, but I am still not getting it.Garth said:At the genuine singularity at the centre there is no time - it doesn't 'grind to a halt', there is no way of measuring it at all, it has become singular.
It gets squashed until in the limit its density and temperature become infinite and its volume zero.MeJennifer said:Sorry, but I am still not getting it.![]()
Let's assume some very small object getting caught by a black hole. At one point it passes the event horizon and after that it gets drawn closer to the center.
Now I understand that for any outside frame of reference (both inside and outside the event horizon) is appears as if the object is going towards a singularity. But for the object itself? How could it become a singularity?
I'm not sure I understand that statement.It seems to me, and I suppose I am wrong about it, that a singularity is a singularity for all outside frames of references but that the space-time of an infinitessimal small size regarded as the singularity for the outside frames of references is not.
Ok then let me reword it.I'm not sure I understand that statement. The singularity, at the centre of the event horizon, is a - well - singularity.
MeJennifer said:Hmmm, well people who are perhaps more knowledgable than me can correct me, but a singularity is only a singularity from another frame of reference, am I right? In the frame itself there is no singularity right? Hence no breakdown of laws right?
Would be funny if laws in nature would break down, for why would they be defined as laws? :)
Unless it is a theorem or so, stating that it is defined as such is not an answer at all.coalquay404 said:No, a singularity is a globally defined quantity so it is a a singularity in all frames of reference.
Of course it does, at the singularity itself, (not at the event horizon where just the Schwarzschild coordinates become singular,) there are no measurements of space and time, they have become singular and undefinable,MeJennifer said:For instance, an object occupying an infinitessimally small region of space drawn inside a black hole does not encounter anything unusual in its local measurements of space and time, even when it is eventually drawn into the singularity.
Yes.Am I to believe that for that small region everything simply from one point in time to another becomes undefined?