Cosmic Censorship

Discussion in 'Astronomy, Exobiology, & Cosmology' started by The God, Mar 30, 2017.

  1. The God Valued Senior Member

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  3. Schmelzer Valued Senior Member

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    I have never understood the point of this hypothesis. What we see in the past is, in GR, a quite naked singularity, the BB singularity.
     
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  5. Boris2 Valued Senior Member

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    Well, maybe. Thing is there was no "outside" to observe it from.
     
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  7. The God Valued Senior Member

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    Thats nice and quite damning from you.
     
  8. The God Valued Senior Member

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    Well, yes at t = 0, there was no outside to observe it from, but at some t > 0 there certainly was a point from where the inner mass was blackholish type and still visibly expanding.
     
  9. Michael 345 Valued Senior Member

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    ........in the late 1960s Roger Penrose proposed that there be some physical principle, as yet not understood, that excludes naked singularities as solutions to the equations of general relativity......

    Brilliant

    I propose there should be answers, physical principals and equations to all the physics we don't know or understand now

    Obvious???

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  10. Boris2 Valued Senior Member

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    There was? A singularity isn't a blackhole. A blackhole is a singularity with an event horizon. Naked singularities don't have event horizons.

    Well, if it is physics then there probably is. Whether we find an answer is another matter.
     
  11. Schmelzer Valued Senior Member

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    In the abstract Platonian world of ideas? In the real world, if there would be answers, equations and principles, we would have at least some understanding.

    Ok, there may be some differences. There is a lot of confusion about quantum theory, despite the fact that we have equations, principles, and answers to all practical questions. But this is a quite accidental problem, caused in particular by a strong influence of positivism which strongly rejected to discuss as lot of questions of interpretation as "metaphysical". In general, if there are equations, principles and answers, there is also understanding. So, if there is no understanding, something is missed.

    In the case of singularities, it is clear that everything is missed. The only thing which is clear is that the theory which gives the singularities is wrong, and, near the singularities, not even approximately true.

    In this sense, I don't even understand what could be the point of a "cosmic censorship" which hides the singularities. Anyway, even with all singularities hidden, the theory remains wrong. Some extremal version of positivism, if we do not see the singularities the theory predicts, the singularities do not exists, and therefore the theory has no problem?

    The only point where it could make sense is that it increases the region where GR may be reasonably applied as an approximation. If there would be a naked singularity, everything what is causally influenced by it would be unpredictable by GR.
     
  12. The God Valued Senior Member

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    If a mass is within its schwarzschild radius, then classical GR refers this as BH with one way towards r = 0. Now take a comfortable time after t = 0, stay at the outermost time, and look inward, this point will have such huge mass that it will be inside its EH.

    A singularity is nothing but division by zero...it is just that we don't know (rather we dont want to know) what is beyond EH, so we call it singularity as it moves towards a point where a/0 appears.
     
  13. Michael 345 Valued Senior Member

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    The point I was thinking about with my post

    RogerPenrose proposed that there be some physical principle, as yet not understood, that excludes naked singularities as solutions to the equations of general relativity

    seems to be stateing the obvious that we need a answer, and one which excludes naked singularities (although if we don't understand already how can anything can be excluded?)

    Of course we would like a answer (need perhaps to understand more)

    I think he would be better to try and put in simple terms for simple people (us or at least me) explainations of the problem

    Perhaps he has

    But the statement to me seemed strange

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  14. Boris2 Valued Senior Member

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    There is no EH to the singularity that, maybe, started the Universe. Because that would need space outside of the EH, and there wasn't any.

    GR isn't "wrong" because it doesn't include the singularity, it just doesn't apply. Just as Newtonian physics isn't "wrong" it just doesn't apply to some situations.
     
  15. Schmelzer Valued Senior Member

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    Flat Earth theory is also not "wrong", but simply doesn't apply to some situations?
     
  16. Michael 345 Valued Senior Member

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    Who knows?

    There might be a Discworld out in the Universe

    I would not bet on there being turtles all the way down

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  17. The God Valued Senior Member

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    Conclusion if I may;

    Cosmic Censorship = Fun, no physics.
     
  18. Boris2 Valued Senior Member

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    I guess if you don't know the actual reason behind Penrose coming up with this quote, ie GR etc, then that may be a conclusion you could draw. If you do know the physics then I guess it is far deeper than that simplistic answer.
     
  19. The God Valued Senior Member

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    Deeper?? What am I missing? And if it was deeper, then Feynman would have known the depth, why he expressed his ignorance?.

    The point is there is nothing like a naked singularity, that is too troublesome for physics, so keep it shrouded. It was a brilliant stroke by Feynman to perpetuate non-physics.
     
  20. Boris2 Valued Senior Member

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    LOL, this shit wont work with me. Go find paddoboy.
     
  21. The God Valued Senior Member

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    You claimed something "far deeper" without telling what that far deeper is? I personally feel this comes from a naive approach that anything stated by an established scientist shall have a meaning and that meaning will be deeper if not understood by literal translation. You are entitled to keep that approach.

    And by the way this is not shit, this exposes how people, not science, can come up with funny ideas to save on something in which they are deeply invested.
     
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  22. Fraggle Rocker Staff Member

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    But since we have no way to look beyond the BB, we cannot know whether that event was a singularity... or an event that occurs at random (or regular!) intervals.
     
  23. Write4U Valued Senior Member

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    Just a musing about the a zero state singularity which expanded at an unreasonable speed (the inflationary epoch)..

    If I consider say,a drop of water as a singularity in a zero state and a lake of water, also in a zero state..'If the drop of water comes in contact with the lake, the drop is absorbed and instantly becomes part of the much larger lake. Can we say that the drop instantly *inflated* to the size of the lake, or did it just become part of a larger whole (the lake), but creating a subtle wave function throughout the entire lake?.

    Now visualize a zero state brane making a singular contact with another but much larger brane, causing the smaller brane to instantly become part of the larger whole and also experience *symmetry breaking*, creating a dynamic but very subtle wave function?
    Could such a scenario be modelled?

    I know this sounds like woo, but there is always this superluminal expansion and conversion from zero state to dynamic state without an identifiable causality..
    There has to be a simple , possibly very subtle explanation to account for inflation and conversion from zero state to dynamic state.

    This may be of interest:
     
    Last edited: Apr 24, 2017

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