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Infinitely (Relatively) Smaller Black Holes

  1. Jan 20, 2010 #1
    This is my first posting to PF, so I do apologise if my post does not adhere to the etiquette of the forum.

    I had been considering black holes recently, and I had a thought/question which I am interested to hear people's feedback on, as I have not found a lot of information specifically on this concept:

    It is said that a person approaching a black hole will eventually be crushed by the overwhelming power of gravity. I wonder, rather than being crushed, something else may occur.

    Imagine that you begin your journey in a rocket on earth and head towards a known black hole. You accelerate towards the speed of light, and eventually you near the point where you have observed the event horizon to be from Earth. But instead of being crushed into a singularity, you realise something else, something you've been realising more and more on your journey towards the black hole. There is no event horizon here, but the event horizon has moved light years further ahead than from where you had observed it from the Earth.

    Relative to earth, you are travelling faster than the speed of light, and the size of your rocket is infititely small (no longer observable from Earth), but relative to your rocket, nothing has changed. Instead, all YOU see is more space: more galaxies, more stars. Galaxies and stars not visible to the Earth, but relative to your rocket they are moving around the same relatively similar speeds, and relatively similar sizes to your rocket.

    Looking ahead in the distance, you see the event horizon far ahead, much the same as the same as the horizon moves as you are sailing along in a ship.

    Could it be then, that at the same time we are looking at black holes wondering what is beyond the event horizon, we too are inside our own 'black hole' and some other civilization may be looking through their own telescopes at us.

    Another way of visualising this is to imagine a high resolution digital image of stars, say 1,000,000 px wide, by 1,000,000 px tall. But to fit it onto our screen, we need to zoom out quite away until the entire picture fits onto our 1920x1280 desktop. At that level, no matter how close we get to the screen, even with a magnifying glass, it may be impossible to see any planets around those stars. The resolution of the monitor is simply not high enough - it's our event horizon. Zooming in, new details are revealed...

    Not sure if this analogy works for people or not, but I hope I've made my question/thoughts clear. I'm not a physist, and I apologise if I've completely overlooked some well-known facts that negate what I've posted here. If so, I'm sure to learn something from it.

    I look forward to people's responses.
  2. jcsd
  3. Jan 20, 2010 #2
    1. Correct: when you approach the event horizon (seen from Earth) your apparent horizon recedes in front of you, so you never cross it, even inside the BH

    2. Looking back, you will see the universe you left. You dont see the whole history of the Universe. Contreintuitevely, light is redshifted (not infinitely blueshifted as many people expect)

    3. You can not look at the direction where the singularity is because the path to the singularity is timelike, so it is nowhere is space but in your future. You just see another matter falling and spagettified.

    4. The Kerr BH is a different story.
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