0 Members and 1 Guest are viewing this topic.

If length contraction is so extreme at the event horizon of a black hole does this mean that the radius of the event horizon that we observe as outsiders appears smaller than it actually is? If so then by what proportion of its actual extent?

Quote from: jeffreyH on 27/04/2015 22:23:01If length contraction is so extreme at the event horizon of a black hole does this mean that the radius of the event horizon that we observe as outsiders appears smaller than it actually is? If so then by what proportion of its actual extent?What length contraction are you talking about? I know of no length contractions inherent in the spacetime geometry of a black hole.

Let's try a thought experiment. We position ourselves 1 million metres away from the event horizon of a black hole. We then feed one million metre length rods end to tail and feed them towards the black hole. We feed then towards the event horizon. As the get nearer to the event horizon they eventually become stretched due to the tidal forces. We could ultimately determine that the event horizon is more than 1 million metres away because the million rods are too long for the distance we have calculated..

How do you know that though?

Thanks Pete. I can always guarantee to learn something when we debate. I may not always digest it immediately. Yes of course I was wrong about the contraction. I realized that after I had posted.