## Surpassing the speed of light.

I think it is physically significant to the question of whether things can apear to exceed the speed of light. From equivilance we know the c is the same in every local frame. But really how can you say there *is* a local frame in GR at all; maybe a single 1D line representing a potential. But between potentials you can have the example I just gave. I don't see how that's not physically significant to this question. Or is it just significant when objects conveniently apear to travel slower than c?

 hi, i'm most likely the dumbest person around here but as i was making a report on black holes/white holes for my teacher i've stumbled across this forum and could not help from noticing that some people still use the natural laws of physics about talking beyond the event horizon and i've read that space and time become distorted as you are closing in on a black hole once you've crossed the horizon that space/time even switch places going on from this point,i get the fact that at the even horizon: gravity pull= speed of light, this is the "frozen effect" now as for the claim that time and space become extremly distorted approaching a black hole, and they shift places , could it not be that the gravitational pull is HIGHER then the speed of light beyond the event horizon? i'm not trying to be a know-it-all its is rather disturbing and hard to grasp how mucht a dimension as time is being influcent by mass, if someone could explain this to me, i would find it easier to grasp, if you want to anwser with formulas, be my guest, i had enough maths in school and i know how to use a search button to understand the formulas myself but please consider that spacetime inside a black hole becomes timespace :p or am i wrong about that? i got those ideas after reading it a couple of times on different sites
 Recognitions: Gold Member Science Advisor Staff Emeritus No one here is going to find a question like this annoying but many might be annoyed by the fact that you asked in someone else's thread! How about starting a thread for your question specifically. Oh, and it would help if you asked as specific a question as you could.

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 Quote by HallsofIvy No one here is going to find a question like this annoying but many might be annoyed by the fact that you asked in someone else's thread!
Especially a thread whose last previous post was two and a half years ago!

 Quote by franznietzsche The Latex engine has been behaving really problematic for me. I'm trying to get them fixed. Its completely displaying one wrong for me (its displaying a different latex code from elsewhere in my post in two places, when one of those should be something very different). The first displayed $$r \rightarrow 0$$ should be $$= G \frac{M m}{r} + \frac{mc^2}{\sqrt{1-\frac{v^2}{c^2}}} - mc^2$$ I have no idea why its displaying it wrong. Edit: Fixed it. Its all correct now. Bah, off to the feed back forum on this one.

QUESTION: Would you please post the way in which you came to a solution for your problem??? I have been following your work a little and would like to further understand this excellent example on surpassing the speed of light... Thank You... perrittj@yahoo.com

 Quote by perrittj QUESTION: Would you please post the way in which you came to a solution for your problem??? I have been following your work a little and would like to further understand this excellent example on surpassing the speed of light... Thank You...
Not likely. franznietzsche has not been here in a year and a half. But I'll step in.

He was not describing how to exceed the speed of light, he was showing mathematically why it can't be done.

Simply put, velocities do not add linearly at relativistic speeds.
Say it took you a week to get from zero to .9c.
Accelerating for another week would not get you beyond, c, it would just get you closer to c - maybe .99c.
For however long you accelerate, your speed will get closer and closer to c, but it will never reach it, let alone exceed it.
It's fairly straightforward math, if you punch in the numbers to the formula he provided.