Recent content by DrSnarl

Thank you for the explanations, Dave and PAllen! I think I get it now. I will read through those papers to try to iron out the remaining kinks. Thanks for being patient!

Thank you, I will take a look.

So if a rocket had side boosters near the front - so that both the front and the back were accelerating independently but at the same rate - then the rocket would break in half as the front portion and back portion were contracted away from each other?

The thing that is confusing about that is this: what makes the front of the rocket special? Why would the front of the rocket "not have moved yet"? If you added a nose needle to the rocket, would it now be the front of the nose needle that had not yet moved? It doesn't seem like adding...

I do not feel so bad now - it appears that the problem I have with this rocket experiment is illustrated by the Bell spaceship paradox. A quick internet search reveals conflicting explanations that yield conflicting results. Is there a scientific consensus on whether or not the "string would...

Yes, I agree, I was wrong. The source of my error lies in how I was attempting to explain why length contraction occurs. I think here is the basic thing I do not understand: what happens to the rocket on the other side of the wall when it accelerates? Assume instantaneous acceleration...

Let's place the rocket and the wall at distance "x". After acceleration has finished, the perceived distance of the rocket should be: x' = γ(1-v/c)x x' will be less than x - in other words, the rocket will have moved backwards through the wall in your perception. This is flat out wrong, as...

Actually, the entire rocket would not reappear at once; you would see the back appear before the front.

If that is true, then consider what would happen when a rocket on the far side of a distant wall accelerates away from you. Due to Lorentz contraction, it would appear to you as though the rocket contracted backwards THROUGH the wall. If, on the other hand, Lorentz contraction was just an...

OK, I now remember why I thought that accelerating causes a remote observer to think you've traveled through time. I thought that the resulting time shift depending on distance was what created the perception of length contraction. So after step 4), wouldn't "home rocket" be in the future...

Nice. :) I had not heard that one before.

Or more accurately, SR does indeed dictate that FTL travel or information transfer IS time travel, as we have been discussing.

You are right. In the first thought experiment, I was not treating the time shift due to acceleration as being frame invariant (as you and others pointed out, but I now understand what you meant). In the second thought experiment, I for some reason decided that accelerating causes remote...

That's just a matter of perspective. It moving to your past is the same as you moving to its future. Either way, when you accelerate towards it, you will think that its clocks are all advanced from where they were before you accelerated, no?

It looks like I remembered the details incorrectly, but the gist is the same. Here is a writeup I found about it at John Cramer's Alternate View site (a great site, by the way): http://www.analogsf.com/0612/altview.shtml