PeterDonis's latest activity

This assumes that ##f## is constant along all Eulerian worldlines, so that once you've moved past a Eulerian worldline with a given...

While you're inside the bubble, yes. The question is what happens as you move through the bubble wall. The respective 4-velocities are...

Actually, I realized I don't have to work this out--it is ##\gamma##, because that's the time dilation factor relative to Eulerian...

But you don't get out of it--that's the point. The bubble is moving at ##v_s > 1## rightward. If you are outside the bubble to the right...

Yes, and that raises an issue that the left-moving case doesn't raise: when the right-moving observer gets to the right edge of the...

The "push" to the right that the bubble gives any worldline, regardless of ##\gamma##, of course helps you to get to the destination...

Of course worldlines exist where it isn't constant. But if you're trying to capture the idea of "moving at a certain speed along the...

But if you stay put, obviously you're accumulating zero odometer distance--you're just letting the bubble carry you. That seems to me...

It would if, for example, a worldline with the ##\gamma## I gave, or at least some reasonable ##\gamma##, but moving to the right...

Then I'm really confused about what you meant, since I just took your odometer distance definition and constructed a worldline with a...

Ah, I see. Well, to the extent that your odometer distance inside the bubble is a lot less than, say, 4.3 light years, that's still true...

I'm not sure what you mean by this either. If we want to find a ##\hat{v}## with nonzero odometer distance by your definition, we just...

I'm not sure what you mean by this. There are Eulerian worldlines outside the bubble as well, and using them as the "road" doesn't...

Both of these seem like they're more or less rediscovering the Bardeen black hole (a misnomer as the solution actually contains no true...

All of this is of course highly speculative, since we have no evidence in the relevant physical regime and aren't likely to get any any...