PeterDonis's latest activity

No we are in agreement that the peculiar velocity is c. The difference is the notion of distance traveled. You have not provided any...

I'm not sure I'd say it's minor, since it can mislead the viewer about whether the horizontal surfaces are spacelike, which is an...

Those light cones are, indeed off, but only that the right bound of the cones can approach horizontal, but never reach it. That is a...

So, then, it is obvious that for a traveler in the center of the bubble, using Eulerian observers to define a road, the odometer...

Actually, it is possible, even in the warp spacetime. For the Alcubierre metric, if we define the timelike congruence of "Eulerian"...

One simple calculation is that if ##v_s## is 2, then the slope of light cones well within the bubble is appx. ##2 \pm \sqrt 3##...

Consider a spacetime consisting of a static spherical shell with empty space both inside and outside. Consider two observers, one at...

Getting back to the notion of distance, and how to make sense of it in relation to the warp drive metric, a few common conventions in GR...

What does this mean? Can you give a specific example of a "superposition" that this question would apply to? Note that "superposition"...

Yes, that's now they would normally be modeled in QM, as a single two-photon system in an entangled state. What lack of delay? Several...

@Aloiz Burher I just used magic moderator powers to edit your post #5 to remove the long quote of the OP of this thread--not necessary...

It relates exactly to what you said. You said it was intuitive that proper time inside the bubble was the same as outside because both...

And this is an expectation which is false for almost any type of bubble or shell you can construct, where inside and far away are both...

Note the spacetime inside a spherical shell of matter is flat, but proper time for the at rest observer inside is NOT the same as for an...

Note that the paper I referenced previously references another paper by Natario which constructs a warp drive spacetime in which the...