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> You're assuming the gravitational field can't permeate the wormhole. In your first scenario, the gravity well would extend out of the other side of the wormhole.

That would be even worse, I replied to the same thing here: https://news.ycombinator.com/item?id=12301858

> A wormhole is in no way a gravitational discontinuity

A movable one certainly is, and a non movable one doesn't make any sense from a relativity point of view.

> Ellis Wormhole

Did you read your own link? "and there is no gravity"

There's a reason they say that. And there is no place in the universe without gravity. It's a mathematical solution, not a representation of the physical world.



> and a non movable one doesn't make any sense from a relativity point of view

Do you agree that you can't "leave the universe" in the sense of travelling past the information-propagation wavefront of the Big Bang—even in a case where our universe begins to shrink and that wavefront starts to come toward us?

If yes, then a non-movable wormhole can be justified exactly like that: it's part of that same wavefront—part of the topological outer surface of the universe, not an object "in" the universe.


You are implying absolute coordinates by saying that. It's similar to saying the universe has a center - the place where the big bang started.


Can you define what you mean here by discontinuity? I meant that the function of the gravitational field is continuous everywhere under the topology of the manifold, the mathematical definition. I see no discontinuity, but perhaps you're using a different definition?

The "no gravity" line there means the stress tensor is zero, and this is a so-called "vacuum solution." Essentially all closed form solutions to the field equations are vacuum solutions because it's almost impossible to write a closed form solution otherwise.


> I see no discontinuity, but perhaps you're using a different definition?

Sorry. The gravitational field of the object you just sent through the wormhole, not the gravitational field of the wormhole itself.




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