Wormholes in Space

[lwcamp]

Originally Posted by vicky_molokh

Just how does one figure if this is so or not-quite-so. How approximate is 'approximately Newtonian gravity' in such context?

This is always going to be an approximation. It is just that over scales of solar systems and galaxies and galactic superclusters, it is a very good approximation. The errors in this approximation are roughly of the order of the general relativistic corrections to Newtonian gravity over a shell (or other closed surface) surrounding your region of interest at distances sufficiently far away that you get as close to Newtonian gravity as possible over that shell. Which, for the case of starts and galaxies and whatnot, makes this a very very good approximation.

Originally Posted by vicky_molokh

Also, what are the walls of a wormhole's throat like? What happens when an object with mass touches / collides with a wall?

There really are no walls. Not in space-time, anyway. The local wormhole traffic authority might put some up. Or maybe the engineers need to put up walls in order to make the wormhole work.

There is one direction where, if you move with a component of your velocity in that direction, you go through the wormhole and end up on the other side. The other two directions are periodic - if you move in the plane defined by those two directions you will eventually circle back around to end up where you started again. If your velocity has components along both the perpendicular and parallel directions to the throat, you will spiral around. This means that if you look in the direction perpendicular to the throat, you will see wildly distorted ring-images of yourself from the light that you emit which comes back around into your eye.

Luke