Worm-holes. Do they actually go anywhere?

[Ironclad]

Here's a piccy of a worm-hole in space (space-time?).
Anyhoo, I don't get it, probably because I am not a boffin, mind.
But riddle me this: I was told, as a kid, that a super massive gravity well could cause a worm-hole in space & to traverse it would/could allow transport across vast distances, to be spat out at a 'white-hole'.
BUT those bowling-ball on a rubber mat examples show space in 2D, surely in 3D (or 4D) the gravity-well is more like an onion; a spherical power of incremental something something. There is no worm-like hole to anywhere but the middle of... oblivion. Surely.

Also, what exactly IS a white-hole? An area of un-gravity?? Or a TV nonsense?

[Atheist-Lite]

There is a small room inside of which sits a computer terminal. All wormholes lead to the small room. The monitor is old and dusty. It is not switched on. The room is dark and the door leading out is locked from the outside. No one ever visits this room. When they say wormholes lead no where it is because they do not know about this room.

[Ironclad]

This is not awesome!

[SPMaximus]

Only John Crichton is qualified to answer such a question

[surreptitious57]

Only John Crichton is qualified to answer such a question:

Alastair Reynolds would know too: brilliant sci-fi author and astrophysicist.

[Gawdzilla Sama]

Wormholes are purely theoretical and highly problematical.

[Atheist-Lite]

Wormholes are purely theoretical and highly problematical.

Not anymore check my other thread.