Travelling through a wormhole in space

[tomBitonti]

A wormhole is a shortcut through a curved space. To go through normal space from points A to B, you travel some distance X. Go between points A and B through a wormhole, and you go some distance Y.

Now, you have three cases. Y=0 is the "instantaneous travel" option. The wormhole is a portal, and there is zero distance between its ends.

But zero is a very specific number. All in all, you'd kind of expect Y to have some value, but one that specific? That would have to be a specific result of the math, to come out that elegantly.

The more realistic idea is that Y has some non-zero value. If X>Y, we travel some distance through the wormhole, and it is a shortcut. But that doesn't mean it is actually short, on human scales. It is ~4 light years to Alpha Centauri. A trip of only 2 light years to get there would be a shortcut, but still a long distance on human scales.

There's also the possibility that Y > X, that the wormhole trip is *longer* than the trip through normal space. It would be kinda dumb to spend all the effort warping spacetime and taking a longer trip, rather than a shorter one, but I think the math allows it. We just aren't interested i this, so we disregard it.

Additional text omitted.

Wouldn't it be easier to work directly with the wormhole geometry? That's what the linked PDF does, with, effectively, a wormhole length as one of the wormhole parameters. Also, in their analysis, time dilation effects are virtually nil, so the length can be used directly to measure transit times.

There is an interesting example of one of the cases: Greg Egan, in "Diaspora" (Millennium, 1997), postulates that elementary particles are wormholes. But Egan's wormholes have Y=X, so not useful for crossing our universe. (But useful for entering a higher level dimension, since the worm holes have shape in higher dimensions and can be used to transport information and create material in the higher dimension space.)

From the wikipedia article (https://en.wikipedia.org/wiki/Diaspora_(novel)):

"An appended glossary explains many of the specialist terms in the novel. Egan invents several new theories of physics, beginning with Kozuch Theory, the dominant physics paradigm for nearly nine hundred years before the beginning of the novel. Kozuch Theory treats elementary particles as semi-point-like wormholes, whose properties can be explained entirely in terms of their geometries in six dimensions. Certain assumptions common to Egan's works inform the plot."

Thx!
TomB

 

[freyar]

Wow, blast from the past!

tomB, Umbran really is using the wormhole geometry, but he's just talking about it in somewhat less technical terms than the paper you linked. Also, you're right, the length of the wormhole is a parameter, but (assuming a wormhole does exist) that parameter should be determined by whatever matter creates the wormhole in the first place.