How does gravity travel through wormholes?

FtlIsAwesome
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Suppose a civilization had the technology to make wormholes. It would likely place them in orbit over its planets. Say one end orbiting Earth and the other end orbiting Mars.

Now, it makes sense that gravity would travel through the wormhole, and the planets would alter each others' orbit.
To simplify it, let's assume the the wormhole ends are massless--having a balanced amount of positive mass and negative mass.

To avoid this effect the wormhole ends need to be placed far from the planets, if you wanted to intentionally alter the planets' trajectories you'd place the ends closer; as a general rule.

How do we calculate the effect of gravity if we know the masses of planets, their trajectories, and the trajectories of the wormhole ends?
 
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The mouth of the wormhole is going to act like it has some mass M. Said mass will change if something massive passes through the wormhole, but not otherwise. So the equations that describe it's orbit won't be significantly different from the equations that describe anything else's orbit.

For a popularized reference (by a physicist author) see http://www.npl.washington.edu/AV/altvw69.html.

[add]If you want something slightly more formal, but still readable, try Visser's "Lorentzian Wormholes".
 
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What type of wormhole are you talking about here? Normally we talks about wormholes that create a connection by extremely curved space. However, you have to remember that gravity itself is just curvature of space time in general relativity. And curvature of wormhole is so huge (at the singularity point), that curvature caused by Earth is negligibly small. Thus objects just move along Geodesics of curvature of wormholes.
 
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