Endless torment

That's a fair point. So then one might expect the ghost to continue their motion tangential to the orbit of the earth, and so they'll float away.

However, the theory of general relativity suggests that gravity isn't really like other forces. It doesn't push or pull anything at all; but rather its bends the fabric of time and space. Objects 'falling' due to gravity, or 'in orbit' around a planet are actually moving in a direct straight line in curved space-time. And this is why gravity still applies to massless objects such as light. So then, I'd say the ghost would still be affected by gravity - and that their main concern would be falling into the earth rather than drifting away.

😆 this comment really amused me, i guess the basic physics plus ghosts in the same matter-of-fact statement

But that would imply that the ghost is a physical thing right?

Does it come to existence when we are born? Or does it appear when we die?

Does It behave like matter? If not, properties like velocity, inertia or energy wouldn't apply.

The comic is really amusing to bring forth these questions

And it would still be gone in an instant

Nah, it won't be perfect. Some, tiny divergent velocity will exist.

Yup. Same as the time travel meme that was on the front page recently, this relies on there being a fixed inertial frame which is not a thing in our weird universe.