I think that spirits are bound by gravity, but not to the extent that they were when they had a body, loss of mass means loss of gravitational pull.
Let's look at this a lil deeper, everything is made out of something, light, energy, and matter is all composed of particles of one kind or another. Light for example, it seems to not be effected by gravity at all, but that is wrong, just the gravity we know is too weak to make any noticeable changes to the path of light. A star being consumed by the insane strength of a black hole bends light and pulls it in as well, for even light can not escape.
But then there is the question of if a spirit is made up of some kind of particles, how can it pass through objects, light can not.
About 6 months ago, some scientists, sent a message from one computer to another containing on one word "test" using neutrinos, which is a sub atomic particles. The real interesting part of this is it was sent underground through 100 yards of concrete.
With knowing this, and knowing that there are still particles that have yet to be identified, I find it very possible that our spirit has mass, and maybe some day, will be able to seen more easily.
Food for thought, has anyone here ever seen the show called "dark matters, twisted but true". To make a long story short, since this is already to long as it is. A guy figures out a way to weigh the human body on death, any thing that the body may loose (fluids, etc) is kept on the custom scale, but yet, every time a person died on the scale, the body always lost some weight, even as lil as 3/4 ounce, it always lost weight, he believed he proved the soul has mass. But no one ever followed up on it. True story, if any one is interested, ill provide a link so you can see it for your self.
Sorry for my long rant.
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