Relativity declares that no material object can exceed the speed of light in a vacuum, and the math and experimental evidence bear this out thus far. So then if we want to sail the universe, we have to do something a little different, and I've always wanted starships.

Consider. General Relativity tells us that gravity is not a property of mass as such, but is in fact an effect of the interaction between mass and spacetime. To visualize this, compress spacetime in your mind by one dimension and picture it as a flat, infinitely elastic sheet, with time being the dimension normal to the surface. So, you drop a mass into spacetime, and it sinks in a bit, creating a depression in spacetime, something I like to call a mass-warp. And the more massive the object, the deeper and steeper the mass-warp.

Now, if gravity is an effect of that interaction, it follows logically that inertia is also an effect. That what resists acceleration is the mass-warp itself. Picture our object in the bottom of it's mass-warp, moving along, and the mass-warp moving right along with it. Now, as the thing moves faster, the mass-warp begins to distort a bit. The side to the front gets a bit steeper, to the back a bit shallower. So as we approach "c" and our kinetic energy, and therefore our mass approaches infinity, our mass-warp starts to look very strange indeed, tipped in the direction of motion and very deep. This by the way agrees quite well with what Relativity tells us local space will look like at these speeds.

But just suppose for a moment that we could decouple our mass from spacetime, in effect rising up out of our mass-warp. We would become effectively mass-less, and inertia would be negated, thus allowing us to skate along at just about any speed we desired. Of course one wonders what happens when we drop our mass back into spacetime. Might tend to splash a bit.

Of course the problem is that we don't really have any clue how mass couples into spacetime. We don't really know what gravity is or how it propagates, much less how to control it. We can quantify it, write equations about it and say what it does, but that is all, and it ain't much. We can't even detect gravity except in the crudest sense with the technologies at hand.

Now I admit to having an idea for an instrumentality which might allow us to detect a gravity wave as it passes, but the thing would, by it's nature, be ridiculously expensive to build. NASA is looking into something similar right now, though a lot smaller.

Be that as it may, if we want starships, we have two choices. We can build slower than light ships and take years and centuries between stars, or we can figure out how to sidestep Dr. Einstein. And I'm sure I am not the only person who thinks about this stuff.

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Re: Is the Speed of Light REALLY the Limit?" by cwarner7_11 on 09/25/2008 12:57 AM (score 1)