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Old 27-June-2003, 05:58 PM
HankSolo HankSolo is offline
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Join Date: Jul 2002
Location: Long Island, NY
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Kilopi, thanks for the bullet/ball example. I read where you wrote that elsewhere, and I keep it in mind. Time has to be a factor. And you're right, the path is not closed, it would be a spiral due to motion, in my opinion.

But..... last night I came up with two breakthroughs, at least in terms of explaining this in a manner I can understand. However it was 11:30pm and time for bed (cigar time in my backyard is my thinking time) so I only got a hour or two to think it through before conking out. In both, there really is no force of attraction involved. Now remember, I'm not a scientist, so please excuse and/or correct any errors I make. Let me start with the first, since it directly relates to your bullet/ball example, and it leads into the second example that has to do with the apparent attraction of gravity. I'm still writing up the second one and hope to post it today for your opinions. For all I know, these are the accepted theories. I'm sure much greater minds than mine have tackled this issue. But I have never seen it explained quite this way so that a layman can understand. And it brings up some interesting implications.

So on to analogy #1. The analogy again involves a paper cone, and I'll assume the path through space-time is closed to simplify. But this time we must add time to the example.

Previously, I compared our motion through space-time to a straight line drawn on a piece of paper. Mass warps space-time, and sufficient mass will result in a circular path in space-time for an object traveling through it (really a spiral, but that complicates it a bit and I don't see it as necessary for the example). The result would be like bending the paper into a cone so that both ends of the line meet, with the source of the gravity well existing at the closed point of the cone. Really, the better comparison would be to a curved funnel instead of a straight cone, but that's hard to do with paper. Either way, an object on the line still thinks it is traveling in a straight line, and in reality there is no attraction to the source of the gravity well. But to an observer, the object "orbits" the source.

Now, if you add time and the ball/bullet example to this, a faster object would be a line higher up the inside of the cone (farther away from the source), and a slower object would be a line lower inside the cone (closer to the source). Once you go slow enough to make contact with the source of the well, friction from that contact will keep you there unless you can increase your velocity again. And if you travel fast enough, your line won't be in the cone at all and you will not be caught in the gravity well.

So there has to be a relationship between the amount of space-time distance that an object travels in a given amount of time, and where that object's orbit exists in the gravity well. Therefore, Pluto should be traveling much faster than Mercury. The farther out you orbit, the faster you should be going. The closer objects may seem to be faster, but that is because they are deeper in the gravity well, and actually traveling through more and more stretched-out space-time the closer they get, making them appear faster. Likewise, an object traveling towards the sun appears to accelerate, but actually its velocity does not change in relation to space-time as it is still covering the same amount of space-time per second, but the space-time is being stretched more and more the closer it gets. But if the sun were removed from the picture and everything traveled in a flat space-time, Mercury should be much slower than Pluto. Is this true?

If it isn't true, then that obviously flaws the example. That's my first problem with this, since despite the logic of the example, it seems to me that a fast Pluto would exceed the sun's escape velocity at that distance, and a slow Mercury would crash into the sun. But that's answered in analogy #2 which I'm working on.

Then there's my second problem with this example. There is a need for some sort of time/distance (ie speed) relationship with the gravity well, where a faster object orbits farther away than a slower object. Why does this relationship exist? I don't know, but this relationship is further illustrated in my analogy #2.

Lastly, if we take a motionless object (relative to the sun) that enters the sun's gravity well due to the fact that the sun is moving closer to it, it should never gain any motion due to the sun, and once the sun's gravity well leaves the area, the object should still remain motionless in its original spot. Like something floating motionless on the water would appear to move up and down as a wave passes, but it remains in its original spot after the wave passes. (again, #2)

So that brings me to my second analogy which also involves ocean waves... but I don't think I'll have time today. Gotta go. Basically, objects in motion "surf" gravity and space-time, and this is the cause of the apparent attraction and repulsion (which determines orbital distance). I bet you can guess that I was at the beach yesterday . And motionless objects (motionless relative to the center of the universe) have no attractive properties, and cannot be moved from their stationary spot by gravity. Maybe I’ll paste what I’ve written so far into another post, since otherwise I won’t be back until Monday.

But... how does #1 sound so far?