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 Be the first pioneers to continue the Astronomy Discussions at our new Astronomy meeting place...The Space and Astronomy Agora Doing Wierd Stuff With Paper Forum List | Follow Ups | Post Message | Back to Thread Topics | In Response ToPosted by SlySi on August 12, 2000 13:42:22 UTC

Hey Ybbid
The simple answer is, sadly, no. People are still unsure as to what gravity actually is, but it seems that it is either the interchange of particles (dubbed `gravitons`) between objects to cause a force (in the same way that particles are exchanged in electrical attractions between, say, protons and electrons).
The other possibility is that gravity is a `warping` of the space occupied by a massive body (most noticable with a star or planet, though gravity is still exerted by small objects).
So when a small body gets close to, say, a star, the warping of space means that the object `falls` toward the star (just like rolling a ball down a hill, but, confusingly, in three dimensions).

So a photon in a beam of light travelling toward a star falls down this well, altering its direction, just like any other object.

Gravity`s effect on time is wierder though, but think of it like this. We`re talking about space bending, so lets bend some stuff. Start with a piece of paper. Assume it has no thickness, just length and width, and then bend it. As soon as you start to bend it, you introduce a third dimension, height. It is impossible to bend a two dimension shape without adding a third dimension.

Now think of bending a three dimensional shape - not just changing its shape, but in the same way that the paper was bent (don`t try too hard, because it gives you a mean headache). It can`t be done without adding an extra dimension - time. So, in warped 3d space, the warp is FOUR-DIMENSIONAL! So the gravity warp has an effect on time.

Its really difficult to describe something you can`t see, but I hope this makes just a little bit of sense...

Seeya

SlySi