Re: General Relativity question

From: N:dlzc D:aol T:com \(dlzc\) (net_at_nospam.com)
Date: 03/18/05 

Date: Thu, 17 Mar 2005 18:51:46 -0700

Dear mikeinsb:

<mikeinsb@hotmail.com> wrote in message
news:1111102841.986143.254580@g14g2000cwa.googlegroups.com...
> I've taken high school and basic college physics. I have a
> question
> about gravity. I understand that the greater a gravitational
> field, the
> larger space gets stretched into the time dimension for an
> observer
> inside that gravitational field. I can picture this in a 2
> physical
> dimension, one time dimension cooridinate system as a massive
> ball
> depressing a rubber mat.

NOT the time axis. The stretching is supposed to represent the
alteration of "straight" in the 2D representation of space.

> Where the mat is being "pressed into" is the
> time dimension. In this coordinate system I can imagine if
> there is
> only one mass, say a marble, then this marble will start moving
> "down"
> into the time dimension at the speed of light. If this marble
> is moving
> to the side, it is no longergoing "down" at the speed of light,
> but a
> fraction of it, as its total velocity (sideways + down) will
> always
> equal the speed of light.
>
> Tell me if I'm wrong so far with this model...

This model doesn't EVER get right. I'd suggest you not spend
much more effort on the rubber *** analogy.

David A. Smith

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