Re: another student question

[Jack Uretsky <jlu@HEP.ANL.GOV>]

        The first student made sense.  Einstein was troubled by this
point and introduced an extra "force" into his equations to make the
universe static.
        The second student's statement is a non-sequitur. "Bent
space-time" does not mean that bodies stop behaving as though there
are no forces acting upon them.  You've got to "bend" space AND time
in such a way that Newtonian gravity still appears valid for small
bending.
                                        Regards,
                                                Jack

Adam was by constitution and proclivity a scientist; I was the same, and
we loved to call ourselves by that great name...Our first memorable
scientific discovery was the law that water and like fluids run downhill,
not up.
                          Mark Twain, <Extract from Eve's Autobiography>

On Wed, 26 Jan 2000, Cliff Parker wrote:

> Another student question today...  We were talking about the
> expanding universe.  I suggested that the universe could never
> stop expanding and assume a static state because the
> gravitational attraction of every bit of matter upon every other
> bit of matter would cause it to immediately begin to collapse.
> One students suggested that if Einstein's view of gravitational
> effects being caused by bent space-time were true then all
> massive objects could be at rest because there would be no
> gravitational force and according to Newton's first law objects
> at rest can stay at rest.  Once again an idea I had never
> considered.  His ideas seem reasonable to me.  I am interested in
> receiving informed comments.
>
> Cliff Parker