Steve Mynott wrote:
> discuss
>
> :-)
>
> ----- Forwarded message from [EMAIL PROTECTED] -----
>
> Subject: Gravity Can Be Challenged!
> X-List: [EMAIL PROTECTED]
>
> Gravity is like a river, and planets are like dips in the plane of space.
> Therefore, gravity, like water, takes the path of least resistance. So,
> you can build a canoe to navigate water, than you can build a simple device
> to navigate gravity. Just shape it right and it will float!
>
> Let me know if you have any suggestions on the shape of that craft.
Slightly wrong analogy -- I'd say more accurately that gravity is a river, and
objects in the influence of gravity take the path of least resistance...
However, just as a conoe navigates water with certain limitations, mass can
navigate gravity with certain limitations -- namely, according to convention you
can't travel, or have come from, outside of your current lightcone, whimsically
known as "elsewhere":
\ future /
\ /
\ /
\ /
elsewhere(fut) \ /
X
/ \ elsewhere(past)
/ \
/ \
/ \
/ past \
[you'll need a proportional font to be able to see this]
Now, the interesting part is to be able to tip the lightcone using a large
gravitational mass -- (or, to re-direct the river, using the jargon) -- because
then your allowable 'future' according to far-off observers can actually be in
their past. There's a drawback to this kind of timemachine though: you can only
travel back to the time of creation of this timemachine, no further back (because
it doesn't exist then). This is an interesting solution to the problem of "if
time travel is possible, why are we not seeing people from the future?".
lex
