| From: | Adam Getchell acgetchell@*******.edu |
|---|---|
| Subject: | Flat/Curved Earth |
| Date: | Fri, 26 Feb 1999 13:55:16 -0800 |
>space. Don't think of the surface of the earth as a sphere, but as a
>flat plane curved into the shape of a sphere (by gravity). So, the earth
>is both flat and round :)
Well, not exactly, but somewhat.
Globally, the universe is thought to be flat. There are revelations in
Cosmology since more accurate measures of Hubble's constant have been taken
and neutrinos have been shown to have mass. There are thought to be about
10E^55 photons in the Universe and an order of magnitude more neutrinos.
Most nuclear reactions release neutrinos at some point, energy which is
essentially 'lost' due to the neutrino's extremely weak interaction with
matter.
At any rate, gravity curves spacetime (a 4D Lorentzian manifold if you keep
up with Kip Thorne) into geodesics, more or less. A geodesic is a path that
minimizes total proper distance. Spacetime around the earth is affected by
the Sun, Moon, and Earth itself, a classic case of the pathological (ie
nearly unsolvable) n-body problem in gravitation. Nevertheless, one might
characterize this condition as "weak" such that General Relativity boils
down to a linearized theory aka Newton's law of Gravitation.
Or another way to look at it, local spacetime is flat.
The easiest way to think about it is that mass tells gravity how to curve,
and gravity tells mass where to move.
>Hmmm... I wonder if there are any forces that can warp the astral plane
>like gravity does to the physical plane..
Totems? Metaplanes?
>-David B.
--Adam
acgetchell@*******.edu
"Invincibility is in oneself, vulnerability in the opponent." --Sun Tzu
