George W Harris wrote:
> Global conservation of mass/energy requires a
> simply connected space-time topology.
Actually, it's worse than that; even in a simply-connected spacetime
topology, the concept of the total amount of mass, energy, momentum,
angular momentum of the Universe is problematic in general relativity.
You can talk about one, but those familiar with general relativity know
that they're basically cheating.
But more im****tantly, global conservation of energy is not in any
meaningful sense true in general relativity. Indeed, our models of the
Universe require that it be violated (namely, with cosmological red****ft
-- photons traversing an expanding spacetime are losing energy, but the
energy isn't going anywhere).
In general relativity, one can only talk about _local_ (that is, in the
vicinity of a point) conservation laws. There are no global
conservation laws in our best theories that deal with the large-scale
structure and evolution of the Universe, as strange as that sounds.
--
Erik Max Francis && max@[EMAIL PROTECTED]
&& http://www.alcyone.com/max/
San Jose, CA, USA && 37 18 N 121 57 W && AIM, Y!M erikmaxfrancis
More than eight I'll call you / Less I'll call it a day
-- Anggun
|
