Re: A stellar explosion has smashed the record for most distant object in the known universe.

On Wed, 29 Apr 2009 18:47:39 -0700, Islander <nospam@xxxxxxxxxxx>
wrote:

rick++ wrote:
On Apr 29, 9:32 am, mg <mgkel...@xxxxxxxxx> wrote:

Our smallness really does boggle the mind, doesn't it. The only
half-way appropriate comment I can think to make, other than that, is
contained in this little prayer:

Other people are disturbed the known universe is finite:
only 13.7 billion years old and 27 billion light years wide.
They ask what is "before" the beginning or "beyond" the edge.
Stephan Hawking saws this is like asking what is "north"
of Earth's North Pole.

OK, now this is something that I don't understand. As we look further
and further out into the known universe we are looking back in time as
well. So, if we look far enough, we will see, not the edge of the
universe, but the origin of the universe. That origin, as evidenced by
radio signals associated with the Big Bang, is everywhere equidistant
from us as nearly as we can tell. We are at the center of the universe.
Likewise, the theory claims, every other body in the universe is
equidistant from the Big Bang. Yet, there are vast distances separating
us! How can that be?


I don't know the answer, but I'll take a shot that the big
bang was not a symmetrical event. The fact that the
galaxies are in clumps might suggest that, but that could
also be attributed to quantum randomness. Quantum
random events were probably galaxy-cluster sized in
the first picoseconds of the big bang.

I'm not sure that the fact that the big bang radiation
is uniform over the sky means that we're at the center.
If we're not at the center, the stuff from farther away has
a greater distance to go, but there's more of it in that
direction. This exactly cancels out, analogous to what
Newton proved, there is no resultant gravity anywhere
inside a uniform shell: the nearer material pulls harder,
but there's mores material at the far end in the same
angular slice. It exactly compensates. Thus if you
were inside a circular cell and had only gravity to go
by, you couldn't tell how near you were to any part of
the shell.

Earth is a series of concentric shells, so the gravity
at the center is zero, though the pressure is enormous.

A related thing that Newton showed is that if you're
outside (as opposed to inside) a uniform shell, the
gravity is the same as if all the mass of the shell were
concentrated at one point in the center of the shell.
Thus to determine the gravitational pull at some point
inside the earth, you just have to compute the mass
of everything closer to the center than you are,
and the distance you are from the center. The net
pull of everything closer to the surface than you are
is shells that you're "inside", so the net pull of those
is zero.

The cosmic background radiation comes from
one concentric shell, so no matter how close to or
far from any side we are, the effect will be the same
in all directions. This is all just my guess, there
might be something wrong with it.

Also, the universe is supposed to curve back
on itself in four dimensions, and if so then saying
that we're at the center of the universe is like
saying that San Francisco of Sydney is the center
of the surface of the earth. There is of course no
center of the surface of the earth. Wherever you
are on it, that looks like the center. A city on the
surface of the earth sits on a two-dimensional
figure that curves in three-dimensional space,
and our solar system sits on a three-dimensional
figure that curves in four-dimensional space,
thus they're analogous.




.

Relevant Pages

  • Re: neutrino interaction
    ... ripples can represent curve spacetime. ... >> when the ENGINES OF THE UNIVERSE ... stars around the center of a galaxi, gravity ... understand that the earth is not flat. ...
    (sci.physics)
  • Re: Questions on faster than light
    ... Wormholes and Warp Drive require Negative Mass." ... is the same thing in our universe outside the BH, ... Since the angle of the BH gravity well 'wall' is ... Compare its center to the center of the earth for a moment. ...
    (sci.physics)
  • Re: A stellar explosion has smashed the record for most distant object in the known universe.
    ... So, if we look far enough, we will see, not the edge of the universe, but the origin of the universe. ... That origin, as evidenced by radio signals associated with the Big Bang, is everywhere equidistant from us as nearly as we can tell. ... Thus if you were inside a circular cell and had only gravity to go by, you couldn't tell how near you were to any part of the shell. ... and if so then saying that we're at the center of the universe is like saying that San Francisco of Sydney is the center of the surface of the earth. ...
    (soc.retirement)
  • Re: Hiding some cavourite?
    ... from that patch of Earth below it. ... Universe attracts objects on the Earth's surface, ... under the Cavorite sheet the Earth's full, unopposed gravity would be ... Even detecting the gravitational attraction of the two strongest ...
    (rec.arts.sf.science)
  • Giant Blob headed to Earth by 5500 AD ? Blame it on the Gum Nebula star explosion @15,000 years ago,
    ... Blame it on the Gum Nebula: ... CAUSES INCREASE IN EARTH QUAKES, AND STORMS, LIKE THE RECENT EARTH ... on the Formation of the Universe. ... The Force of Gravity ...
    (sci.physics)
Loading