Yousuf Khan wrote:
N:dlzc D:aol T:com (dlzc) wrote:

Okay great, then assuming by some discovery we find out
how much of the universe is outside of our viewing range,
will that affect the calculations for the age of the universe?



How could we find that out? Light (and its close cousin, virtual
photons) is our only means of detecting *anything*.


That's why I said "assuming by some discovery", which should obviously
mean it's hypothetical.

No. As I have said, the CMBR a billion years ago (baed on
observations) indicated an age of the Universe that was a billion
years younger.


Okay that's a good possibility, how do we know the CMBR is cooling? Are
we measuring microscopic changes in temperature of the CMBR and then
extrapolating backwards? Or are we just taking our theories about the
temperature of the Big Bang and curve fitting backwards from today to a
billion years ago? Basically what is the mark left on things from a
billion years ago that what would indicate the CMBR was warmer back then?

Well, how do we know the distribution of matter isn't highly iron?



The spectrum of the stars is that of mostly hydrogen ad helium.


Yeah, the spectrum of the stars is like that, but what about the halo?
There's little to no sprectrum to be seen there.

We don't even know what dark matter is composed of yet.



Yes, we know what it isn't, however. And baryonic matter (iron,
hydrogen and the like) is what it isn't.


What if Milgrom's MOND is right at least to some extent? It won't banish
the existence of dark matter, but the dark matter itself doesn't have to
be as massive as we need it to be right now.

What if all of the
stuff out in the galactic halos are long dead star cores (including
neutron stars and stellar blackholes), which somehow migrate out into
the halo over time?



These areas are full of dust. How is it that the "neutron stars and
stellar blackholes" prevent discovery by NOT consuming the dust and
producing the ever-present X-rays? Like their counterparts in less
dusty areas manage to do...


Okay, understood. Then let's change the parameters a little bit, how
about long dead star cores, but only the type below 1.4 solar masses,
and not the exotic ones above 1.4 solar masses, like neutrons and
blacks. Again, the sieving effect caused by some quirky nature of MOND.

Separated out by gravity in some sort of natural
galactic centrifuge. Afterall it seems like the laws of gravity are
starting to undergo modifications these days as we do more
detailed observations of the rest of the universe -- perhaps a
galactic centrifuge is a quite logical outcome of the laws that
we will eventually discover?



Not too likley. No such motion is evident, and we can see several
galaxies "closely" and quite clearly.


Maybe I should've been a bit more specific when I said that the theories
of gravity are undergoing modification, before. I *was* thinking of the
MOND theories partially. But it isn't just MOND there's other anamolies
being presented here too. Those anamolies can be explained by MOND, dark
matter, superstring theories, etc.

SPACE.com -- The Problem with Gravity: New Mission Would Probe Strange
Puzzle
http://www.space.com/scienceastronom...ay_041018.html

The particles represent the temperature of the hole. Not very much
mass is going to be produced this way. Even with all the holes we
have discovered. You are a few loads shy of a workable hypothesis.


Well, at various points in the life of the universe a lot of mass has
been locked away inside blackholes. Stephen Hawking said that blackholes
radiate their mass away as antimatter particles fall into them,
releasing their associated matter particles to keep living. If there is
a natural skew to the universe that prefers that a few more percentage
of antiparticles will fall into blackholes rather than particles, then
perhaps blackholes are a form of cosmic bank vault. In fact, Hawking
said that we should just now be seeing some microscopic blackholes with
masses the size of mountains or asteroids created during the big bang to
be completely disappearing right now, simply from the effects of vaccuum
energy eating away at them. At some point all blackholes (even the
biggest galactic ones) will have eaten away at most of the material
nearest to them, and there will be nothing else falling in to any great
rate, at that point the vaccuum energy eating away at their insides
might become a greater effect. Right now we're still depositing into the
blackhole banks, later we might be withdrawing.

The
new particles could go into refreshing the galactic gas clouds
for new star formation. And mass and energy conservation
would be preserved in the universe by the fact that every year,
more parts of the universe become inaccessible to us as they
go "beyond the rim".



There are surprises in store for us, don't worry. But our ticket is
one way, and we are going to end up cold and in the boonies... no
matter how large or old the Universe is.


And the Dark Energy force that's forcing the galaxies apart at an
accelerating rate, might at some future point switch over to a
decelerating and reversing force which could end up bringing everything
back together. But that might only be triggered by the universe becoming
sufficiently cold. No evidence for the Dark Energy doing that yet, but
then again there was no evidence for Dark Energy at all just a few years
ago -- and now there is.

Yousuf Khan

MOND is Dead? ...maybe
http://www.astro.ucla.edu/~wright/density.html#MOND
http://www.astro.ucla.edu/~wright/old_new_cosmo.html

22 Oct 2002 - The Chandra X-ray Observatory presented evidence
against the MOdification of Newtonian Dynamics (MOND) alternative
to dark matter theories. The August 2002 Scientific American has a
long article about MOND. The hot X-ray emitting gas around the
galaxy NGC 720 forms an ellipsoidal cloud, which requires an
ellipsoidal gravitational potential well. While an ellipsoidal
cloud of dark matter could provide such a well, MOND would
necessarily give a spherical potential well. In general MOND works
well on the scale of individual galaxies, but not for clusters of
galaxies. So why is MOND only maybe dead? Its supporters like
Milgrom are persistent and clever, and they may come up with a
MONDian explanation for NGC 720.