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| Doug Freyburger... |
 Posted: Tue Oct 27, 2009 8:29 am |
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Navigaiter wrote:
[quote]
I read that no matter which direction an astronomer looks, all stars
have redshift and so are moving away from us. Therefore we just might
be at the center of creation?
[/quote]
All it means is we are not near the edge, if there even *is* an edge.
With a universe big enough there would be vast regions not near the
edge. With an unbounded universe there is no edge at all.
So how far back would we need to look before there's an estimate of
boundaries for a total shape and if there is an edge how far we are from
it? A lot farther back than we can see now. With an unbounded universe
farther back than we can ever see.
[quote]Anyway, the "Big Bang" is a bust.
[/quote]
The evidence in favor of it keeps growing. Drat that evidence stuff
anyways.
[quote]Amd 80% of the universe is unknowable, indetectable "Dark Matter"
so cosmology is a comic book ;-]
[/quote]
I think dark energy is getting towards epicycles. Dark matter is a
question of when and how it gets detected. It would be rather
interesting if new colliders fail to detect it, though. |
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| Sylvia Else... |
| Posted: Tue Oct 27, 2009 7:06 pm |
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Jonathan wrote:
[quote]"Sylvia Else" <sylvia at (no spam) not.at.this.address> wrote in message
news:011c5035$0$11345$c3e8da3 at (no spam) news.astraweb.com...
.
Well, it may not be the one and only habitat worthy of intelligence, but it
might indeed by the only one where intelligence at a human level exists.
The appearance of intelligence in humans involved at least two, and probably
more, separate occasions where our ancestors nearly became extinct, with the
accompanying evolutionary pressure to acquire increased intelligence. But
there's only a small margin for error - and actually becoming extinct was on
the face of it a much more likely outcome.
But you have it all wrong. The natural tendency of the universe
is to increase in order over time. To self organize, where the
highest levels of order, such as intelligence, are inevitable.
[/quote]
Evolution proceeds by selecting for those inviduals who are most
successful at reproduction. It selects for increased intelligence only
when reproductive success is a result. Typically, this is when the less
intelligent individuals die because the environment is too taxing.
Intelligence can be a reproductive liability. Look at birth rates in
first world countries.
Even pre-humans went happily along for a couple of million years without
developing this allegedly inevitable intelligence.
Until there was a drought in Africa that meant only the brightest survived.
Sylvia. |
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| Jonathan... |
| Posted: Tue Oct 27, 2009 11:05 pm |
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"Sylvia Else" <sylvia at (no spam) not.at.this.address> wrote in message
news:011c5035$0$11345$c3e8da3 at (no spam) news.astraweb.com...
..
[quote]
Well, it may not be the one and only habitat worthy of intelligence, but it
might indeed by the only one where intelligence at a human level exists.
The appearance of intelligence in humans involved at least two, and probably
more, separate occasions where our ancestors nearly became extinct, with the
accompanying evolutionary pressure to acquire increased intelligence. But
there's only a small margin for error - and actually becoming extinct was on
the face of it a much more likely outcome.
[/quote]
But you have it all wrong. The natural tendency of the universe
is to increase in order over time. To self organize, where the
highest levels of order, such as intelligence, are inevitable.
Not a fluke of chance!
Please join the new century, what they taught you only
ten years ago wrt the evolution of the universe and life
are completely out of date.
http://www.calresco.org/themes.htm
There are two primary reasons why life and intelligence are
the natural and expected result, not the result of a rare
combination of chance events.
One, what does the Second Law do best? It randomizes
and breaks things down into their components. If you only
look at that aspect then your chance driven view is logical.
But what happens when a system becomes totally disordered?
What happens at zero order? Any random event will disturb
that system, changing it's level of order. And a zero order
system can only /increase/ in order when disturbed.
This gives a mechanism for spontaneous order emerging
from total disorder.
And two, fitness peaks behave the same way as a gravity well.
In that the larger the peak, the greater the basin of attraction.
So just like gravity, evolving systems are more likely to randomly
fall into a higher fitness peak than a lower one. Just like a mass
is more likely to randomly fall into a larger gravity well than
a weaker one.
So you see, random interactions serve to /generate/
spontaneous order....and....persistent hill climbing.
THE DICE ARE LOADED!
The greater the number of random events, the more they tend to
sum to increasing order and evolution. And even more
importantly, this is true for the physical universe as
well as life, the two share a /common process/ of
evolution.
Jonathan
> Sylvia |
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| Jonathan... |
| Posted: Tue Oct 27, 2009 11:05 pm |
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"Wayne Throop" <throopw at (no spam) sheol.org> wrote in message news:1256616261 at (no spam) sheol.org...
[quote]Whatever gave you the bizarre idea that it's "indetectable"?
It's been detected fairly directly, by it's effects on light,
same way you "detect" an apple or a bicycle. As well as being
detectable by its effects on nearby non-Dark matter.
[/quote]
Maybe this is more semantics, but
I think it's more accurate to say dark energy and matter have
been indirectly detected, by their effects. But the fact remains
they haven't a clue what it is that is causing these effects.
They have an idea how it behaves, but that's not the same
thing as saying something is directly observed.
The way dark energy behaves is very interesting though.
And it's behavior explains why dark energy was a minor
player early on, but at almost the exact time life evolved
on Earth, dark energy emerged (evolved) to become
enough of a force to start a second phase of universal
expansion. An expansion due to the repulsive nature
(not attractive) of this new kind of energy/matter.
It should be a source of great curiosity, if not wonder, to
think that this new form of energy, the second phase of
universal expansion it generated, and ...life all evolved
simultaneously. What is the relationship between dark energy
and....life???
The reason for this can be seen in it's behavior. At high
rates of expansion, dark energy is a small component.
But as the expansion slows, there's a point where potential
energy becomes dominant over kinetic energy. At that point
dark energy become /repulsive/, and an ever growing
component. Starting a second period of expansion.
Dark energy and dark matter increase in magnitude over time
closing the universe and providing the reason to believe
in a ....new cyclic model.
A Quintessential Introduction to Dark Energy
Center for Theoretical Science, Princeton University
"Most of the energy in the universe consists of some form of dark energy
that is gravitationally self-repulsive and that is causing the expansion rate
of the universe to accelerate. The possible candidates are a vacuum energy
density (or, equivalently, a cosmological constant) and quintessence, a
time-evolving, spatially inhomogeneous component with negative pressure."
"A common model of quintessence is the energy density associated
with a scalar field Q slowly rolling down a potential (V (Q)).
The pressure of the scalar field, p = 1/2Qsquared - V(Q)
is negative if the field rolls slowly enough that the kinetic energy density
is less than the potential energy density."
"Should we believe, as most cosmologists suggest, that this is the last
missing piece of the puzzle and our understanding of the universe is
virtually complete? Or have we just uncovered a deep dark secret
that will revolutionize our whole view of the universe and
our place in it? I must confess to my own prejudice that
the latter seems more likely."
http://wwwphy.princeton.edu/~steinh/
All the great discoveries are yet to come.
We still live in the Dark Ages!
Jonathan
s
s
[quote]
Wayne Throop throopw at (no spam) sheol.org http://sheol.org/throopw[/quote] |
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| Van Chocstraw... |
| Posted: Wed Oct 28, 2009 7:14 am |
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Greg D. Moore (Strider) wrote:
[quote]No. No more than two ants on the surface of a balloon that is expanding
think the other ant is moving away from them.
So why is Andromeda heading towards us?[/quote] |
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| Greg D. Moore (Strider)... |
| Posted: Wed Oct 28, 2009 7:48 am |
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Guest
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"Van Chocstraw" <boobooililililil at (no spam) roadrunner.com> wrote in message
news:pJKdnUtG84BV3nXXnZ2dnUVZ_jxi4p2d at (no spam) giganews.com...
[quote]Greg D. Moore (Strider) wrote:
No. No more than two ants on the surface of a balloon that is expanding
think the other ant is moving away from them.
So why is Andromeda heading towards us?
[/quote]
Because while the Universe in general is expanding, individual objects
within it have their own relative motion.
It's the difference between two ants standing still on an expanding balloon
vs. two ants walking towards each other on an expanding balloon. |
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| Van Chocstraw... |
| Posted: Fri Oct 30, 2009 6:56 am |
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Guest
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Greg D. Moore (Strider) wrote:
[quote]"Van Chocstraw" <boobooililililil at (no spam) roadrunner.com> wrote in message
news:pJKdnUtG84BV3nXXnZ2dnUVZ_jxi4p2d at (no spam) giganews.com...
Greg D. Moore (Strider) wrote:
No. No more than two ants on the surface of a balloon that is expanding
think the other ant is moving away from them.
So why is Andromeda heading towards us?
Because while the Universe in general is expanding, individual objects
within it have their own relative motion.
It's the difference between two ants standing still on an expanding balloon
vs. two ants walking towards each other on an expanding balloon.
So in fact, some of the universe is expanding, some is not.[/quote] |
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| Fred J. McCall... |
| Posted: Fri Oct 30, 2009 9:59 am |
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Guest
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Van Chocstraw <boobooililililil at (no spam) roadrunner.com> wrote:
:Greg D. Moore (Strider) wrote:
:> "Van Chocstraw" <boobooililililil at (no spam) roadrunner.com> wrote in message
:> news:pJKdnUtG84BV3nXXnZ2dnUVZ_jxi4p2d at (no spam) giganews.com...
:>> Greg D. Moore (Strider) wrote:
:>>> No. No more than two ants on the surface of a balloon that is expanding
:>>> think the other ant is moving away from them.
:>>>
:>>>
:>>>
:>> So why is Andromeda heading towards us?
:>
:> Because while the Universe in general is expanding, individual objects
:> within it have their own relative motion.
:>
:> It's the difference between two ants standing still on an expanding balloon
:> vs. two ants walking towards each other on an expanding balloon.
:>
:
:So in fact, some of the universe is expanding, some is not.
:
Wrong.
--
"Ordinarily he is insane. But he has lucid moments when he is
only stupid."
-- Heinrich Heine |
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| Greg D. Moore (Strider)... |
| Posted: Fri Oct 30, 2009 8:20 pm |
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Guest
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"Van Chocstraw" <boobooililililil at (no spam) roadrunner.com> wrote in message
news:KdOdnT8rZOkBf3fXnZ2dnUVZ_gVi4p2d at (no spam) giganews.com...
[quote]Greg D. Moore (Strider) wrote:
"Van Chocstraw" <boobooililililil at (no spam) roadrunner.com> wrote in message
news:pJKdnUtG84BV3nXXnZ2dnUVZ_jxi4p2d at (no spam) giganews.com...
Greg D. Moore (Strider) wrote:
No. No more than two ants on the surface of a balloon that is
expanding think the other ant is moving away from them.
So why is Andromeda heading towards us?
Because while the Universe in general is expanding, individual objects
within it have their own relative motion.
It's the difference between two ants standing still on an expanding
balloon vs. two ants walking towards each other on an expanding balloon.
So in fact, some of the universe is expanding, some is not.
[/quote]
No.
The UNIVERSE is expanding. But objects in the universe also have motion
independent of the expansion. |
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