Could Dark Matter Possibly Be . . .

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BMAONE23
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Re: Could Dark Matter Possibly Be . . .

Post by BMAONE23 » Thu Nov 13, 2008 12:21 am

Part 3
2001 12.5 billion years.
Clark, Stuart
Star date: The minimum age of the Universe is calculated using a new
radiometric approach. New Scientist. 7 February 2001.

2001 12.5 billion
February 7, 2001, Roger Cayrel et al measured amounts of the radioactive
elements thorium and uranium in an ancient star named CS31082-001
using a technique called radioactive cosmochronometry. ("The ages of the
oldest stars in the galaxy indicate a possible time when star formation began and provide a
minimum age for the universe,") Cayrel said. They calculated that
CS31082-001 is about 12.5 billion years old, with an error factor of
about
three billion years.
Cayrel, R et al. Measurement of Stellar age from uranium decay.
Nature. 8 February 2001. Vol 409, No. 6821.
http://physicsweb.org/article/news/5/2/5
http://www.afterabortion.com/universe.html


Kilkis 14.8 billion
http://www.perkel.com/nerd/relativity.htm

2002 - 12 to 13 billion years.
Harvey Richer of the University of British Columbia in Vancouver.
Studied the cooling of white dwarfs.
http://www.stardate.org/resources/news/ ... 00208.html

2003 - 13.7 billion years
Schwarzschild Bertram
WMAP Spacecraft Maps the Entie Cosmic Microwave Sky with Unprecedented Precision.
Physics Today. Vol 56, No. 4. April 2003.
http://www.gsfc.nasa.gov/topstory/2003/ ... sults.html
http://map.gsfc.nasa.gov/m_uni/uni_101age.html>


And this from 2002
http://www.spaceflightnow.com/news/n0204/24hubbleage/
Part 3

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Re: Could Dark Matter Possibly Be . . .

Post by Nereid » Thu Nov 13, 2008 2:07 am

Interesting inputs, thanks BMAONE23.

Upon checking, there seem to be some inaccuracies ...
BMAONE23 wrote:[...]

This site has references to various articles about the age of the universe.
http://www.ldolphin.org/univ-age.html
Not a very reliable webpage, IMHO ...
Appx. 1995 9.5 billion
Nial Tanvir
Nature 7 September 1995
Here's the abstract, per ADS:
New Hubble Space Telescope observations of Cepheid variable stars in the nearby galaxy M96 give a distance to the host galaxy group, Leo-I, of 11.6+/-0.8 Mpc. This value, used in conjunction with several reliable secondary indicators of relative distance, constrains the distances to more remote galaxy clusters, and yields a value of the Hubble constant (Ho=69+/-8 km/s/Mpc) that is independent of the velocity of the Leo-I group itself.
Doesn't seem to point to "9.5 billion years", but maybe I'm missing something?
10 billion years
Barry Madore
Studied Cephoid variable stars
There's no reference for this, so I can't check it.

In general, most of the reported ages are derived from estimates of the (local) Hubble constant (Butcher's and Bark Bok's excepted), and are quoted without the original estimated uncertainties ("errors"), which is unfortunate.

(to be continued)

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Re: Could Dark Matter Possibly Be . . .

Post by Nereid » Thu Nov 13, 2008 3:42 pm

Sputnick wrote:
=Nereid
Chris P will, no doubt, write his own response ... mine is as follows: what is the relationship between Kant's writing (on island universes) and science?
Page 125 from the oft and should be read book - "Island universes (Galaxies) "A concept contemplated by the great German philosopher Immanuel Kant as early as the 1700s." Of course others came before - the Greeks - the Persians - who knows who else. Why is that important. Why is a Philosopher not to be credit in astronomical science just because he's a philosopher and not an astronomer or an astrophysicist. He was correct about 'Island Universes' existing because until very recent time in modern history our galaxy was considered to be the universe. Hypotheses is part of science - Kant's ideas were a form of hypotheses, and if you, Nereid, are willing to say to Kant, 'Emmanuel, you are not scientific in your suggestion that (galaxies) Island Universes exist' then you have my blessing in your attempt to reach him.
In another forum, a long time ago, I wrote "ideas are cheap, anyone can have one".

While a history of (published, by rich, mostly white, men?) ideas is fascinating, I still don't get the connection between this and science; would you mind walking me through your views here, once again, please?

Let's take a hypothetical example: suppose we write a computer program to produce text strings in a clever way, involving terms like "energy", "universe", "dark matter", and so on. Let's also assume that the output of this program is sets of grammatically OK sentences. We then print these on a highly durable medium (stone tablets, perhaps) and put them into a time capsule. 10,000 years from now, the time capsule is opened, and the sentences translated into the then major languages. Suppose one set of sentences can be interpreted as closely resembling a wordy description of a key scientific discovery (a theory, perhaps) that lies 2,000 years in our (present) future. Suppose it's one sentence out of 10 million.

In this hypothetical example, in the Sputnick view of science, should our descendants credit the computer program with the discovery of this breakthrough, some 2,000 years before it was (independently) made? If not, in what key aspect would this differ from what Kant wrote, re "island universes"?

(Oh, and I think we should be having this discussion in a different thread)

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Methods for estimating the age of the universe

Post by Nereid » Thu Nov 13, 2008 4:04 pm

From BMAONE23's list, since Hubble, there seem to be four methods:

* estimate H(0) and derive the age from cosmological models (H(0) becomes an input to these models)

* estimate the age of old white dwarfs, the age of the universe is then something greater than this

* estimate the age of some old stars from the abundance of some radioisotopes and stellar evolution models, the age of the universe is then something greater than this

* estimate the age of some globular clusters from their HR diagrams and stellar evolution models, the age of the universe is then something greater than this.

The first method relies critically on the estimate of H(0), and just as critically on the details of the cosmological models it is used as an input in.

The second method has an unknown (the time from t = 0 to when the oldest white dwarf was formed) which can be constrained using cosmological models; the critical dependence, however, is on models of white dwarf stars.

The third and fourth methods have the same kind of unknown as the second; the critical dependence is stellar evolution models.

All methods have uncertainties, of several kinds, a common feature of all experimental and observational science. No surprise then for one to learn that astronomers spend enormous effort to identify uncertainties and constrain their values; no surprise either for one to learn that in the ~century-long history of observational cosmology there have been some surprises.

However, an informed reading of the history of estimates produced by the four methods I listed clearly shows Sputnick's comment^ to be ridiculous in the extreme. Perhaps it comes from an uncritical reading of certain crackpot material?

But maybe I'm wrong (I freely admit that I have been wrong in the past, and will certainly be wrong again in the future). Let's see Sputnick back up his inflammatory remarks, starting with a compilation of the key papers.

^ "The supposed age of the Big Bang universe has been changed every time a new 'measurement' of the age of galaxies near and far are made that conflict with the estimated age of the universe just before the new discoveries are made." (emphasis added)

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Re: Could Dark Matter Possibly Be . . .

Post by Sputnick » Thu Nov 13, 2008 4:56 pm

Chris Peterson wrote:
Sputnick wrote:
Chris Peterson wrote:Okay, I probably should have phrased that differently. No point of philosophy has ever been proven right. And philosophers, arguing philosophy, can only argue about opinions.
Well, I guess Einstein was simply wrong when he said it was time for Physicists to become Philosophers as a way of assisting their research.(?)
If man were made to fly he wouldn't need alcohol .. lots and lots and lots of alcohol to get through the furors while maintaining the fervors.

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Re: Methods for estimating the age of the universe

Post by Sputnick » Thu Nov 13, 2008 5:00 pm

Nereid wrote:
But maybe I'm wrong (I freely admit that I have been wrong in the past, and will certainly be wrong again in the future). Let's see Sputnick back up his inflammatory remarks, starting with a compilation of the key papers.

^ "The supposed age of the Big Bang universe has been changed every time a new 'measurement' of the age of galaxies near and far are made that conflict with the estimated age of the universe just before the new discoveries are made." (emphasis added)
I can fudge as easily as people with PHDs.
If man were made to fly he wouldn't need alcohol .. lots and lots and lots of alcohol to get through the furors while maintaining the fervors.

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Re: Methods for estimating the age of the universe

Post by Nereid » Thu Nov 13, 2008 6:11 pm

Sputnick wrote:
Nereid wrote:
But maybe I'm wrong (I freely admit that I have been wrong in the past, and will certainly be wrong again in the future). Let's see Sputnick back up his inflammatory remarks, starting with a compilation of the key papers.

^ "The supposed age of the Big Bang universe has been changed every time a new 'measurement' of the age of galaxies near and far are made that conflict with the estimated age of the universe just before the new discoveries are made." (emphasis added)
I can fudge as easily as people with PHDs.
You can?

When may readers expect to see the first post presenting support for your inflammatory remarks? A post which, I hope, will outline the scope of that support, summarise the nature of that support and key arguments, and make a firm commitment to providing references to peer-reviewed papers published in relevant journals as the primary sources of your case.

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Re: Methods for estimating the age of the universe

Post by Sputnick » Thu Nov 13, 2008 7:06 pm

Nereid wrote: When may readers expect to see the first post presenting support for your inflammatory remarks? A post which, I hope, will outline the scope of that support, summarise the nature of that support and key arguments, and make a firm commitment to providing references to peer-reviewed papers published in relevant journals as the primary sources of your case.
When I'm good and ready! Which may be awhile, as the 'good' position remains elusive, and the 'ready' position would require considerable education which I do not have the means to attain. I hope, Nereid, I detect a little humour in your question?
If man were made to fly he wouldn't need alcohol .. lots and lots and lots of alcohol to get through the furors while maintaining the fervors.

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Re: Methods for estimating the age of the universe

Post by apodman » Thu Nov 13, 2008 7:27 pm

Sputnick wrote:... would require considerable education which I do not have the means to attain. I hope, Nereid, I detect a little humour in your question?
I hope I don't. Where I don't have the background, I don't participate and I don't delude myself that my uninformed participation would be of any value. Like Dirty Harry said, "A man has got to know his limitations." You claim you are open-minded while others are not. You claim you frequent the library, and I know you have internet access. Complain about the education that is out of your reach only after exhausting all the resources the library and internet have to offer with that open mind of yours. The information is there. Spend more time absorbing, less time radiating. Whiner.

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Re: Methods for estimating the age of the universe

Post by Sputnick » Thu Nov 13, 2008 7:44 pm

apodman wrote:Where I don't have the background, I don't participate and I don't delude myself that my uninformed participation would be of any value.
Intuition is valuable, Apodman .. because we all live in this world, we all gain knowledge in our subconscious which springs out as intuition, and intuitions spring from other sources. I think I contributed huge value with the one paragraph from Einstein .. of course, because it comes from the 'other side' of the Big Bang .. the paragraph is not considered as valuable as if it had come from the, you know, the 'other side' of the Big Bang.
Experts in astronomy and physics have become blinded by their 'knowledge' .. that is hugely evident in the book I just read, and which I recommend you read.
Like Dirty Harry said, "A man has got to know his limitations."
Dirty Harry is not one of my role models .. I lean towards people like Grey Owl (Archie Belaney).
You claim you frequent the library, and I know you have internet access. Complain about the education that is out of your reach only after exhausting all the resources the library and internet have to offer with that open mind of yours. The information is there. Spend more time absorbing, less time radiating.
I spend considerable time at the library; but hiding a light under a bushel basket is not a way to share what I am learning.
Whiner.
You misspelled that.
If man were made to fly he wouldn't need alcohol .. lots and lots and lots of alcohol to get through the furors while maintaining the fervors.

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Re: Methods for estimating the age of the universe

Post by Nereid » Thu Nov 13, 2008 8:01 pm

Sputnick wrote:
Nereid wrote: When may readers expect to see the first post presenting support for your inflammatory remarks? A post which, I hope, will outline the scope of that support, summarise the nature of that support and key arguments, and make a firm commitment to providing references to peer-reviewed papers published in relevant journals as the primary sources of your case.
When I'm good and ready! Which may be awhile, as the 'good' position remains elusive, and the 'ready' position would require considerable education which I do not have the means to attain.
May I conclude, then, that there is little or no scientific merit to your remarks ... until you get around to demonstrating otherwise?

And that you will refrain from making comments that you (now) know will be inflammatory, and are (very likely) to be unsubstantiated with reliable, independently verified observational and experimental results (reported in relevant, peer-reviewed, journals)?
I hope, Nereid, I detect a little humour in your question?
No humour intended.

Our recent exchange of views, per our posts, captures well what is meant by this forum being a scientific one, focussed on astronomy; namely that questions and open comments (about astronomy) are welcome, but that repeated bald assertions - like this "The supposed age of the Big Bang universe has been changed every time a new 'measurement' of the age of galaxies near and far are made that conflict with the estimated age of the universe just before the new discoveries are made. In purely scientific terms those changes are called 'adaptive fudging'." - need to be retracted, or supported upon request, ultimately in a manner similar to what I outlined.

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Re: Methods for estimating the age of the universe

Post by apodman » Thu Nov 13, 2008 8:06 pm

Sputnick wrote:
Whiner.
You misspelled that.
Whino?

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Re: Methods for estimating the age of the universe

Post by apodman » Thu Nov 13, 2008 8:10 pm

Sputnick wrote:
A man has got to know his limitations.
hiding a light under a bushel basket is not a way to share what I am learning.
So instead you point a dim flashlight at the sun.

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Re: Methods for estimating the age of the universe

Post by Sputnick » Fri Nov 14, 2008 12:17 am

apodman wrote:
Sputnick wrote:
Whiner.
You misspelled that.
Whino?
Nereid - Help - Apeman is assaulting me outside of the protective boundaries of the forum.
If man were made to fly he wouldn't need alcohol .. lots and lots and lots of alcohol to get through the furors while maintaining the fervors.

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Re: Methods for estimating the age of the universe

Post by Sputnick » Fri Nov 14, 2008 12:25 am

Nereid wrote:
Our recent exchange of views, per our posts, captures well what is meant by this forum being a scientific one, focussed on astronomy; namely that questions and open comments (about astronomy) are welcome, but that repeated bald assertions - like this "The supposed age of the Big Bang universe has been changed every time a new 'measurement' of the age of galaxies near and far are made that conflict with the estimated age of the universe just before the new discoveries are made. In purely scientific terms those changes are called 'adaptive fudging'." - need to be retracted, or supported upon request, ultimately in a manner similar to what I outlined.
Okay - how about, 'The frequency of revised age for the universe based on new observations, and the non-speculative language used each time those ages are declared, persuade me that those changes will continue to occur for one reason only: that proof of Big Bang will continue to elude those saying they hold consensus; and those holding consensus will almost certainly never be swayed to consider alternative theories.
If man were made to fly he wouldn't need alcohol .. lots and lots and lots of alcohol to get through the furors while maintaining the fervors.

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Re: Methods for estimating the age of the universe

Post by Chris Peterson » Fri Nov 14, 2008 12:38 am

Sputnick wrote:Okay - how about, 'The frequency of revised age for the universe based on new observations, and the non-speculative language used each time those ages are declared, persuade me that those changes will continue to occur for one reason only: that proof of Big Bang will continue to elude those saying they hold consensus; and those holding consensus will almost certainly never be swayed to consider alternative theories.
Your position would make some sense if the successive estimates showed a pattern of divergence. However, that is not the case. The pattern over time has been that the estimated age of the Universe is converging on a single value, and the uncertainties are regularly reduced. This is occurring even as additional independent methods of estimation are used.

I'm not sure what you mean by "non-speculative language". All the estimates I've seen published for the age of the Universe are accompanied by error ranges. How is that "non-speculative"?

Of course, the BBT will never be proved, because that isn't possible. Evidence will likely continue to increase support for it, however. But maybe not.

The consensus is what it is. Nobody determines that; it is simply a recognition that a theory is accepted by a significant percentage of those expert in that field. Nobody thinks about whether they are "holding consensus", they simply decide what theories they accept as best.
Chris

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Re: Methods for estimating the age of the universe

Post by apodman » Fri Nov 14, 2008 1:01 am

Sputnick wrote:
apodman wrote:Whiner.
Sputnick wrote:You misspelled that.
Whino?
Nereid - Help - Apeman is assaulting me outside of the protective boundaries of the forum.

---

If man were made to fly he wouldn't need alcohol .. lots and lots and lots of alcohol to get through the furors while maintaining the fervors.
You provide the weapon, and in this case you also provided the invitation. And you beat us to death with wine, wine, wine and whine, whine, whine. What do you expect? Live by the sword ...

Some people consider this forum suitable matter for children to access on the internet. What social service does your signature line contribute to their education?

---

And don't you know that, in response to your hideous viewpoints, the vast scientific conspiracy is playing "good cop, bad cop, crazy cop" on you? Guess which one I am. It's much more entertaining in this day and age than burning at the stake. :P :wink:

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Re: Could Dark Matter Possibly Be . . .

Post by astrolabe » Fri Nov 14, 2008 1:36 am

Hello Sputnick,

Sorry, but I need to weigh in here. Please try to not forget this point because, after well over 200 posts in this thread, I still hear the same refrain in your dialog after all the attemp I have personally made to clear up the errant argument that you persist in using WRT the BBT. For the last time, it is a THEORY and theories CANNOT be PROVEN. No one is trying to prove the Big Bang-IT IS NOT A FACT!!!!! No one has claimed that it is a fact so why do you keep basing your perception on that falsehood? I need say nothing more on the matter than that.

I,m trying to not allow this idea of yours that the theory is some misguided power trip by mainstream science to mislead us poor dumb lemmings over the cliff of ignorance by injecting the public with some hairbrained scheme concocted in some think tank and blind us to other opinions or ideas.

Don,t worry- other theories can,t be proved either. if observation and fact point in a certain direction then that's the direction one goes in. People in NY will will wear black UNTIL something darker comes along and the scientific community will continually test the BB idea until something irrefutable steps up to the plate. I can almost guarrantee if something better comes along it will be replete with a lot of the data that scientists already have with a twist. They are looking at everything everyday with new tools, more number crunching brilliant minds and the best of all a knowledge base from deep in the past all the way up to this morning.

So......after 216 posts or so and a plethora of repetition from both sides I have yet to see resolution, e.i. read first paragraph. Don't close off. Include.
"Everything matters.....So may the facts be with you"-astrolabe

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Re: Could Dark Matter Possibly Be . . .

Post by harry » Fri Nov 14, 2008 3:40 am

G'day from the land of ozzzzzzzzzz


Reading the above the only thing that they have aged is the stage in a Sun's cycle of phases.

Everytime a star goes supernovae it may leave a core that acts as a gravity sink to be rejuvinated by attracting matter and thus form another solar envelope.

This cannot be used to calaculate the age of the universe.

How do you date a ultra dense core such as a black hole that is 20 billion Sun masses that is found in galaxy clusters?

Soon within the next 3 to 4 years they will see deep field images ove 14 Gyrs. I predict that they will see existing galaxies in various stage of evolution.

What than change the goal posts for the BBT?
Harry : Smile and live another day.

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Re: Could Dark Matter Possibly Be . . .

Post by Chris Peterson » Fri Nov 14, 2008 4:08 am

harry wrote:Everytime a star goes supernovae it may leave a core that acts as a gravity sink to be rejuvinated by attracting matter and thus form another solar envelope.
There's no evidence at all that the stellar core remaining after a supernova can attract material and form a new star. That's not how stars form.
Soon within the next 3 to 4 years they will see deep field images ove 14 Gyrs. I predict that they will see existing galaxies in various stage of evolution.
We currently have images of objects with at least z=7, or about 18 billion light years away. With radio we see the CMB, which is at something like 27 billion light years, IIRC. And we have been observing galaxies in different stages of evolution for a number of years now.
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Re: Could Dark Matter Possibly Be . . .

Post by apodman » Fri Nov 14, 2008 4:35 am

Chris Peterson wrote:We currently have images of objects with at least z=7, or about 18 billion light years away. With radio we see the CMB, which is at something like 27 billion light years, IIRC.
I'm sure there's a way to reconcile these numbers with a universe 13 to 14 billion years old, but at first glance they appear to be large, so I must ask: How do we observe something that is too far away for its light to have had time to reach us in the life of the universe? I thought the age of the universe (in years) was logically at least the distance of an observable object (in light-years).

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Re: Could Dark Matter Possibly Be . . .

Post by Chris Peterson » Fri Nov 14, 2008 5:00 am

apodman wrote:
Chris Peterson wrote:We currently have images of objects with at least z=7, or about 18 billion light years away. With radio we see the CMB, which is at something like 27 billion light years, IIRC.
I'm sure there's a way to reconcile these numbers with a universe 13 to 14 billion years old, but at first glance they appear to be large, so I must ask: How do we observe something that is too far away for its light to have had time to reach us in the life of the universe? I thought the age of the universe (in years) was logically at least the distance of an observable object (in light-years).
The distance from the Earth to the edge of the observable Universe is about 46 billion ly. Seems strange, but there's no conflict with the 13.7 billion year age of the Universe, because you have to take into consideration that the space containing distant objects has been moving away from us. The distance to the edge of the observable Universe is called the comoving distance. It might make it easier to visualize if you realize that we aren't talking about the light from an object 18 billion ly away having to cross that distance to reach us; when the light started towards us, the object was much closer. It has since gotten farther away, and the stretching space between is why we see a high redshift.
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Re: Could Dark Matter Possibly Be . . .

Post by BMAONE23 » Fri Nov 14, 2008 6:04 am

Chris,
I often heard the arguement that "When we look at an object that is 13g lys away, we are actually seeing the light that left that object 13g yrs ago" i.e. we see it as it appeared in the past. Now from what you are saying
Chris Peterson wrote:We currently have images of objects with at least z=7, or about 18 billion light years away. With radio we see the CMB, which is at something like 27 billion light years, IIRC.
For us to "See" these objects with a "Z" factor of 7 are you refering to Visible light?
If so then following the same principal as stated above: When we look at the light from an object that is 18g lys away, aren't we seeing it as it was 18g yrs ago? If so how can we observe the light from an object that was radiated 18g yrs ago in a universe that is only 13.7gy old?

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Re: Could Dark Matter Possibly Be . . .

Post by Chris Peterson » Fri Nov 14, 2008 6:27 am

BMAONE23 wrote:I often heard the arguement that "When we look at an object that is 13g lys away, we are actually seeing the light that left that object 13g yrs ago" i.e. we see it as it appeared in the past.
In the past, yes. But not 13 billion years ago.
For us to "See" these objects with a "Z" factor of 7 are you refering to Visible light?
Visible light, x-rays, radio, and other bands. I believe the most distant objects we can repeatably image are around z=7. We detect structure in the CMB which is much farther away, but you probably wouldn't use "object" for that.
If so then following the same principal as stated above: When we look at the light from an object that is 18g lys away, aren't we seeing it as it was 18g yrs ago? If so how can we observe the light from an object that was radiated 18g yrs ago in a universe that is only 13.7gy old?
No, when we see an object 18 billion ly distant, we are not seeing it as it was 18 billion years ago, because when the light that is reaching us left the object, that object was much closer. The light we see from the edge of the observable Universe, 46 billion ly distant, is from 13.7 billion years ago. (Actually, we don't see that far using EM, because the Universe wasn't transparent at first. Theoretically, we ought to be able to see to the very edge using something other than EM, like gravity waves.)
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Re: Could Dark Matter Possibly Be . . .

Post by BMAONE23 » Fri Nov 14, 2008 6:35 am

Sorry about the (dumb) questions but are you saying that when the object originally formed it was already 13.7 billion Light Years away from us and, over the last 13.7 billion years, as its light has been traveling toward us, expansion has forced it to move away from us an additional 5 billion light years? This is the only explanation that seems to allow for both to be correct, that the object is 18 billion light years away and we are just seeing its light from 13.7 billion years ago.
Last edited by BMAONE23 on Fri Nov 14, 2008 6:41 am, edited 1 time in total.