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Fraser
2005-May-18, 05:37 PM
SUMMARY: Cosmologists from Princeton are working on new tests that could help to explain the nature of "dark energy", a mysterious force accelerating the expansion of the Universe. It could be an unknown form of energy, or it could be that Einstein's General Theory of Relativity breaks down at very large scales. The researchers will track the rate at which galaxy clusters have grown in time. If this growth is consistent, it'll mean that dark energy is at work; otherwise, it could mean problems with Einstein's predictions.

View full article (http://www.universetoday.com/am/publish/dark_energy_breakdown.html)

What do you think about this story? Post your comments below.

om@umr.edu
2005-May-18, 06:27 PM
This is an interesting idea, Fraser.

But this issue may not rank very high with the public.

The problem is, we do not even know if Dark Energy is real.

"We don't know," comments Professor David Spergel from Princeton. "It could be a whole new form of energy or the observational signature of the failure of Einstein's theory of General Relativity. Either way, its existence will have profound impact on our understanding of space and time. Our goal is to be able to distinguish the two cases."

The public would probably rather hear scientists address issues that influence life here on Earth.

E.g., reasons for the Sun's variability, earthquakes, the origin of the solar cycle, changes in Earth's climate, the origin of solar magnetic fields, solar eruptions, etc.

With kind regards,

Oliver
http://www.umr.edu/~om

antoniseb
2005-May-18, 06:50 PM
Originally posted by om@umr.edu@May 18 2005, 06:27 PM
The public would probably rather hear scientists address issues that influence life here on Earth.
Are you saying that any astronomy work being done unrelated to solar research is something we shouldn't do based on your perception of what the broader public would want?

Personally, I like that Universe Today covers a wide variety of topics in every area of Astronomy research, and would be sad if it started restricting itself to only articles about the Sun, Earthquakes, and the Weather.

dmccarroll
2005-May-18, 07:07 PM
As I have stated before. There may be a chink in Einstein's armor. I realize that we have based most of our research in cosmology based on the theories put forth by the General Relativity Theory that was written at the beginning of the last century. But how long did our predecessors base their ideas on the theories and laws laid down by Newton? Planke?, Copernicus? The time may be here for, lets say, an expansion of Einstein's theories. Rather than miring ourselves in the work completed by others, let's see if we can expand our horizons and come up with new, exciting discoveries, albeit tempered by healty skepticism, and maybe, just maybe, lauch ourselves into the next era of discovery. I think that the observations reported in this article are just the beginning of perhaps a new understanding of the cosmological picture. I'm looking forward to seeing where this goes and am excited that there are those who are willing to say "Maybe Einstein didn't have a total understanding of it all".

antoniseb
2005-May-18, 07:24 PM
Originally posted by dmccarroll@May 18 2005, 07:07 PM
let's see if we can expand our horizons and come up with new, exciting discoveries, albeit tempered by healty skepticism, and maybe, just maybe, lauch ourselves into the next era of discovery.
I think that the overall idea is that we will continue doing what we've been doing, that is, increasing the precision, accuracy, scope, and complexity of our observations. This would have happened even without your suggestion that we come up with new discoveries (but thanks for spurring us on... you can help).

At some point, we will discover things that show General Relativity, and Quantum Mechanics to both be good macroscopic approximations for medium sized spaces that both break down, or need refinement in extreme scales. No one questions that. However, there is no NEED to get to such depth of observation faster because of some burden that Einstein has given us. We are simply pressing ahead, and refining things as we go.

om@umr.edu
2005-May-18, 08:30 PM
Originally posted by antoniseb@May 18 2005, 06:50 PM
Personally, I like that Universe Today covers a wide variety of topics in every area of Astronomy research, and would be sad if it started restricting itself to only articles about the Sun, Earthquakes, and the Weather.
So do I, Anton.

But I think astronomy and astrophysics would be well served to pay more attention to the star next door.

Our very lives depend on that one.

With kind regards,

Oliver
http://www.umr.edu/~om

antoniseb
2005-May-18, 08:39 PM
Originally posted by om@umr.edu@May 18 2005, 08:30 PM
But I think astronomy and astrophysics would be well served to pay more attention to the star next door.
There's a great deal of funding and effort that go into monitoring and understanding the Sun. I'm not sure how you think we could reasonably spend more? Look at all the spaceprobes that are strictly for observing different aspects of the Sun's output. Look at all the Earth based efforts including the neutrino observatories. You write like we are ignoring the Sun, but clearly we aren't.

Fraser
2005-May-18, 08:40 PM
I probably have 2-3x as many stories about the Sun as I do about Dark Energy.

om@umr.edu
2005-May-18, 10:00 PM
Originally posted by antoniseb@May 18 2005, 08:39 PM
You write like we are ignoring the Sun, but clearly we aren't.
I certainly do not want to discourage astronomers and astrophysicists from other studies.

But the solar cycle, solar magnetic fields, and solar eruptions - processes that directly influence the lives of everyone on Earth - are frankly not explained by the model of a Hydrogen-filled Sun, e.g., these quotes from Ulysses Spacecraft Findings (http://www.spaceref.com/news/viewpr.html?pid=13022)

"Data from Ulysses show that the solar wind originates in holes in the sun's corona, and the speed of the solar wind varies inversely with coronal temperature.

"This was completely unexpected," said Lanzerotti. "Theorists had predicted the opposite. Now all models of the sun and the solar wind will have to explain this observation."

Another surprising finding based on Ulysses' data is that the sun's magnetic field originates from a magnet that seems to be perpendicular to the sun's axis of rotation (instead of being parallel to it, as is the case with Earth).

"At solar maximum, the sun's polar cap magnetic fields reverse direction or sign," said Edward Smith of NASA's Jet Propulsion Lab at the California Institute of Technology, who is the US project scientist for the Ulysses mission. "Inward fields become outward and vice versa. Ulysses observations show that during this reversal, the Sun's magnetic poles are located near the solar equator instead of in the polar caps."

The sun has a powerful magnetic field . . . . It is thought that solar activity is strongly related to changes in the sun's magnetic field."

"We knew that the sun's magnetic field was dynamic and variable," said Lanzerotti. "But this shows that we still have a lot of understanding to do. No one really knows how it is formed and why it changes as it does."

Given this state of solar science, I think it would be wise for astronomers and astrophysicists to decipher the star next door first, and then work their way out from there to the far reaches of the universe.

That is my opinion. Of course, I admit to a strong bias.

With kind regards,

Oliver
http://www.umr.edu/~om

wstevenbrown
2005-May-18, 10:32 PM
Oliver:

Of course it's difficult to model. Most of the magnets we have direct experience of do not have thermonuclear reactions with their messy old noise (and associated inconvenient temperatures) in their innards. Don't throw the baby out with the bath. S

isferno
2005-May-19, 06:20 PM
Originally posted by om@umr.edu@May 19 2005, 12:00 AM
Given this state of solar science, I think it would be wise for astronomers and astrophysicists to decipher the star next door first, and then work their way out from there to the far reaches of the universe.

That is my opinion. Of course, I admit to a strong bias.
[/URL]
Hello Oliver,

Since you indirectly refer to your IRON-SUN model, may I state that your basis for this model originates from the observations of Supernova, which I assume, didn't happen within our solar system?

Below a simple childish trick to show you what single mindedness might do if you observe only one line of science.







http://home.tiscali.nl/sfictie/colors.gif

Only two colors are used!

Sp1ke
2005-May-20, 08:46 AM
Excellent illustration, Isferno. It still took me a while to convince myself that there were only two colours, even though you said there were.

Personally I don't worry about claims that the scientific process is biased and blinkered. Every new observation will either fit neatly into current theory or it will appear to be an exception. And the exceptions test the theory (not exceptions prove the theory). A theory will be modified to cater for the exception, or it will be replaced by a theory that better fits the new and existing data.

Dark Energy is a good example of this working in practice. The big bang theory appears to be a good explanation for observations. But it's not perfect and does appear to require dark energy, inflation etc. But I don't think scientists around the world are ignoring observations that conflict with the theory - they see whether the theory can be adapted to cope with what appear to be exceptions or whether there is another theory that fits the facts better. And at some point, we'll either have a modified ("better") BBT or another theory will replace it.

The main thing is not to panic every time someone sees what looks like a contradiction. We would not progress as quickly if generations of science were thrown away immediately one datum did not fit the models. A certain amount of conservatism keeps things on an even keel so I think it should be quite difficult to overturn the mainstream theory - "an exceptional proposal requires exceptional proof".

isferno
2005-May-20, 07:43 PM
Hey Spike,

Thanks! :D

Though everybody is in some way or another biased. For example, if I read your post, I noticed that with you "fear" is hooked up with "biased" (with the statement: "personally, I don't worry". Who did?).
With Dr Manuel, it's his over-enthousiastm for his lifework. Others did their homework too on the subject. Its time for him to compare notes. Not just to present his findings and search through other peoples notes for confirmation of his theory.

Duane
2005-May-20, 07:51 PM
I agree with you there isferno. Dr O has presented his "best case" already, and was duly challenged to the point where his claims became redundant repeats. While the pursuit of evidence in support of one's claims is admirable, it is hypocracy to carefully pick though research to isolate references that might provide support, while ignoring the overall findings in those same papers that do not support your thesis.

nnunn
2005-May-21, 05:47 AM
Oliver does make an interesting point about how poorly our numerical models deal with non-trivial, large-scale magnetic phenomena. And given that so many foundational concepts in astrophysics, hence cosmology, involve assumptions about the behavior of magnetic fields, a deeper understanding of flipping fields in our local star would not hurt.
Nigel

om@umr.edu
2005-May-21, 01:09 PM
You are exactly right, Nigal.

See today's news item about NASA's discovery that Deep Seated Magnetic Fields Cause the Solar Wind and Solar Eruptions (http://www.universetoday.com/am/publish/predicting_solar_wind.html?2052005)

These deep solar magnetic fields guide 50,000,000,000,000 metric tons of Hydrogen to the surface of the Sun each year, where it is expelled into space.

Antoine Lavoisier, the "father of Chemistry" coined the name Hydrogen for the gas pouring from the top of a beaker when heat is produced as zinc reacts with sulfuric acid:

Zinc + Sulfuric Acid ->
-> Zinc Sulfate + Hydrogen Gas

It is interesting that Hydrogen also pours from the top of the Sun as heat is produced there.

With kind regards,

Oliver
http://www.umr.edu/~om

isferno
2005-May-22, 04:59 PM
To stay on topic now:

I have no clue what they mean by 5th Dimension. Below is the closest thing as I understand it.

http://home.tiscali.nl/sfictie/5d.gif

In case1:
relative Linear distances and distribution with hyperbolic deviation

In case2:
relative Hyperbolic distances with linear distribution and zero deviation.

Which is it?