Doubts about the dark side

[HysteryDiagnosis]

http://www.dur.ac.uk/news/newsitem/?itemno=10230


News

Durham astronomers’ doubts about the “Dark Side”
(16 June 2010)

New research by astronomers at Durham University suggests conventional wisdom about the content of the Universe may be wrong.

Graduate student Utane Sawangwit and Professor Tom Shanks, in Durham's Department of Physics, looked at observations from the Wilkinson Microwave Anisotropy Probe (WMAP) satellite to study the remnant heat from the Big Bang.

The two scientists found evidence that the errors in its data may be much larger than previously thought, which in turn makes the standard model of the Universe open to question.

They published their results in a letter to the journal Monthly Notices of the Royal Astronomical Society.

Launched in 2001, WMAP measures differences in Cosmic Microwave Background (CMB) radiation, the residual heat of the Big Bang that fills the Universe and appears over the whole of the sky.

[ithinkmyliverhurts]

1. There is no dark side of the moon really. Matter of fact it's all dark.

All that you touch
All that you see
All that you taste
All you feel.
All that you love
All that you hate
All you distrust
All you save.
All that you give
All that you deal
All that you buy,
beg, borrow or steal.
All you create
All you destroy
All that you do
All that you say.
All that you eat
And everyone you meet
All that you slight
And everyone you fight.
All that is now
All that is gone
All that's to come
and everything under the sun is in tune
but the sun is eclipsed by the moon.

"There is no dark side of the moon really. Matter of fact it's all dark."

[AnnieBW]

13. Beat me to it!

N/T

[HysteryDiagnosis]

15. If your liver hurts.... read on alpha lipoic acid, milk thistle and

dandelion root tea.

[greytdemocrat]

2. Sounds interesting.

"Errors in its data"...sounds like...Global Warming.

[HysteryDiagnosis]

3. Has to do with gravitational forces being the dominant force in the

cosmos vs electromagnetic forces. Some do some don't.

ON EDIT TO ADD: I'm just sayin'...

[greytdemocrat]

4. I understand.

The piece speaks about errors. They happen.

[HysteryDiagnosis]

5. It is said that a strong theory or even assumption should not

continually produce "surprises", modern cosmology is rife with them. It shouldn't be.

[greytdemocrat]

6. Well,

What would the universe be if it wasn't full of surprises?? I'm glad it is.

[phasma ex machina]

7. "Having a model dependent on as yet undetected exotic particles that make up dark matter and the

completely mysterious dark energy leaves many scientists feeling uncomfortable."

OTOH mysteries leave me feeling intrigued.

[HysteryDiagnosis]

8. When I get mysterified I consider other explanations for things

... and I pay the price for it. Oh bother.


http://www.thunderbolts.info/tpod/00current.htm
Astronomers came up with a dark (or undetectable) form of matter when they noticed stars on the edge of a spiral galaxy orbiting its nucleus with the same angular speed as stars closer to its center. As Newtonian mechanics insists, stars farther away from the center should be moving more slowly, so astronomers assumed dark matter was imparting extra velocity to them.Investigators have also tried for years to reconcile the amount of mass in the Universe with how fast it is expanding. Their only recourse has been to invent the existence of another undetectable force, “dark energy.”

As long ago as 2007, for example, serious reconsideration of dark matter theory was already published. Consensus astronomy presupposes dark matter organizing galactic structure. Dark matter (as well as dark energy) are thought to be necessary mathematical constructs in the astronomical community, because in their minds gravity is the sine qua non of all forces that govern galactic motion.

[TheKentuckian]

11. It should make them uneasy because their model is based in large part on

pure speculation, a device to make the numbers work with the observations.

It's a rational device but it could be totally off base.

[girl gone mad]

10. It's not as bad as that.

We have two fundamental theories that explain and predict with certainty. There are only a few things that we don't understand very well, gravitational weakness, for instance, and some of the confusion is rooted in the more abstract thinking that has dominated the field in the last two decades. These surprises are what we hope for because they help us tweak theories or simply throw them in the trash heap. Often, they cause us to rediscover previously abandoned theories.

Many of us are hoping that LHC results provide the shock of the century because current models leave much to be desired. Speaking for myself, there are a few ideas I would like to see tossed.

[Confusious]

12. few ideas I would like to see tossed

like what?

[tridim]

9. Wrong or not, particle physics is getting very exciting lately

I just saw a show on the Science channel that mentioned the orbits of two central black holes in colliding galaxies is analogous to the electron cloud around a atomic nucleus. The black hole orbits appear to jump energy levels just like an electron in an atom!

That might be common knowledge in the theoretical physics community, but it blew my mind.

[Hawkowl]

14. !

Massive black holes do funny things to time.

[hayu_lol]

16. Buzz word in the entire piece is...

"MAY have errors."

[HysteryDiagnosis]

17. Ah yes.... the may defense... I've seen it used in other

galaxies... but this one not so much.

Dark Matter Hiding in the Margins

http://www.thunderbolts.info/tpod/2009/arch09/090827margins.htm
A recently published paper in the Journal of Physics A by Adler (2008) calculates the maximum amount of cold dark matter that must be present in the space between the Laser Geodynamics Satellites (LAGEOS) and the Moon’s orbit. Adler asserts that there is at most the equivalent to 4 x 10^-9 of Earth’s mass of dark matter in that volume (2.4 x 10^16 kilograms).

This scientific journal article was reported on the Scientific American and the American Scientist websites, among others. Unfortunately, the writers and editors seem not to have read the original paper and were more concerned with sensational headlines about dark matter than responsible science reporting. Still worse, the editor of the Journal of Physics A didn’t seem to pay much attention to the paper.

What Adler does is deceptively straightforward. He uses published measurements for the gravitational parameter (GM in units of kg^3/s^2, the product of the gravitational constant G and the object’s mass) for the Earth alone, the Moon alone, and the Earth and Moon combined. After subtracting the values for the Earth alone and the Moon alone from the value of the two combined, what is left must be dark matter.

Adler's value for the combined GM parameter is 403503.2357 ± 0.0014. His value for the Earth alone is 398600.4356 ± 0.0008, and his value for the Moon alone is 4902.8000 ± 0.0003. Each of these gravitational parameters is derived using a different method with different sets of assumptions, and are then "tweaked" in different ways (with implicit assumptions) before the final calculations. In the end, Adler finds the GM for dark matter to be 0.0001±0.0016. By dividing this value by the GM for the Earth, the result is a ratio of (0.3 ± 4) x 10^-9. Based on that result, he asserts that there must be a mass of dark matter less than 4 x 10^-9 times that of the Earth in that volume of space (G assumed to be a constant).