Searching for Dark Matter Particles Here on Earth

[Fraser]

Astronomers don't know what dark matter is, but they do know it takes up approximately 25% of the Universe. We can't see it, but we can measure the effect of its gravity on stars and galaxies. A powerful detector, deep underground in a mineshaft in Minnesota might be able to get to the bottom of the mystery. The Cryogenic Dark Matter Search II project will attempt to detect Weakly Interacting Massive Particles (aka WIMPS). These theoretical particles don't normally interact with matter, but the occasional rare collision might be detectable.

Read the full blog entry (http://www.universetoday.com/2006/11/29/searching-for-dark-matter-particles-here-on-earth/)

[searlesgold]

I have posted in the recent past regarding "Dark Matter!"
Yet, no one has replied >to me, as to what I think it is!

If there is an admittion that nobody knows what it is, then
the door is open to all of us to submit our opinion? DUH.
As long as we think it Must be something very mysterious,
ooooohhh,it must be very complex! Then quite possibly, the
"Brilliant Minds" of today will continue to have the answer Fly
right over the top of their heads!

Everything the human minds can see, then we can see everything
has some form of Color! (for those of you that try to hold up a
Defense that Black and White are not a color, move over!)
Only those of us that can comprehend Infinity, being both Time
and Distance will be able to see my view!

Since we agree that Infinity does exsist, then why don't we
consider that Black Matter is nothing more than the Color of...
Infinity! What we can see, the lit objects.....moons, stars on
top of stars, planets, Suns, etc., etc., are just bocking, the
Pure Beauty of INFINITY!

Infinity is the most powerfull thing known to "Modern Man" and
most Humans don't know of it, worse yet doesn't care about it!

Respectfully Yours,
Gary Searles

[Michael Noonan]

I have posted in the recent past regarding "Dark Matter!"
Yet, no one has replied >to me, as to what I think it is!

If there is an admittion that nobody knows what it is, then
the door is open to all of us to submit our opinion? DUH.
As long as we think it Must be something very mysterious,
ooooohhh,it must be very complex! Then quite possibly, the
"Brilliant Minds" of today will continue to have the answer Fly
right over the top of their heads!

Everything the human minds can see, then we can see everything
has some form of Color! (for those of you that try to hold up a
Defense that Black and White are not a color, move over!)
Only those of us that can comprehend Infinity, being both Time
and Distance will be able to see my view!

Since we agree that Infinity does exsist, then why don't we
consider that Black Matter is nothing more than the Color of...
Infinity! What we can see, the lit objects.....moons, stars on
top of stars, planets, Suns, etc., etc., are just bocking, the
Pure Beauty of INFINITY!

Infinity is the most powerfull thing known to "Modern Man" and
most Humans don't know of it, worse yet doesn't care about it!

Respectfully Yours,
Gary Searles



Hello Gary,

I would certainly like to know your theory. There must be a whole variety of answers. Currently I am trying to model a spinning structure of gravity. But the truth of it is there could be much better answers that have not been thought of yet.

Most of what I have learned has been through continued reading here and anything else I can find interesting on the internet.

Cheers

[Andromeda321]

Fermilab’s Dan Bauer is its project manager, and Dan Akerib from Case Western Reserve University is the deputy project manager. A team of 46 scientists at 13 institutions collaborates on the project.
This guy teaches me thermo. Nicest physicist you will ever meet.

[John Mendenhall]

Quoting the article: "Over the years, more and more evidence for dark matter has piled up. Although scientists don’t yet know what it is, they have a better idea of where it is and how much of it there should be. 'There’s very little wiggle room left for having different quantities,' Cabrera says. 'We’ve not seen anything that looks like an interesting signal to date,' he says."

This summarizes the situation on dark matter very concisely. The most important qualifier is missing, however. IF there is dark matter, and I will not argue against the fact that, if it exists, it solves the observational problems, then we know where it should be and how much is needed. The problem is that none, zero, zilch has been detected. Does this sound familiar? Has anybody looked for the ether wind lately and not found any? Are we missing something?

[01101001]

The problem is that [no dark matter], zero, zilch has been detected. Does this sound familiar? Has anybody looked for the ether wind lately and not found any? Are we missing something?

I dunno. Are we? Did we miss this: NASA Stars and Galaxies Feature: A Matter of Fact (http://www.nasa.gov/vision/universe/starsgalaxies/dark_matter_proven.html)


[...] a team of scientists working with NASA's Chandra X-ray Observatory has found direct evidence that dark matter is as real as the rings around Saturn.

The discovery cements dark matter's status as the biggest building block in the universe, while also putting to rest the nagging worries of many astronomers that they gambled wrong.
[...]
For the first time in history, astronomers caught dark matter at work.

"These results prove that dark matter exists," declared Clowe.

So there it is, bright as starlight: Dark matter matters, as a matter of fact.

The very article you quoted (http://www.universetoday.com/2006/11/29/searching-for-dark-matter-particles-here-on-earth/) reports that this way:


Scientists recently found direct evidence that dark matter exists by studying a distant galaxy cluster and observing different types of motion in luminous versus dark matter.

[John Mendenhall]

Yes, this is the claim that particularly irritates me. It is already well established that galaxies and galaxy clusters appear to have much more mass than we can see. It is nice that the Bullet galaxies have interacted to sweep themselves free of gas and thus allowed us to eliminate another possible source of mass. These galaxies have been cleaned out and they still appear to have too much mass. Their diagram of where the dark matter is is suppositional; if there is dark matter, this is where it has to be. They've got the cart before the horse. Their prediction is that the galaxies will still bend distant light as if they have more mass than is visible. Big deal. We already know that. It is unwise to promulgate the effect as the cause.

Hang on now, I'm going to agree with the dark matter school.

This leaves * at least * two possibilities, first that there is unseen dark matter surrounding the galaxies, or second that our understanding of gravity at very low levels is flawed. There may be others. I agree that dark matter is the most likely explanation, but folks, have some restraint. Until WIMPs or some such are actually detected, here on Earth, it would be courteous to at least say "if".

[01101001]

Their prediction is that the galaxies will still bend distant light as if they have more mass than is visible.

And now the evidence is that the galaxies will bend distant light as they have more mass than is visible.


Big deal.

Indeed it is.

[Blob]

These galaxies have been cleaned out and they still appear to have too much mass. Their diagram of where the dark matter is is suppositional; if there is dark matter, this is where it has to be. They've got the cart before the horse. Their prediction is that the galaxies will still bend distant light as if they have more mass than is visible. Big deal. We already know that. It is unwise to promulgate the effect as the cause....This leaves * at least * two possibilities, first that there is unseen dark matter surrounding the galaxies, or second that our understanding of gravity at very low levels is flawed

Hum,
you are not aware of all the facts.
One study of the bullet cluster clearly shows that there is a dark component that is gravitationally lensing background galaxies, and that it is separate from the optical component.
This therefore discounts a simple MOND explanation (ie “that our understanding of gravity at very low levels is flawed” does not apply).



Until WIMPs or some such are actually detected, here on Earth, it would be courteous to at least say "if".

No, based on what we know, it is not a question of `if`, the bottom line is that darkmatter is there.

[Fazor]

What is the other evidence of dark matter? Doesn't it partly have to do with the motion/rotation of galaxies? Or is it solely based on the light bending thing?

As far as the light, is it possible that light is bent as it passes through different gravitational fields, just as it is when it passes through objects of different density? for that matter, wouldn't the presence of a gravitational field have an impact on the density of sub-atomic particles in a given area of space? I dunno...most of this stuff is way over my head. Just curious.

[John Mendenhall]

One study of the bullet cluster clearly shows that there is a dark component that is gravitationally lensing background galaxies, and that it is separate from the optical component.

Reference? I seem to recall something about this also, but don't remember where.

Also, for Fazor, there is a good article in Wikipedia on dark matter.

[Blob]

Hum,
there are only a handful of landmark studies so far on darkmatter, IMHO.
The bullet cluster (1E0657-56) study (http://www.bautforum.com/showthread.php?t=45700) was announced in August, and it meant the end of MOND as a viable option.


“And some things that should not have been forgotten were lost” - Galadriel

[Jerry]

Dark Matter remains ~25% of the difference between what theory predicts, and what we observe.

The first postulate of Newton's Principle is that whatever we observe in the distance must be explanable using locally verifiable physical laws - we cannot assume distant stars burn dilithium crystals unless we can produce them locally. Dark stuff metrics violate this basic and necessary assumption. All we can say, if we do not see good evidence of similar behavior in our own domain (such as WIMPS), is that there is much that is not understood.

[antoniseb]

if we do not see good evidence of similar behavior in our own domain ...
Weren't you the person telling us about CREIL a couple of years ago?

[Tensor]

if we do not see good evidence of similar behavior in our own domain ...

Weren't you the person telling us about CREIL a couple of years ago?

Not to mention his claims on a variable g

[antoniseb]

OK, enough. I don't want to bash Jerry, but I did want to point out that his argument was a tough one to live by.

[Jerry]

Weren't you the person telling us about CREIL a couple of years ago?

Yes, and you are the person who pointed out to me CREIL runs into an unresolved problem in the microwave bandwidth. CREIL remains a potential mechanism for fairly broadband redshifting (but more likely, blurring) in certain environments, such as the extended photosphere of quasars, but I don't think it plays a significant cosmic role. Remember, CREIL is just the application of well-understood coherant electromagnetic phenomenon to broadband applications.

There is nothing wrong with being wrong. There is everything wrong with assuming the current consensus opinion is right.

[John Mendenhall]

There is nothing wrong with being wrong. There is everything wrong with assuming the current consensus opinion is right.

Loved it, Jerry. Do you think we could persuade the noted skeptic, the Amazing Randi, to rip into dark matter? Risky, Randi is a magician; he might come down on the side of illusion.

Seriously, I'd like nothing better than to have somebody detect WIMPs, but my gut feeling is that it's not going to happen.

Do you have some references for CREIL?

Thanks, John M.

[antoniseb]

Do you have some references for CREIL?
There is a CREIL thread (http://www.bautforum.com/showthread.php?t=23415&highlight=CREIL) in the ATM section. Jerry and other discuss it, and several of us create counter arguments. It's about 150 post long and has a few links to papers.

[John Mendenhall]

Thanks, Tony, you get a few days of quiet while I read through the ATM link.

[John Mendenhall]

Thanks, Tony, you get a few days of quiet while I read through the ATM link.

OK, I read through it. The idea is a little fuzzy. Too many special conditions required. Still, I recommend the thread. Thanks.