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Author Topic:   Dark matter a dying theory?
tesla
Member (Idle past 1593 days)
Posts: 1199
Joined: 12-22-2007


Message 1 of 113 (619075)
06-07-2011 11:15 PM


http://www.world-science.net/othernews/110415_darkmatter.htm
"Lack of success in dark-matter searches have fueled claims by some physicists that dark matter doesn’t exist at all."

keep your mind from this way of enquiry, for never will you show that not-being is
~parmenides

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Taz
Member (Idle past 3292 days)
Posts: 5069
From: Zerus
Joined: 07-18-2006


Message 2 of 113 (619076)
06-07-2011 11:31 PM
Reply to: Message 1 by tesla
06-07-2011 11:15 PM


Look, god knows what those scientists are really thinking. My problem with science writers is that they often don't know the details of what they are writing about.
The term dark matter refers to anything that exerts a gravitation force on the visible galaxy that's causing it to behavior more like a solid object than mostly empty space.
Looking for dark matter is like looking for a murderer. Suppose we find a woman stabbed to death. Whoever that killed her we will cal Mr. X. We got suspects A and B. Oops, neither A nor B turned out to be elsewhere when the woman was murdered.
To say that just because they can't find what dark matter is in a few tries then they doubt it exists is like saying Mr. X doesn't exist because A and B didn't turn out to be the murderer.
We know with absolute certainty that the galaxy is behaving like there are more mass in it than what we can see. It doesn't matter what dark matter is made of. It could be god for all I care. Nonetheless, it is there.
Edit.
I had a professor that had a hunch dark matter is made of an entirely different matter than then what we would call normal matter. And when I say different, I mean even the spins are different or there's no spin at all and it has no eletromagnetic charge it is simply impossible for us to detect it using conventional means.
Added by edit.
I just got reminded of the movie Analyze That. One of the witnesses testifying against the mob boss "committed suicide by stabbing himself 4 times in the back."
Look, if we know a woman was stabbed to death for times in the back, are we going to continue looking for Mr. X or are we going to assume a murderer involved is a dying theory because suspects A and B were found to be not it?
Edited by Taz, : No reason given.
Edited by Taz, : No reason given.

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slevesque
Member (Idle past 4640 days)
Posts: 1456
Joined: 05-14-2009


Message 3 of 113 (619077)
06-08-2011 12:00 AM
Reply to: Message 2 by Taz
06-07-2011 11:31 PM


Look, god knows what those scientists are really thinking. My problem with science writers is that they often don't know the details of what they are writing about.
The term dark matter refers to anything that exerts a gravitation force on the visible galaxy that's causing it to behavior more like a solid object than mostly empty space.
Looking for dark matter is like looking for a murderer. Suppose we find a woman stabbed to death. Whoever that killed her we will cal Mr. X. We got suspects A and B. Oops, neither A nor B turned out to be elsewhere when the woman was murdered.
To say that just because they can't find what dark matter is in a few tries then they doubt it exists is like saying Mr. X doesn't exist because A and B didn't turn out to be the murderer.
We know with absolute certainty that the galaxy is behaving like there are more mass in it than what we can see. It doesn't matter what dark matter is made of. It could be god for all I care. Nonetheless, it is there.
It is more complicated then that, unfortunately, we don't have any assurance it exists. The question becomes: when do you stop looking for vulcan and start thinking of alternative explanations ?
I had a professor that had a hunch dark matter is made of an entirely different matter than then what we would call normal matter. And when I say different, I mean even the spins are different or there's no spin at all and it has no eletromagnetic charge it is simply impossible for us to detect it using conventional means.
If I'm not mistaken, it cannot have electromagnetic charge because it only exerts gravitational effects. So it wasn't that big of a hunch (although it depends how long ago this was, since there was a time dark matter was thought to be regular matter)
Edited by slevesque, : No reason given.

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Taz
Member (Idle past 3292 days)
Posts: 5069
From: Zerus
Joined: 07-18-2006


Message 4 of 113 (619078)
06-08-2011 12:08 AM
Reply to: Message 3 by slevesque
06-08-2011 12:00 AM


slevesque writes:
It is more complicated then that, unfortunately, we don't have any assurance it exists. The question becomes: when do you stop looking for vulcan and start thinking of alternative explanations ?
Are you kidding me? Is this a joke? We haven't even sent a man to the nearest planet and you want us to give up already?
Again, you seem to be under the impression that "dark matter" refers to something specific. I assure, it is not. It is like saying "Mr. X murdered the woman." Mr. X refers to anyone who killed the woman. Mr. X is a place holder just like dark matter is a place holder.
If I'm not mistaken, it cannot have electromagnetic charge because it only exerts gravitational effects. So it wasn't that big of a hunch (although it depends how long ago this was, since there was a time dark matter was thought to be regular matter)
You don't understand. Everything we know of has an electromagnetic charge. Why the hell do you think we don't fall right through the earth surface and toward the center? All "normal" matter interact with electromagnetic force. That's why solid objects don't go through each other.
Edit.
If dark matter in fact turns out to be something that don't interact with electromagnetic force, then the only way to obtain a sample is by manipulating gravity. Unfortunately, for the moment it is beyond our capability.
Added by edit again.
Actually, technically speaking whatever dark matter is is the normal matter of the universe, since it makes up most of the total matter in the universe.
Edited by Taz, : No reason given.
Edited by Taz, : No reason given.

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slevesque
Member (Idle past 4640 days)
Posts: 1456
Joined: 05-14-2009


Message 5 of 113 (619079)
06-08-2011 12:20 AM
Reply to: Message 4 by Taz
06-08-2011 12:08 AM


Are you kidding me? Is this a joke? We haven't even sent a man to the nearest planet and you want us to give up already?
I have never suggested we give up. I have difficulty seeing where anything I said could be interpreted as such.
Again, you seem to be under the impression that "dark matter" refers to something specific. I assure, it is not. It is like saying "Mr. X murdered the woman." Mr. X refers to anyone who killed the woman. Mr. X is a place holder just like dark matter is a place holder.
I am under no such impression. I study physics and I have already been to a couple lectures on the subject and it was brought up multiple times in discussions with teachers and fellow students alike.
''Looking into alternatives'' and ''giving up'' are two very different things. My question is perfectly reasonable, and the vulcan analogy appropriate.
You don't understand. Everything we know of has an electromagnetic charge. Why the hell do you think we don't fall right through the earth surface and toward the center? All "normal" matter interact with electromagnetic force. That's why solid objects don't go through each other.
Yes, but unless anyone thought dark matter was baryonic matter, this is irrelevant.
Considering dark matter was undetectable, having the hunch that ''it didn't have an electromagnetic charge'' wasn't all that extraordinary of a hunch.
Edited by slevesque, : No reason given.

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Taz
Member (Idle past 3292 days)
Posts: 5069
From: Zerus
Joined: 07-18-2006


Message 6 of 113 (619080)
06-08-2011 1:06 AM
Reply to: Message 5 by slevesque
06-08-2011 12:20 AM


Ok, I'll take that.
I just have a problem with the OP suggesting that dark matter doesn't exist because of a failed attempt at finding it. Again, this is like saying there was no murderer after finding out suspects A and B both had an alibi even though a woman was stabbed to death 4 times in the back.

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PaulK
Member
Posts: 17822
Joined: 01-10-2003
Member Rating: 2.2


Message 7 of 113 (619081)
06-08-2011 1:36 AM
Reply to: Message 1 by tesla
06-07-2011 11:15 PM


If you bother to read the article you will see that it refers only to attempts to detect one possible form of dark matter on Earth. Even then it seems incomplete, not mentioning a possible detection in a Minnesota mine in 2009. In addition it must be noted that detection of these particles is extremely difficult, so the failure is not conclusive.
Also, the link to another part of the site indicates that the doubters are only a small group (and by my understanding they don't have a viable alternative to dark matter yet).
To sum up, we have a small problem for one admittedly popular view of dark matter, but the idea of dark matter itself is not in serious trouble at all.

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frako
Member (Idle past 306 days)
Posts: 2932
From: slovenija
Joined: 09-04-2010


Message 8 of 113 (619082)
06-08-2011 3:57 AM
Reply to: Message 1 by tesla
06-07-2011 11:15 PM


Well if scientists knew what they where looking fore they wouldn't conduct research.
All they know for sure is that there is more gravity required to make galaxies, to hold galaxies together then there is exerted by normal matter.

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cavediver
Member (Idle past 3643 days)
Posts: 4129
From: UK
Joined: 06-16-2005


Message 9 of 113 (619083)
06-08-2011 4:24 AM
Reply to: Message 3 by slevesque
06-08-2011 12:00 AM


The question becomes: when do you stop looking for vulcan and start thinking of alternative explanations ?
You are on a one-way trip to cranks-ville with this thinking. I'd get that out of your system now. If you think for one second that the cosmology world has not seriously looked at alternative explanations, you're an idiot.
These are just the papers I found that contain the words "alternative", "dark", and "matter" in the title...
We have high-confidence that dark-matter is real. High-confidence does not mean "this is the truth and we cannot possibly be wrong".

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frako
Member (Idle past 306 days)
Posts: 2932
From: slovenija
Joined: 09-04-2010


Message 10 of 113 (619084)
06-08-2011 4:47 AM
Reply to: Message 1 by tesla
06-07-2011 11:15 PM


One thing is bothering me though the artile says in 100 days no wimps found, but the way i understand it those guys looking for wimps do not look at the data logger for a whole year of waiting.

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PaulK
Member
Posts: 17822
Joined: 01-10-2003
Member Rating: 2.2


Message 11 of 113 (619085)
06-08-2011 8:06 AM
Reply to: Message 1 by tesla
06-07-2011 11:15 PM


Not so fast....
Since then, one more experiment has reported positive results, and another appears to be on the verge of doing so. And it seems that these results are consistent with an earlier report. More here

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Admin
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Posts: 12998
From: EvC Forum
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Member Rating: 2.3


Message 12 of 113 (619087)
06-08-2011 8:11 AM


Thread Copied from Coffee House Forum
Thread copied here from the Dark matter a dying theory? thread in the Coffee House forum.

  
Percy
Member
Posts: 22392
From: New Hampshire
Joined: 12-23-2000
Member Rating: 5.3


Message 13 of 113 (619089)
06-08-2011 8:25 AM
Reply to: Message 3 by slevesque
06-08-2011 12:00 AM


slevesque writes:
The question becomes: when do you stop looking for vulcan and start thinking of alternative explanations?
Yeah, you're right, even though a Nobel awaits the team that uncovers the nature of what we currently call dark matter, scientists march in lock step to their preconceptions and refuse to think outside the box. Over the past decade the articles I've read have described scientists who are confining themselves to only the most pedestrian of possibilities.
  • Yet undiscovered forms of matter? How boring is that!
  • Mini-black holes created during the big bang? Yawn.
  • Modified laws of physics? Snore.
  • Effects of extra dimensions? Soporific (look it up).
--Percy

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NoNukes
Inactive Member


Message 14 of 113 (619093)
06-08-2011 9:46 AM
Reply to: Message 5 by slevesque
06-08-2011 12:20 AM


slevesque writes:
''Looking into alternatives'' and ''giving up'' are two very different things. My question is perfectly reasonable, and the vulcan analogy appropriate.
I think the analogy is apt, but perhaps strained. The hypothetical Vulcan was merely difficult to detect. But there was no belief that it would be impossible to detect.
It may well be that dark matter is impossible to detect other than through its gravitational effect. There may never be anything other than highly circumstantial evidence for dark matter. Unlike the case of Vulcan, every failure to detect dark matter may mean simply dropping one particular dark matter hypothesis.

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tesla
Member (Idle past 1593 days)
Posts: 1199
Joined: 12-22-2007


Message 15 of 113 (619116)
06-08-2011 3:14 PM
Reply to: Message 11 by PaulK
06-08-2011 8:06 AM


Re: Not so fast....
You know, It could be a problem with the math.
Let's examine this posibility as well:
Lat's say a spinning mass is off balance. take a beach ball, and in the center attach a metal core, one half iron, the other half aluminum. In a free spin (in space), will it travel?
Edited by tesla, : elaboration

keep your mind from this way of enquiry, for never will you show that not-being is
~parmenides

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Replies to this message:
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 Message 17 by Taq, posted 06-08-2011 4:54 PM tesla has replied

  
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