Physicists Resurrect an Old, Strange Dark Matter Theory 138
New submitter rossgneumann writes: Dark matter might not be nearly as exotic as most theories suggest. Instead, it could be macroscopic clumps of material formed from common particles already found within the Standard Model of particle physics. This argument comes courtesy of physicists at Case Western University (PDF). Dark matter is usually thought of in terms of exotic, so-far undiscovered particles. The leading candidates are known as weakly interacting massive particles, or WIMPs. But the Case Western theory suggests that there are no dark matter particles, at least none that exist outside of current knowledge. Instead, there are baseball-sized clumps of "regular" matter formed from unexpected combinations of Standard Model particles.
Strange? (Score:3)
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Amazing that they haven't already ruled out common particles as a source of dark-matter anomalies in the galaxy rotation curves... you'd figure that would be the first suspect analyzed?
Re:Strange? (Score:5, Informative)
Common particles tend to absorb EMR if they're cold, or emit EMR if they're warm.
Re:Strange? (Score:5, Insightful)
Amazing that they haven't already ruled out common particles as a source of dark-matter anomalies in the galaxy rotation curves... you'd figure that would be the first suspect analyzed?
You can't rule them out from galaxy rotation, that's why MACHOs were just as viable as WIMPs early on, and none of those hypotheses were particularly credible.
But the important data is the CMBR data, which tells us, to 2 significant figures, the ratio of dark matter (does not interact with photons even at very high energy densities) to normal matter - more than 5:1 dark. It also tells us that the dark matter must be "cool" (not moving at or near the speed of light).
At this point, any hypothesis that doesn't explain galaxy rotation and the CMBR data and the gravitational lensing from galaxy-sized objects we can't see and make some useful prediction that the current WIMP models don't is just a crackpot idea: junk science.
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Here's a crackpot idea for you: what if space came pre-"dimpled" at a large scale (in other words: gravity being a property of both space and mass, not just mass), and the galaxies we see are just the result of whatever loose stuff fell into the gravity wells that were already there. Then the massless lenses are simply wells that stars haven't fallen into yet.
Re:Strange? (Score:4, Funny)
OOOOOO.. Quantum Buuuuuuuuuuuuuuuuuurrrrrrrrrrrrrrrrrrrrrnnnnnnnnnnnnnnnnnnnn
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No, the "Your-Mom" hypothesis for gravitational discrepancy in the universe has already been debated at length by many of the world's foremost astrophysicists.
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And the CMBR data? Fail.
Every problem has a simple, easy to understand, wrong answer.
Re:Strange? (Score:4, Insightful)
Sure, when it's actually done, then it's worth the attention of others. But the internet is full of easy explanations (if you ignore half the data) for just about everything in cosmology. And WIMPs mat actually be wrong. But any alternative needs to be better: this isn't politics, we can't just ignore inconvenient data.
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It's mathematical wankery based on exactly NOTHING.
So why not respond with a mathematically precise criticism, instead of just listing off topics that could easily be confused for someone who just reads pop-sci garbage? As much group-think as Slashdot can have, putting actual substance in your post can bypass that easy enough. Otherwise, everyone will just assume you have no idea what you're talking about until proven otherwise.
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If something is unfalsifiable, it may be brilliant, witty and elegant, but it's not a scientific theory: it's a good concept for a sci fi novel.
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Well, it's clearly not a strange [wikipedia.org] theory, but it is unusual in that it actually attempts to find a solution assuming both the known matter and the known models of gravity. This should be relatively easy to test (compared to the other wild guesses).
Re:Strange? (Score:4, Insightful)
Or it's exotic that this matter is so strange.
I'm afraid most of us can't really follow what physicists mean by 'exotic' or 'strange' any more.
Does it taste minty?
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Or maybe some of the particles include strange quarks? [wikipedia.org]
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So it's strange that this matter may not be exotic?
It's also got the density of a neutron star and is a fluid so... Good luck
the reason you can't find that mass (Score:1)
is that it's in boxes behind stuff. this is a theory that all these PhDs, going college to college to advanced study for a decade or so, should sign on to in a flash. I'll take my Nobel in person, thanks.
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Its strange that the matter is largely made of Strange quarks, which are technically not exotic, even though we don't see such objects in everyday life.
Re:Strange? (Score:4, Funny)
"One strange, old trick helped me lose 165 LBs"
=
"Physicists Resurrect an Old, Strange Dark Matter Theory"
Re:Strange? (Score:5, Informative)
So they would look like baseball or basketball-sized spheres of matter that is even denser than neutronium. It won't be 'dark' - strange particles can interact with photons just fine. These clamps will move at 'galactic' speeds (~100 km/sec) but not at relativistic speeds. They'd be able to punch through the galactic dust clouds like a bullet through a sheet of paper and given the general density of the matter in a galaxies (i.e. 'almost perfect vacuum') the strange clumps are expected to be captured by stars in significant quantities only on the scale of tens of billions of years.
Another interesting feature is their "surface tension" barrier. The strange clumps can NOT accrete normal matter, regular nuclei would simply bounce off the border between the vacuum and the strange matter. This barrier can be pierced by sufficiently energetic individual particles or by slamming into dense matter (i.e. a planet).
The probability of such clump hitting the Earth is about once in every 1000 years. It'll punch through the atmosphere and explode somewhere deep in the crust or in the mantle. From the outside it'd look like a large earthquake.
Re:Strange? (Score:4, Interesting)
The issue I have with this theory is, in the 4,000,000,000 years that Earth has been around, wouldn't quite a lot of this 'matter' built up in the crust and core? Where is it at? Sinking deep in to the crust?
Re:Strange? (Score:5, Informative)
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Once the surface tension barrier is breached, the clump explodes in a huge nuclear explosion. Strange matter particles then simply decay and become regular hadrons and form regular nuclei. However, it's also possible that some clumps sank to the core if the collision conditions were just right and surface tension barrier is strong enough.
In that case wouldn't we see a varying degree of dark/strange/missing versus normal matter over time and thus have more missing matter in older galaxies that were farther away and be able to test for that?
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Neutron-star density, as in one baseball of the stuff weights as much as 1000 Mount Everests. This stuff would fly through the Earth without too much resistance, even without slowing down too much.
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Those mica specimens go back to around 500 million years. You can go back further, but the mass constraints change because thermal effects in the rocks slowly heal older crystal dislocations, erasing the record like on
In laymen's terms... (Score:4, Insightful)
Excuse the oversimplification here but....
What I'm getting is, if they take a bunch of particles together in the right combination, then they no longer emit or react to photons? A) huh? B) so invisibility cloak anyone?
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Outlook uncertain. Try again later.
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B) so invisibility cloak anyone?
It'd probably be more like... invisible clothes. Just let it all hang out!
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What are you talking about? I can clearly see those garments. Why, I'm not sure I've every seen such magnificent rainment, in fact! Such finery, of course, can only be seen by those with the most discerning of eyes, and judgement to match, I daresay.
Surely you can see them as well, can you not?
Re:In laymen's terms... (Score:5, Funny)
Excuse the oversimplification here but....
What I'm getting is, if they take a bunch of particles together in the right combination, then they no longer emit or react to photons? A) huh? B) so invisibility cloak anyone?
I feel a car analogy is in order here.
Lacking a physics background, I'm not the right person to make it.
This being Slashdot, I will anyway. It's like you went to a car sales lot with 100 fully functional cars on display. You put them all into a (really) huge car compactor, and out comes a baseball-sided chunk of metal, plastic, and glass. Its brake-lights don't work.
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I feel a car analogy is in order here.
Lacking a physics background, I'm not the right person to make it.
This being Slashdot, I will anyway. It's like you went to a car sales lot with 100 fully functional cars on display. You put them all into a (really) huge car compactor, and out comes a baseball-sided chunk of metal, plastic, and glass. Its brake-lights don't work.
I feel like a sports analogy is in order here.
Lacking a physics background, I'm not the right person to make it
This being Slashdot, I will anyway. It's like you have a hockey team with a bunch of good players. You then add a bunch of face-punchers who get in fights and act gritty, and out comes a dysfunction train wreck of a hockey team. They don't show up on the scoresheet.
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Actually, you know what? I think it sucks that Tom Magliozzi died the other day. In honor of him, my best impersonation of how he would have fielded this question:
"How the hell would we know?"
Losing Tom sucked. It's still the thing most on my mind.
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Actually, "dark matter" was originally called "dark" because it wasn't hot enough to emit light (the Earth, for example, would be considered "dark matter" under this definition). Dark matter was originally thought to be things like stray planets, cold gas clouds, and the like. People only started looking for exotic dark matter once they realized there wasn't enough ordinary matter to do the job.
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(the Earth, for example, would be considered "dark matter" under this definition)
No, the Earth absorbs and re-emits light in a spectrum related to its temperature. Enough conventional matter would alter the observable properties of galaxies, as indeed free gas and dust does. That's how they know that there isn't enough ordinary matter to do the job: "not dark enough".
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Just too few to see (Score:3)
Magic Matter (Score:3, Insightful)
While I agree that something is odd with gravity, the certainty that many scientists seem to have that it must be an exotic particle or form we have not discovered seems misguided. It could be something exotic and new that doesn't fit with any previously discovered science... or not. Dark matter just fails Occam's Razor in my opinion.
I'm not saying it doesn't exist either... just that I think we need to be more open to alternative theories like this. I'd love to see this particular question answered in my lifetime.
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>Dark matter just fails Occam's Razor in my opinion.
Glad you weren't consulted about quantum mechanics when that was being discovered, too!
Re:Magic Matter (Score:5, Insightful)
While I agree that something is odd with gravity, the certainty that many scientists seem to have that it must be an exotic particle or form we have not discovered seems misguided. It could be something exotic and new that doesn't fit with any previously discovered science... or not. Dark matter just fails Occam's Razor in my opinion.
I'm not sure why this was modded "Insightful" but it suggests that others share your questionable views, so I'll reply to them.
1) Scientists are not certain that dark matter is exotic particles, which is why scientists write papers like the one under discussion here. What seems misguided to me is people who are apparently ignorant of how science--which is the discipline of publicly testing ideas by systematic observation, controlled experiment, and/or Bayesian inference--works commenting negatively on how science works. It's a bit like Creationists critiquing their own bizarre views of "evolution" while ignoring the actual theory of evolution.
There has never been a time in the past several decades when any actual scientist has been even remotely certain about the nature of dark matter. Various ideas have been put forward, including ideas that modify gravity, and none of them have stood up to the routine tests applied to them. This has driven research toward exotic particles.
In particular: Big Bang Nucleosynthesis puts very tight constraints on the density of baryonic matter in the universe, and it's only about 5% of the amount needed to explain the large-scale cosmological observations that imply dark matter. So it isn't like scientists are just saying, "Yay! Evidence of new particles!" Rather we are saying, "Damn, there's a problem we can't solve with baryonic matter."
2) Occam's razor is stupid. You know, of course, that Occam himself used it to "prove" that nothing existed other than God, since to invoke other entities (matter, the Earth, shoes, cats...) to "explain" the phenomenology of experience would be to "multiply entities above necessity".
In the cases when it works or makes sense, Occam's razor is "Bayes' Rule for Dummies". The prior plausibility of a horse being around is higher than the prior plausibility of a zebra being around. Since both horses and zebras create hoofbeats with equal probability, hearing hoofbeats increases the plausibility of the propositions "There is a horse around" and "There is zebra around" by the same factor. Since horses were more plausible before, they are more plausible after.
That is:
p(zebra|hoofbeats) = P(hoofbeats|zebra)*p(zebra)/P(hoofbeats)
p(horse|hoofbeats) = P(hoofbeats|horse)*p(horse)/P(hoofbeats)
Since P(hoofbeats|zebra) ~ P(hoofbeats|horse) and p(zebra) < p(horse) and P(hoofbeats) = P(hoofbeats), it is trivially true that p(zebra|hoofbeats) < p(horse|hoofbeats).
No notions of "simplicity" are required.
So: your comment is quite badly mistaken.
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I think you are being overly hard on the parent. What I read into his words were that by calling it "Dark Matter" we are focusing too much on the possibility that it is actually matter whereas the truth may be far more... different.
For example, someone above proposed that space itself may be "dimpled". Another off-the-cuff proposal is that the convention of "frames of reference" is not defined properly so that the galactic curves may not be what is actually there (assuming there is actually an objective rea
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Besides, I've never understood this objection. We already know abo
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Dark matter just fails Occam's Razor in my opinion.
If you think it's an answer then: yeah, it should.
Dark matter is more like an open question. We don't know what causes the effects we are seeing. "The explanation with the fewest assumptions is probably the best one" doesn't really work when all the explanations require many assumptions.
The best way to research such an open question is
1. Think of more ways this question could be answered.
2. Check the assumptions. Find if they are reasonable.
3. Remove explanations that have assumptions that turn out to be w
not likely (Score:3)
we're talking about clumps of matter with a density of a hundred billion tons per cc that would collide (likely passing straight through with catastrophe on both sides) with the earth at least once a year....that would be VERY noticeable. Even moreso noticeable if the velocity was insufficient to leave the other side, we'd have a growing degenerate matter "star" in the center of our planet, which could only end badly.
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Actually, I think Lena Dunham lives in NYC.
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Ummm ... how would we know that, and why would we expect it? I'm not disputing you, because I have no idea WTF you're saying.
I'm saying you've just thrown out a rejection based on a conclusion I have no idea what it means or what supports it.
Can I play too? Dark matter takes on the form of cosmic, cross-d
Re:not likely (Score:4, Informative)
I actually RTFP. They specifically mention the density, size and frequency of collision with earth of their posited dark matter candidate.
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You know, fair enough on that one ... one does see many "it can't be this because of that" just getting tossed out there on Slashdot.
And most of us haven't got nearly enough background to assess any of that stuff.
Physics at this level gets pretty much into voodoo and "trust us, it's complicated, but we've done the math". :-P
But you can't disprove my cosmic, cross dressing clown theory, so I'm holding out hope. ;-)
Lovecraftian Dark Matter (Score:4, Insightful)
um no (Score:2, Interesting)
Color me skeptical but from what I'm reading...
a form of matter that could only be formed in the early universe
It makes up 5x as much mass as ordinary mass in the universe
It's transparent to light
It's either transparent to heat or just so happens to give off almost exactly the same amount of heat as it absorbs
It has a density somewhere around the same density of a neutron star
It's not managed to devour/destroy any stars or otherwise clump together
It's a fluid
and there just so happens to be none of it on ear
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I think the standard objection to that idea is that there'd have to be so many/much of them/it that we'd have seen them by now.
Re:um no (Score:5, Informative)
There was always an assumption that rogue or orphaned planets could contribute. Cross referencing against observations and known theories yielded a contribution that exists, but is far too small. These are what they are refering to as MACHOs.
There needs to be *a lot* of whatever is causing the discrepancies, and that much "normal" matter would probably be easily measured as the effect that the mysterious matter has is significant enough to require an equivalent mass to something like 20-30% of the mass of the universe. It would be difficult to believe we could be off on our observations by that much.
Cold Dark Matter: http://en.wikipedia.org/wiki/C... [wikipedia.org]
MACHOs or Massive Compact Halo Objects are large, condensed objects such as black holes, neutron stars, white dwarfs, very faint stars, or non-luminous objects like planets. The search for these consists of using gravitational lensing to see the effect of these objects on background galaxies. Most experts believe that the constraints from those searches rule out MACHOs as a viable dark matter candidate.[5][6][7][8][9][10]
Also:
http://en.wikipedia.org/wiki/D... [wikipedia.org]
Studies of big bang nucleosynthesis and gravitational lensing have convinced most scientists[10][80][81][82][83][84] that MACHOs of any type cannot be more than a small fraction of the total dark matter.[8][80] Black holes of nearly any mass are ruled out as a primary dark matter constituent by a variety of searches and constraints.[80][82] According to A. Peter: "...the only really plausible dark-matter candidates are new particles."[81]
Re:um no (Score:5, Interesting)
To follow up, I'd like to point out plot 2 in the article under discussion (go on, have a look. Opening a PDF isn't that painful). It is a plot of part of the parameter space for dark matter particle candiates, with weakly interacting, relatively light particles in the lower left corner and strongly interacting very heavy particles in the top right corner. MACHOs live to the right in this plot, and WIMPs near and below the bottom. The interesting thing about the plot is that it shows all the regions that have been excluded, color coded by how they were excluded. MACHO territory is basically completely excluded by microlensing. That doesn't mean that MACHOs don't exist - they definitely do (the earth basically qualifies, since it's compact and doesn't shine), but there can't be anywhere enough of them for their gravity to be important.
If you make the MACHOs smaller so that they aren't as good at lensing, you have to compensate by having more of them to get enough gravity, so microlensing can exclude a pretty wide parameter range. But if things get too light the lensing effect gets too small for us to detect, ending the microlensing exlusion range at a particle mass of about 10^24 g, about 1/10000 of the Earth's mass. But if they get a bit smaller, then can then be detected using lensing interferometry (=nanolensing), and for even lighter objects, by their imprints on crystals found in deep mines that act as natural particle detectors.
Anyway, I encourage everybody to read the paper: It details all the different techniques used to exclude models. The paper is really quite the opposite of what the [rant]typical Slashdotter anti-science prejudice[/rant] is. It's not somebody pulling some hypothesis out of thin air and then not bothering to test it. As the plot shows, this is really a case of eliminating slice after slice of the model space, with 75% of the area in the figure already being excluded.
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Before the CMB was emitted, the entire universe was an extremely smoothly-distributed ionized plasma. There were no galaxies or stars or planets: just a smooth plasma whose temperature varied from place to place by about one part in 100,000. We can see an image of the universe when this plasma cooled to the point it became a gas. This image shows a very clear signature of dark matter (in fact, it's the most sensitive detection of dark matter density that exists).
This proposal has the same sort of problem
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We would have seen them via gravitational microlensing. This [vixra.org] provides a graph of the limits on dark matter, and the planetary mass range is excluded.
Also, planets (unlike condensed dark matter) would not evade the Big Bang Nucleosynthesis limits on baryonic matter, which rule this out for any mass range.
Re:um no (Score:5, Interesting)
I was very suspicious when I saw the vixra.org link, but you've actually found a non-crackpot vixra article (if a very short one)! I guess it goes to show that one shouldn't be too quick to judge something by its company.
(Some context for other readers. arxiv.org is where all scientific papers in the fields of astronomy, particle physics and related fields are posted and read by working scientists. In these fields it has in practice supplanted traditional journals - on still submits articles to them, but nobody actually reads them, since articles appear on arxiv much earlier, and arxiv is free to everybody and much more convenient than dozens of scattered journals. But not everybody can post on arxiv. One must either be part of an academic institution or be endorsed by somebody who is. vixra was formed as a completely open alternative where anybody could post. But it quickly drowned in a deluge of crackpots. I've sampled it at several points (mostly the astronomy section), and did not succeed in finding a single remotely worthwhile paper in several pages of listing in any of the attempts. Hence my surprise this time.)
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Sure it's a tough list but it's no worse than what people keep trying to come up with
http://phys.org/news157292373.... [phys.org]
Here we have physicists creating a new class of particle with an in principle undetectable fifth long range force as well
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And it clumps together forming the scaffolding for the galaxies, but it also somehow separates out to only show up as a halo around the outer edge of the galaxies. I was just watching this video yesterday to understand what they think this stuff is and many of the things she says contradict themselves. https://www.youtube.com/watch?... [youtube.com]
Plus, nowhere do they ever say they account for time dilation in the galactic rotation speed. If gravity is more intense in the center of the galaxies, then time there will b
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How likely do you think it is that scientists haven't thought of clumping of dark matter or gravitational time dilation in galaxies? It sounds like you really believe that all dem stoopid scientists and their entire field of research have missed your "novel" and "revolutionary" points. I think usually when it seems that way, the natural thing to do is to assume that you've misunderstood something, at least until you've properly researched the issue.
And it clumps together forming the scaffolding for the galaxies, but it also somehow separates out to only show up as a halo around the outer edge of the galaxies.
Have you thought about why our galaxy is the size it is? Gr
Correction: 0.02 light years (Score:2)
The stellar mass of the milky way is about 64 billion solar masses, giving a Schwartzchild radius of 0.02 light years. The time dilations should therefore be corrected to 1% at 1 light year, 2e-5 at 1% of the galaxy's radius and 3e-7 at our radius. It does not change the conclusion noticeably..
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Ok, I went back and looked at what she was saying about the Coma galaxy cluster again. The dark matter was in the center, but the galaxies did not collide like I thought she was saying. They are just swirling around each other.
This isn't just a handwavy argument - when you put dark matter and baryons into detailed physical simulations
You do realize they decide what dark matter must do, then put it into the simulation that way. Of course it will act in the exact way they said it should. That is quite obvious. The question is whether there is actually matter or something else causing these observations.
It seems like
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Ok, I went back and looked at what she was saying about the Coma galaxy cluster again. The dark matter was in the center, but the galaxies did not collide like I thought she was saying. They are just swirling around each other.
Oh, it was about the Coma cluster, not the Bullet Cluster. I apologize for confusing you with an unrelated discussion. The Coma cluster evidence is based on the velocity dispersion of the galaxies in the cluster, not separation of components like the Bullet Cluster is. The argument here is that the galaxies move too quickly compared to the gravity produced by the stars, so if there isn't some extra matter the cluster would blow apart (the Coma cluster is not unique in that way, the same thing is observed in
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Thanks for all of the info. I read up on this stuff, but it is nice to have someone who understands it better put things into another way to look at it that makes things a little easier to understand.
Your point about gravity being a conservative force where the object speeds up the same amount that it slows down when leaving makes sense. I should have thought of that as I do know that objects in space aren't just captured in orbit without making some sort of changes to their velocity. This then makes me won
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The exact GR you speak of sounds interesting. Is that related to calculating the gravity in the galaxy more accurately than treating it as all the mass being in the center?
No, it's a bit more subtle than that. The problem is that General Relativity is non-linear. In Newtonian gravity, which is linear, you can just add up the gravitational influence from each source to get the total force. This is not strictly true in GR. But we know that GR reduces to Newtonian gravity in the weak field limit, and the gravitational field is weak (in the technical sense) in the overwhelming majority of the galaxy (everywhere except very close to black holes), so it makes sense that those few s
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That's not exactly a ringing endorsement. It's more like "Ok, since we haven't found dark matter yet... this is way out there but hey, why not?"
The interesting bit of the paper is pointing out that observational limits excluding Standard Model-ish dark matter are incomplete. This is significant, as the new physics required to make stable "macros" of the kind discussed (nuclear-dense objects in the range of a few hundred grams to around the mass of the Earth, with a gap in the middle) is quite a bit less substantial than that required for physics beyond the Standard Model.
It it not-inconceivable that the strong force could have some weird metastable
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"It's transparent to light"
Came here to say this. It's dark matter because it doesn't seem to emit or block light. Baseball-sized clumps of whatever would block light. We'd know it was there because we couldn't see the stars behind it.
I didn't read the article. Maybe they explained that bit.
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That's not what dark matter is.
If dark matter existed in normal form, the gravity associated with it would be vastly distorting the universe as we know it.
Pretty much, we know that dark matter can't be normal - as you would consider it - matter. All other theories as to what it might be are just as unproven and have just as many holes.
"Baseball-sized" (Score:3)
Glad they didn't say "football-sized" or we'd have to go down that whole units thread yet again.
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Ape #1: Dear me. What are these things coming out of her nose?
Dark Helmet: Hey, hey, hey. Watch my Helmet.
Ape #2: Spaceballs.
Ape #1: Oh, shit. There goes the planet.
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Douglas Adams was right all along.
1 weird theory! (Score:2)
Now you can understand dark matter with this 1 weird theory!
Strange dark matter? (Score:2)
Sounds scatological...
"Old" you say? Eeeww....
Galactic Oort-type cloud (Score:2)
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No. The dark matter is in a Halo (not quite spherical), which extends out from (roughly) maybe 2000 light years to 100,000.
It has to be more or less uniform to give the disk it's more or less flat rotation curve. If it was all on the edge, the mass inside wouldn't really feel it, and that wouldn't work.
LOL ... w00t? (Score:1)
Old, strange, and dark ... I think my wife would say that describes me fairly accurately. :-P
It isn't a "fun" theory (Score:2)
Hitting a baseball-sized clump of matter in interstellar space at 200,000 km/hour could take the fun out of space travel.
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Space Dandy did it. Be more original.
cross section - mass ratio limits (Score:5, Informative)
The various limits on dark matter actually limit the ratio of the scattering cross section and the mass of whatever is making up the dark matter (this obviously does not apply to MOND type theories, which are different).
So, there are two ways to have a more-or-less non-interacting dark matter - have a small mass, and a very, very small cross section (as in WIMPs), or have a large mass, and a high density (as in quark matter [vixra.org] DM theories). The large mass means that the scattering cross section can be more or less anything, and, specifically, can be what you would expect for regular matter.
Real Reason Dark Matter Can't Be Seen... (Score:1)
Real Reason Dark Matter Can't Be Seen: The reason scientist can't find Dark Matter is that they're not looking in the right place. As soon as they look at it then it is not dark matter but normal matter. This is because the Universe is very much like a game simulation in the computer where it only displays what you are looking at, not the things you're not looking at. This selective display saves computational resources allowing a higher, more realistic frame rate. Although the objects aren't displayed they
statistics? (Score:1)