# Dark Matter



## moderan (Apr 4, 2013)

Scientists home in on mysterious dark matter


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## Terry D (Apr 4, 2013)

Dark Matter is WIMPy!


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## Travers (Apr 4, 2013)

Exciting stuff. 

First the Higgs Boson now dark matter, the guys at CERN are racing through the big discoveries at an impressive rate!


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## Rustgold (Apr 4, 2013)

> and open up new investigations into the possibility of multiple universes and other areas, said researchers.



2nd paragraph in, and they're already into garbage which has about as much evidence as the fiction of a almighty god (in other words none).


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## Travers (Apr 4, 2013)

Rustgold said:


> 2nd paragraph in, and they're already into garbage which has about as much evidence as the fiction of a almighty god (in other words none).



Well it only mentions investigations into the possibility of....

Besides, the weird stuff predicted by the models that predicted dark matter aren't far off from being as fantastical sounding as the news article suggests.


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## Lewdog (Apr 4, 2013)

How long until they find an invisible worm hole to another universe?


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## moderan (Apr 4, 2013)

How is anybody supposed to know that? So on-topic too.


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## Rustgold (Apr 4, 2013)

Travers said:


> Well it only mentions investigations into the possibility of....


What it is, is so-called scientists putting their type of religious mumbo-jumbo into their research.  It's like a Muslim scientist claiming the Quran & Hadiths to be the basis of all science, or a Christian scientist bleating the God did it in their reasoning.
Inserting quasi-religious mumbo-jumbo simply harms the credibility of anything they say about their research; particularly when the theory of multi/parallel-universes has zero relation to dark-matter.



> Besides, the weird stuff predicted by the models that predicted dark matter aren't far off from being as fantastical sounding as the news article suggests.


So, if my 'model' proves gravity, should this mean my 'model' providing that I'm god be classified as proven?


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## Travers (Apr 4, 2013)

> So, if my 'model' proves gravity, should this mean my 'model' providing that I'm god be classified as proven?



Well no, I didn't say that at all, and neither did the article. What there is, is cause to look into it, just like there was cause to look into dark matter.

I don't see what your issue with that is.


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## IanMGSmith (Apr 4, 2013)

Thank Higgs, the sky is not falling.


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## Terry D (Apr 4, 2013)

The discovery and its implications have nothing to do with religion, and trying draw those parallels will only take this discussion in a direction which will doom it.  It would be best to avoid that.


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## JosephB (Apr 4, 2013)

I'll be darned anyway if I can see how any of that had an iota to do with religion. I must have missed something.


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## Lewdog (Apr 4, 2013)

moderan said:


> How is anybody supposed to know that? So on-topic too.




Why?  Any time an element of space is discovered or type of process is defined, it leads to another that many first thought only a hypothesis and could never really exists.  To me, what does the existence of dark matter really prove?  That the idea that empty spaces aren't really empty?  We deal with that on earth, with invisible gases and micro particle taking up the space around us, so why would it be any different in outer space?  Dark matter follows a lot of the same basic principals of the types of matter we already knew about.  It's made of energy and some type of sub-atomic particle that we just don't know yet.  

To me, the only importance this means to me is, that scientists are continuing to discover more and more about space, and the more they learn, the greater the chance that someday we will be able to travel outside our own universe.  With that said, the easiest and most efficient type of travel to get to another galaxy where there could be another planet like Earth that can sustain human life, would be a worm hole.


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## dale (Apr 4, 2013)

Rustgold said:


> What it is, is so-called scientists putting their type of religious mumbo-jumbo into their research.  It's like a Muslim scientist claiming the Quran & Hadiths to be the basis of all science, or a Christian scientist bleating the God did it in their reasoning.
> Inserting quasi-religious mumbo-jumbo simply harms the credibility of anything they say about their research; particularly when the theory of multi/parallel-universes has zero relation to dark-matter.



holy christ. you fundamentalist atheists are just so set in your ways.


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## Terry D (Apr 4, 2013)

I don't want to speak for moderan, but I think his point is that there's no correlation between dark matter and the concept of wormholes.  Dark matter was predicted to exist by the Standard Model (the Big Bang Theory) and subsequent measurements indicated its presence indirectly.  Wormholes are not predicted to exist--their _possibility_ is allowed by general relativity, but not predicted.  The same math which allows for the possibility of a worm-hole also mandates that if one did exist it would collapse on itself almost instantaneously.  They are a neat gimmick for SF, but not a practical solution to interstellar, or intergalactic, travel.


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## Lewdog (Apr 4, 2013)

Terry D said:


> I don't want to speak for moderan, but I think his point is that there's no correlation between dark matter and the concept of wormholes.  Dark matter was predicted to exist by the Standard Model (the Big Bang Theory) and subsequent measurements indicated its presence indirectly.  Wormholes are not predicted to exist--their _possibility_ is allowed by general relativity, but not predicted.  The same math which allows for the possibility of a worm-hole also mandates that if one did exist it would collapse on itself almost instantaneously.  They are a neat gimmick for SF, but not a practical solution to interstellar, or intergalactic, travel.



There have been several things along the same line of worm holes that were never thought possible before.  For anyone to believe that there is life on other planets, and that Earth itself has been visited by anything extraterrestrial, you have to believe that there is some type of 'short cut' out there.  



> The same math which allows for the possibility of a worm-hole also mandates that if one did exist it would collapse on itself almost instantaneously.



The problem with this is, maybe the math is wrong?  Too many times, people want to write recipes for stuff that aren't known to exist yet, thus writing off their ability to exist altogether.  Even Einstein has been proven wrong before.


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## Travers (Apr 4, 2013)

Lewdog said:


> There have been several things along the same line of worm holes that were never thought possible before.  For anyone to believe that there is life on other planets, and that Earth itself has been visited by anything extraterrestrial, you have to believe that there is some type of 'short cut' out there.
> 
> 
> 
> The problem with this is, maybe the math is wrong?  Too many times, people want to write recipes for stuff that aren't known to exist yet, thus writing off their ability to exist altogether.  Even Einstein has been proven wrong before.



I don't think anyone sensible does suggest that we have been visited and most belief in life on other planets comes from an understanding of how life works and the sheer number of stars. Not wormholes.


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## moderan (Apr 4, 2013)

If we have been "visited", it's been by accident. I don't entirely disbelieve in panspermia but I don't believe in directed evolution. And Terry was exactly right. There is no correlation whatsoever between _wormholes_, which are completely theoretical constructions, and dark matter, which was predicted by the prevailing mathematical model of the universe.
To claim slim possibilities on the grounds that the math could be wrong is just erecting straw stars. The further we go in this direction of discovery, the more we find that the math is right, and that the model works.
Personally, I think that the rate of life per galaxy as predicted by Drake's Equation is probably low-however, I think the incidence of intelligent life is a very low sum of that, and spacefaring life lower still. There's no reason whatsoever to traverse interstellar distances to investigate the doings on this little mudball.


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## ppsage (Apr 4, 2013)

> The problem with this is, maybe the math is wrong?


Maybe not so much wrong as incomplete. These reporters make it sound as if the gravitational effects so far attributed to dark matter show up when you drop a teacup, when the truth is it's not until there's consideration of masses the size of globular clusters. Maybe extremely large galaxies. At these masses, adjustments to relativity aren't inconceivable and quite a few are in the works, although working through and reconciling the calculations, like anything to do with relativity, takes time and imagination. Dark amtter probably exists, but perhaps not as importantly and novelly as these writers want to imply.


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## Travers (Apr 4, 2013)

moderan said:


> If we have been "visited", it's been by accident. I don't entirely disbelieve in panspermia but I don't believe in directed evolution. And Terry was exactly right. There is no correlation whatsoever between _wormholes_, which are completely theoretical constructions, and dark matter, which was predicted by the prevailing mathematical model of the universe.
> To claim slim possibilities on the grounds that the math could be wrong is just erecting straw stars. The further we go in this direction of discovery, the more we find that the math is right, and that the model works.
> Personally, I think that the rate of life per galaxy as predicted by Drake's Equation is probably low-however, I think the incidence of intelligent life is a very low sum of that, and spacefaring life lower still. There's no reason whatsoever to traverse interstellar distances to investigate the doings on this little mudball.



That's just it, by the time you get to that low number you're likely talking intergalactic distances. The chances of bumping into another intelligent life baring planet even if you're searching for it would be astronomical.

So why, after all that effort, would you probe the rectums of drunks?


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## moderan (Apr 4, 2013)

ppsage said:


> Maybe not so much wrong as incomplete. These reporters make it sound as if the gravitational effects so far attributed to dark matter show up when you drop a teacup, when the truth is it's not until there's consideration of masses the size of globular clusters. Maybe extremely large galaxies. At these masses, adjustments to relativity aren't inconceivable and quite a few are in the works, although working through and reconciling the calculations, like anything to do with relativity, takes time and imagination. Dark matter probably exists, but perhaps not as importantly and novelly as these writers want to imply.


Because dark matter makes up so much of the universe? If you follow the projections, it's fairly important. Not sure how you're applying "novelly" here.



Travers said:


> That's just it, by the time you get to that low number you're likely talking intergalactic distances. The chances of bumping into another intelligent life baring planet even if you're searching for it would be astronomical.
> 
> So why, after all that effort, would you probe the rectums of drunks?


Yeah...but that takes the discussion in a completely awkward direction. Might be fodder for another thread. I don't think people understand just how big intergalactic distances are. They're just numbers.


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## Terry D (Apr 4, 2013)

Not only is there probably a very low number of technological species, but the probability that any two of them would exist at a curious, technologically advanced level at the same_ time_ is equally remote.  There is no reason to assume that an advanced species will exist long enough to coincide with another.  Nothing, particularly not civilizations, lasts forever.


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## moderan (Apr 4, 2013)

I suppose you could make a case for two sets of technologically advanced species to develop at the same time in the same system, but the chance for it is so impossibly small. I don't, however, disbelieve in space-based life. I don't think respiration in the classic sense is a necessity for a life system. It's just that the chance for encounters is so "astronomical".
The "universe ship" model seems more and more the most likely, and for that we'd have to have at least interplanetary capability.


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## ppsage (Apr 4, 2013)

> Because dark matter makes up so much of the universe? If you follow the projections, it's fairly important. Not sure how you're applying "novelly" here.


Novelly as in the only extant explaination for certain observations. The idea that dark matter makes up such a large percentage is, I believe, mostly calculated from the rotational velocities of some extremely massive systems (globular clusters, is what I remember) which gravitational effect cannot be accounted for by the amount of luminious matter detected there. However, some physicists are making new systems of relativity equations, where gravity and speed of light vary significantly in the presence of such extremes of mass. (This is my understanding, which is doubtless at least somewhat befuddled.) Some of these systems end up fairly coherent but so far none to the extent of the modified Einsteinian ones, which aren't perfectly coherent either though. I think the unexpected rotational velocities are the major evidence for dark matter and that the other indications that exist have alternate explainations available. But I've been off cosmology for a couple years at least and things do change. Mostly I object to the done deal tone of these sorts of popular articles, which hardly scratch the surface of the variety of informed investigation and theorization.


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## moderan (Apr 4, 2013)

The point of such articles, though, is to bring these matters before the heretofore uninformed. They're not written for the in-group.


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## JosephB (Apr 4, 2013)

As a representative of the uninformed, I'd have to say the article is still pretty much greek to me -- there's some mysterious stuff called dark matter and they may have figured out what it's made of -- or something like that. To have some kind of clue, I'll have to wait for the PBS/Discovery channel version I guess. I need pictures.


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## ppsage (Apr 4, 2013)

> As a representative of the uninformed, I'd have to say the article is still pretty much greek to me


The sort of people who write these articles also sometimes write books, wherein they are considerably more able to present both fundamentals and the overall state of (conflicting) thought among investigators. Probably two dozen or so ought to cover cosmological and particle theory to a relatively current state, if you don't watch PBS. If you do, six dozen. I recommend starting with a biography of Neils Bohr.


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## moderan (Apr 5, 2013)

JosephB said:


> As a representative of the uninformed, I'd have to say the article is still pretty much greek to me -- there's some mysterious stuff called dark matter and they may have figured out what it's made of -- or something like that. To have some kind of clue, I'll have to wait for the PBS/Discovery channel version I guess. I need pictures.


Try this



ppsage said:


> The sort of people who write these articles also sometimes write books, wherein they are considerably more able to present both fundamentals and the overall state of (conflicting) thought among investigators. Probably two dozen or so ought to cover cosmological and particle theory to a relatively current state, if you don't watch PBS. If you do, six dozen. I recommend starting with a biography of Neils Bohr.


With all due respect, it's exactly that sort of dismissiveness that keeps people from investigating scientific principles. A bio of Bohr is a good thing to read, I agree. But this is the internet age and such information is readily available.


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## JosephB (Apr 5, 2013)

Dark Matter                            ..............Not Dark Matter

That cleared things up. Thanks.

PS -- I didn't think ppsage's comment was dismissive at all. I thought he was just trying to be helpful. I realize there's nothing preventing me from looking it up on the internet -- and I would have done that if I'd felt compelled to learn more right away. And I won't likely read a book either. I'm fairly  interested in this kind of stuff, and appreciate that people look into it and what it might reveal -- but it's the kind of thing I like spoon fed to me in an easy-to-digest popular documentary. I've got other fish to fry.


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## moderan (Apr 5, 2013)

Well....Mr. Sage's point (imo), more or less, was that those popular documentaries are prone to a certain degree of simplification, and don't actually aid in understanding. Discovery Channel-group stuff seems aimed at a curious twelve-year-old, and PBS maybe at fourteen. Both present a point of view that says "this is so", and there aren't any absolutes-understanding is always under construction.
But they do offer a certain amount of information, and one can follow up given sufficient impetus. If one doesn't follow up, then one's understanding is likely to remain at brontosaurus level, rather than progressing to brachiosaur and beyond.
I still maintain that Pluto is a planet.


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## JosephB (Apr 5, 2013)

moderan said:


> Well....Mr. Sage's point (imo), more or less, was  that those popular documentaries are prone to a certain degree of  simplification, and don't actually aid in understanding. Discovery  Channel-group stuff seems aimed at a curious twelve-year-old, and PBS  maybe at fourteen. Both present a point of view that says "this is so",  and there aren't any absolutes-understanding is always under  construction.
> But they do offer a certain amount of information, and one can follow up  given sufficient impetus. If one doesn't follow up, then one's  understanding is likely to remain at brontosaurus level, rather than  progressing to brachiosaur and beyond.
> I still maintain that Pluto is a planet.



Oh, that's not too condescending. Thing is, I probably wouldn't understand a deeper level of information -- since I know very little about any of it. So I'm satisfied with brontosaurus-level. As someone who's really into this kind of stuff, maybe that's something you don't really get. I'm no autodidact, but I like learning on my own -- I just have to be sufficiently interested in the first place to look into something further.


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## moderan (Apr 5, 2013)

Not meant to be condescending-it's realistic. That's the reading level that the general public is said to maintain, and at which the run of television (and by extension, other media) is aimed.
The brontosaurus wasn't a real animal...it was a misunderstanding of a brachiosaurus skeleton. And that misconception has entered into the sphere of common knowledge despite its complete inaccuracy.


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## JosephB (Apr 5, 2013)

Sure. Most of what I know about dinosaurs I learned watching the Flinstone's. I know they either barked like dogs or complained a lot when they were asked to preform simple household tasks. And brachiosaurus burger just doesn't have the same ring to it.


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## moderan (Apr 5, 2013)

Someone has made their lemonade too tart.


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## JosephB (Apr 5, 2013)

Someone has made _his_ lemonade too tart.


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## Rustgold (Apr 5, 2013)

Terry D said:


> ... there's no correlation between dark matter and the concept of wormholes.  Dark matter was predicted to exist by the Standard Model (the Big Bang Theory) and subsequent measurements indicated its presence indirectly.  Wormholes are not predicted to exist--their _possibility_ is allowed by general relativity, but not predicted.



Which raises the question of why these people are so set on contaminating their work on dark matter with all loads of other garbage (in this case it was multiple/parallel universes).


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## Rustgold (Apr 5, 2013)

moderan said:


> I suppose you could make a case for two sets of technologically advanced species to develop at the same time in the same system, but the chance for it is so impossibly small. I don't, however, disbelieve in space-based life. I don't think respiration in the classic sense is a necessity for a life system. It's just that the chance for encounters is so "astronomical".



Well simple maths.  How old is life on earth?  How long has our species had any type of broadcasting technology?  When you look at this, it represents roughly 0.000003% of the time life has been on earth.  And we're going to fail long before we have the possibility of getting pass our solar system.  Simple maths tells us the chance for encounters isn't realistic.


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## moderan (Apr 5, 2013)

That point's been made several times.


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## ppsage (Apr 5, 2013)

I am also of course very dubious that Joe is going to undertake a reading regime of theoretical physics; my suggestion is friendly, but still facetious. However, going the biography route does bring to the science, elements of personal and historical interest, and also a crucial sense of the ongoing dynamic. This latter not of a size able to fit in press releases. Which is my point. So I *am* recommending the books, highly. Simplification is not the issue; oversimplification is. And the inescapable journalistic sensationalizing. 

It might be possible to replicate the effect of such a reading course via internet investigation; I can't do it, the information is either book-length anyway but more difficult physically, or, usually, fragmentary and disorganized. This is just for foundational understanding; for topical matters, peer reviewed material and up to the minute publication, the internet is invaluable. My interest in cosmology does not extend this far, sometimes it does in sociology, politics and especially history. Televised material is only useful if one is competing on the cocktail circuit. No knowledge taken from there is sufficiently embedded in the essentials of its field to even be considered accurate. I have personally tested this dozens of times.

Beyond this, my take is that, in the present ongoing dynamic of theoretical physics, the physical evidence on the ground for the super symmetry extension of the standard model (particle theory, quarks and such) and it's cosmological implications in dark matter and energy, is very thin. Theoretical evidence, based on coherence of mathematical description, is quite strong. Much of the current interpretation of physical evidence, including probably these satellite positron traces, is only possible based on theoretical calculation. I'm not making light of this theorizing. To the extent that one might believe in a theoretical edifice of explanation, I probably do. But it's good to remember that this establishment theoretical framework is based on the unprovable assumption of the total invariability of C (speed of light), and that, although now, a mere hundred years later, this is widely accepted, it's not universally so, and, as complexities like these dark elements become necessary for continued coherence, the ideas of the VSL (variable C) dissenters (still completely theoretical, as opposed to mostly) begin to offer intriguing simplifications. I'm not saying that relativity theory will be overthrown or proved wrong, anymore than Newton's physics were, but it will be certainly extended and modified and new reference frames, with new rules, probably established. In our era of an evolved quantum mechanics, nobody takes Bohr's atom seriously anymore, even though it started a revolution in particle physics and still helps beginning chemistry students get a clue; a cosmological model that is 71.2% dark energy is almost certainly the same sort of preliminary baby step.


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## moderan (Apr 5, 2013)

Undoubtedly..that folds in to the initial point of post #32 in this thread.
I don't any longer have the math for higher physics, if indeed I ever did, and your points are well-taken. Given that my initial impetus was to provide a small snack for thought, this seems to have been a productive line despite several attempted comedy routines that lacked in charm, though they certainly had some strangeness.
Not so sure that C will be a constant always (as you note, the variable crowd grows larger), but it's unlikely to assume the kind of variance that we poor apes will be able to take advantage of, especially as theorizing isn't the same as provability and the latter is not the same as utility.
The (seemingly imminent) "discovery" of the nature of dark matter would have some value to the overall construct, though we have a long way to go to understanding the cosmological model entire.
Is it an easy matter to present to the populace, given the 6th grade reading level of the body impolitic? No. It is not in the nature of things to present easy explanation. I have a friend who loathes such as Michio Kaku because they dumb-down in order to popularize...but how else to quell the demonization?


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## Arcopitcairn (Apr 6, 2013)

This may seem borderline retarded, but I always kind of liked to think that the darkness of space was simply light from so far away that it has not reached us yet. Silly, I know, but to me, poetic in a way.


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## Morkonan (Apr 6, 2013)

JosephB said:


> ....
> 
> That cleared things up. Thanks.
> 
> PS -- I didn't think ppsage's comment was dismissive at all. I thought he was just trying to be helpful. I realize there's nothing preventing me from looking it up on the internet -- and I would have done that if I'd felt compelled to learn more right away. And I won't likely read a book either. I'm fairly  interested in this kind of stuff, and appreciate that people look into it and what it might reveal -- but it's the kind of thing I like spoon fed to me in an easy-to-digest popular documentary. I've got other fish to fry.



Basically...

Consider that, for practical reasons, "Matter" has mass. You're familiar with gravity, right? Everything that has "mass" also has "gravity." The Earth, the Sun, even you and the spoon you used to eat dinner are effected by, and more importantly, affect "gravity." So, all matter is "pulling" on and being "pulled" by gravity. (In fact, anything interacting with the fabric of the Universe is effected by gravity, including photons and the paths they can take.) Gravity is "forever." Gravity is the "weakest" of all the fundamental forces we know of. But, unlike other forces, gravity never stops. It just keeps getting weaker and weaker, inversely proportional to the distance between two points, but it goes on forever and its effects occur at the speed of light. So, basically, when you walk to your front door, the Earth is pulling on you and you're pulling on the Earth. But, the star Proxima Centauri is also pulling on you, just a very, very, very, very tiny little bit and you, believe it or not, are pulling on Proxima Centauri... or, well, it will experience your gravity in approximately 4.25 years or so, given that the distance between you and it doesn't change. Will your short walk effect it? Probably not.

When we look up into the sky, we see that lots of stars have sort of gathered together into large rotating groups called galaxies. Our solar system is part of The Milky Way galaxy. It's a spiral galaxy, spinning around 600,000 miles an hour, at the distance we're currently at. That's pretty fast.

Well, several smart people, including a couple of guys named Oort and Zwicky noticed that lots of galaxies were spinning a bit too fast... Too fast for the gravity of the visible matter in those galaxies to keep them held together. In short, all those stars at the farthest reaches of those galaxies shouldn't have been able to sustain their velocity around the galaxy! Instead, they should be orbiting a bit slower than they were. There simply wasn't enough mass, generating gravity, to hold those stars at that velocity. There must be something else going on because the observed rotational velocities of these stars did not agree with theory, which had so much other evidence in favor of it that it couldn't be lightly dismissed. Galaxy Rotation Curve

Now, some people proposed that gravity wasn't as we thought it was. They thought that instead of steadily declining proportional to distance, it might hiccup sharply at some particular distance for some reason so far unknown. (Modified Newtonian Dynamics - (MoND). But, nothing else really agreed with that idea, most observational evidence said "Nope" and the most likely candidate to explain the confusion was that there was just a bunch of mass there that we couldn't see. We could see the stars in a galaxy and could even come up with some vague notions of planets that may have been difficult to see. We could certainly see dust and gas and all that sort of stuff that reflected light and could tell, by gravitational lensing (the effect of mass, due to how gravity warps space, on the path that light takes) where difficult to see large bodies of mass, like black holes, would be. But, for some reason, this "dark matter" was just too darn difficult to spot - We couldn't see it, it must not reflect light so it must be made of... Dark Stuff. Later, people also figured out that whatever this Dark Matter is, it must not interact easily with other things, else we would probably see that sort of interaction. But, even if it doesn't interact in other ways with all that visible matter, it still has mass and, therefore, gravity. Soooo... Some people had come up with the idea of Weakly Interactive Massive Particles (WIMPs) and those became a candidate for Dark Matter.

There are lots of galaxies out there. In fact, most of the "stars" you might see through a strong telescope are going to really be galaxies. There's lots of those. And, in every one, the stars on the outer peripheries are rotating faster than they should, given the visible mass of the galaxy and its ability to effect stars at those outer reaches. BUT, if there was a very hard to detect field of mass bearing particles that surrounded each of these galaxies, then the math and the Theory of Gravity, works out perfectly fine with no discrepancies at all.

We know a very great deal about Gravity. At least, we know a very great deal about it, given the tools we have at hand. Gravity might not be something you can experiment with very easily, but it is certainly something that you can observe interacting in a wide variety of natural situations. We don't need to bend light in a lab because we can see its path being bent by large objects in space. We don't need to test how it interacts at various distances since we can see those interactions taking place as planets revolve around the sun and comets go speeding past. From all that we know and the limited direct experiments with gravity we have done and the massive amount of observations we have conducted, stars at the outer edges of galaxies shouldn't be revolving so quickly, given the mass we can see or infer by how much light that mass emits, reflects or refracts. The only answer that matches up with all our neat maths and theories is that there must be some matter out there, generating gravity, that we can not see - Dark Matter.

TLDR Version: The outer stars of galaxies are rotating too fast for the amount of visible matter we see in those galaxies. Therefore, the most likely candidate producing the gravity needed to account for that higher rotational velocity is matter that we can't "see."

(Note: Originally compiled with a bunch of extra junk about flat, concave and convex Universes and funky triangles... But, removed that bit. Hope some of the above helped.  There's also some Big Bang considerations and the "structure" of the visible Universe being formed by clumps of Dark Matter to think about, as well. ie: Galaxies may not have been able to form without Dark Matter!)


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## Travers (Apr 6, 2013)

Excellent Morkonan, though, given that this is a writing forum, I can't help but point out that you have 'affect' and and 'effect' the wrong way around (well, most of the time anyway). 

But, very good :applouse:


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## Morkonan (Apr 6, 2013)

Travers said:


> Excellent Morkonan, though, given that this is a writing forum, I can't help but point out that you have 'affect' and and 'effect' the wrong way around (well, most of the time anyway).
> 
> But, very good :applouse:



ROFL!

Sorry about that. But, I'll leave it... I just got home after traveling all darn day and am tired as... someone who has been traveling all day. I'll leave it for comedic effect...affect... effec... Bah! Whatever.


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## moderan (Apr 8, 2013)

I vote that we put Morkonan in charge of explaining stuff, and hire him a proofreader. His dissertions are certainly effective, and he doesn't affect the highbrow attitude overmuch.
*ducks*
Many thanks for shedding some light on "dark matter"


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## Morkonan (Apr 8, 2013)

moderan said:


> I vote that we put Morkonan in charge of explaining stuff, and hire him a proofreader.



OH GOD NO! 

Besides, who'd be in charge of explaining stuff to _me_?

(My proofreading skills consist of adding commas. It's not that I put them where they should be, I just add them...)



> His dissertions are certainly effective, and he doesn't affect the highbrow attitude overmuch.
> *ducks*



Did you ever notice that your eyebrows start crawling around your forehead as you age? Either they drift down to cover your upper eyelid, resulting in a perpetual scowl, or they crawl up your forehead, making you look constantly surprised. Do you think if I tape them in place, I'll stop aging? 

(I am guilty, at times, of unintentionally sounding condescending and "preachy" when yammering about certain subjects. It's because of the eyebrow thing, I'm sure of it.)

PS - There's a great deal in my explanation that is a bunch of simplistic hand-waving. An initiated physics-minded poster may take exception to some of it. There's also a great deal about Dark Matter and the formation of the visible Universe as well as its topology that wasn't brought up.


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## JosephB (Apr 8, 2013)

Thanks for the explanation Morkonan. I think I might get it a  little. When I said earlier that I need pictures, I wasn't really joking. I'm much more of visual learner. Depending on the subject matter, not so much from dense blocks of on-screen text -- even if it's well written. I certainly appreciate the effort though. Cheers.


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## Morkonan (Apr 8, 2013)

JosephB said:


> ... When I said earlier that I need pictures, I wasn't really joking. I'm much more of visual learner. ...



Then, your wish is my.. excuse to indulge myself in the poor photoshop practices! 

I drewed you some pics! (Links only, since they may be too large for comfortable embedding.)

A galaxy rotates, its stars rotating around a central axis.

http://i.imgur.com/HQkzdXk.jpg

That central axis is determined by the gravity, which is the result of particles having the quality of "mass."

http://i.imgur.com/iFDaoNE.jpg

The aggregate force of gravity from all that mass in the center of a galaxy draws all the outlying mass towards the center, but the angular momentum (rotational velocity) of all those bits of matter keeps them in "orbit" instead of being yanked down to the center of the galaxy.

It was theorized that if we measured the rotational velocity of outlying stars and such on the outskirts of the galaxy and compared it with those towards the interior, the ones towards the edges would be orbiting slower than those towards the center. This is very much like what happens when you watch two pieces of poo go down a toilet drain... A piece orbiting closer to the drain will orbit faster than one that is farther away from the center of the drain. 

http://i.imgur.com/uYtrlcS.jpg

See? The stars closer to the interior of the galaxy were thought to be orbiting faster than those towards the outside of the galaxy. However, when astronomers went to check their idea with reality, they found that this was not the case. In fact, the stars towards the outer edge of every galaxy were rotating a bit faster than any known mechanic could allow for, very close to the same rate as the others.

http://i.imgur.com/UGH3Feo.jpg

People argued about it, but what eventually developed was that the only known mechanic that could allow such a thing to happen must be regular ol' gravity. But, since we couldn't see any masses that would account for that gravity, they must be INVISIBLE!  Or, at least really hard to see. So, they theorized that they must be "Dark Matter" and it must exist in a sort of cloud, surrounding the galaxy. (The "cloud" is actually larger than the galaxy, btw.)

http://i.imgur.com/exx2WYA.jpg

That would account for the strangely similar orbital velocities, since the extra spread out mass would keep things in orbit, even though their orbital velocity was much higher than expected.

http://i.imgur.com/d3UQaK3.jpg

And, this is what has now been confirmed to be true, at least as far as we know, right now. There is some form of matter that doesn't interact well with light and other things, yet still has mass. Mass enough, in the case of galaxies, to keep everything in nice orbits, even though their orbital velocities would seem far too fast when viewing them with the somewhat naked eye. 

(Note: This is just one clue that demands a solution of Dark Matter. Another has to do with the mass measured in the outer reaches of galaxies being far larger than theorized. Also, the "cloud" of Dark Matter in the pic I posted is actually much larger than the galaxy, itself. But, I couldn't fit it in the pic.. )


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## moderan (Apr 8, 2013)

Morkonan said:


> OH GOD NO!
> 
> Besides, who'd be in charge of explaining stuff to _me_?
> 
> ...


Heh. I can explain where to add the commas. And I'd say that the receding-hairline-eyebrow thing has some holes in it. I've been known to drap out the soapbox and at 52 I'm vaguely reminiscent of Cousin Itt.
And I know about the handwaving but it's ok by me.


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## Morkonan (Apr 8, 2013)

moderan said:


> ... I'm vaguely reminiscent of Cousin Itt...



I'm the proud owner of a Darwin Sweater, myself. Though, admittedly, it is only stylishly neanderthalic. But, alas, the hair on my head is not as prolific. I'm hoping that either my eyebrows migrate to higher altitudes or my back hair makes up the difference... I'm not too keen on the idea of a mullet back-hair mane, though. I'm also tired of men in films almost universally being depicted as having flowing manes of full hair and not a scrap of hair anywhere else... It's offensive! Sure, some women don't like a hairy chest or hair, anywhere. But, from experience, I can attest this is not always the case.

And, I'm sure body hair has something to do with Dark Matter, somehow. At least it's somewhat cloud-like and spins down the drain when I take a shower...


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## moderan (Apr 8, 2013)

I wear a ponytail most of the time. It ends at about the level of my kidneys. Also a badly-trimmed goatee (currently). Otherwise I'm a relatively hairless sort. I'm pretty certain that my hair is its own universe. It usually doesn't obey the laws of this one. Maybe it's _rotoscoped_.


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## Morkonan (Apr 8, 2013)

ROFL! That pic combined with your quote... Masterfully done!


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## Kevin (Apr 8, 2013)

I'm hoping to someday achieve that full body, 70s retro, 'Ron Jeremy' look (cause the ladies love it) although I am lacking certain other...attributes.


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## Lewdog (Apr 8, 2013)

I really don't understand the validity of this discussion, as it will be hundreds of years before Dark Matter is equally as important or has the same rights as regular matter.  At which point it will have forgotten the 40 acres of land and a mule we had promised it.


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## moderan (Apr 8, 2013)

Morkonan said:


> ROFL! That pic combined with your quote... Masterfully done!


When we fire, we aim to please. And thank you.


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## empresstheresa (Apr 10, 2013)

From post 42



> So, all matter is "pulling" on and being "pulled" by gravity.




Newton and scientists following him wondered what's doing the pulling?  A string of something, maybe?  Attractions of "gravity particles", maybe?  Newton and others decided they'd never figure it out and put the problem on the shelf.  Then, along came Einstein. 


Gravity doesn't pull matter down from below.  It pushes matter down from above.

It's about the curvature of space.  If you're moving, you have to go where space it. So the satellites travel in a curve around the Earth.    (  changes in altitude of satellites are due to changes in energy which enable bodies to smash through curvatures of space, but let's not go there )


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## Morkonan (Apr 10, 2013)

empresstheresa said:


> Gravity doesn't pull matter down from below.  It pushes matter down from above.



Actually, it's more like "falling" than anything else. But, the imagery of "pulling" that I used took less explaining than the idea that two objects, like the Earth and my computer, are both falling towards each other...


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