A Theory of Dark Matter
September 8, 2009
Dark matter and normal matter have been wrenched apart by the tremendous collision of two large clusters of galaxies. The galaxies are observed in the optical (shown in orange and white). Most of the normal mass in the clusters (pink) is associated with gas heated in their collision. Dark matter is not visible, but is inferred (blue) from gravitational lensing effects; the dark matter lagged behind the other matter in the collision. The discovery in 2008, using NASA's Chandra X-ray Observatory and other telescopes, provides additional evidence for the existence of dark matter. Credit: NASA and the Chandra X-ray Observatory
Among the most astounding, unexpected, and important achievements of the past century (or even more) have been the discoveries of dark matter and dark energy, collectively dubbed the "dark sector."
A whopping 96% of the essence of our universe lies in the dark sector, where essence refers to everything that controls evolution and large-scale properties of the cosmos. Dark matter is unseen matter -- unseen in the sense that it emits no detected electromagnetic radiation (light, radio waves, etc) -- but it has been definitively spotted nonetheless because its gravity has measurable effects on stars, things that we can see. Of all of the matter in the universe, an incredible 90% is dark matter, with galaxies and stars being only minor constituents. We do not know what dark matter is, only that it is almost surely made of kinds of elementary particles unlike those that comprise normal atoms.
Dark energy, on the other hand, is not a form of matter at all (nor is it literally "dark" -- that is just a poetic way of saying that it is mysterious). It is the source of the outward acceleration of the cosmos, and, based on reasonable assumptions about our current understanding of elementary particle physics, may arise from the vacuum, which has quantum properties that provide energy to the cosmos. Alternatively, dark energy may be a feature of gravity that produces cosmic repulsion on a large scale.
CfA scientist Douglas Finkbeiner, together with three of his colleagues, has published a new paper in Physical Review D with a possible explanation for dark matter.
They are able to approximately describe this astonishing dark matter by making an equally astonishing proposition: the existence of a new force of nature. There are only four known forces in the world: the familiar gravitational and electromagnetic forces, and two forces whose domain is at the scale of the atomic nucleus and are less commonly appreciated, the so-called strong and weak forces.
So far as we know, these are the only forces there are, and scientists have generally supposed that these four will ultimately explain the dark sector as well, once some additional details about particle physics are confirmed with the new generation of particle colliders.
In their new paper, the scientists build on data from five different recent astronomy measurements, most of them probing energetic regimes of astronomy, that have discovered puzzling results including a large excess of high-energy electrons and positrons in space. These particles cannot easily be explained by the conventional sources, shocks from supernova. They could come, however, from the self-annihilation of dark matter particles that, like all known forms of other matter, should come in pairs that self-destruct upon contact. Even without knowing the nature of dark matter, it is possible to argue how it ought to behave so as not to contradict other, known principles and observations.
In working out their self-consistent theory of dark matter, the scientists find that a new, fifth force of nature is implied. Although this might seem an extravagant solution, they argue that it is in fact a relatively straightforward solution, fits into a very reasonable (if novel) picture of particle physics, and fortuitously appears to solve a number of independent problems. The new ideas, if confirmed, would revolutionize our understanding of the universe. This paper, which outlines the basic ingredients of the new model, lays out a concrete first step that subsequent research can now either contradict ... or confirm.
Provided by Harvard College Observatory
Jan 31, 2008 |
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Um... When was this proven?
So now to continue to try and explain away the observations that suggest that we may have it wrong, we now will require a fifth force so everything can fit?
The energy/matter density of the Universe was determined recently by five years of examining the WMAP data of the Cosmic Microwave Background Radiation.
So it split off and we never noticed its existence. It could happen again as the Universe cools.
In fact, I think there is another, as yet undetected, 6th force that condensed out of Gravity, oh about 10 years ago, when I was in my mid-30's. It is an attractive force that interacts with the atoms in my midsection, dragging them downward and causing unsightly, but very huggable, love handles.
I shall call it the Cellular Sagnetic force. The force carrying particle is the Carb Boson.
oh and guess what fazer, your theory is as good as alexa's crap. lol
I can think about it.
http://www.hbci.c...ergy.htm
Come on, nobody measured fifth force directly - it's just an abstract interpetation of quite different observation.
Because they're ignorants in the same way, like visitors of this discussion. For individuals is difficult to accept foreign ideas and to admit, someone else can have its own truth. I have no reason to assume, people differs so much by their very nature.
It is a kludge. It is most definitely not "Among the most astounding, unexpected, and important achievements of the past century".
a) Rotation Curves of stars inside of galaxies
b) Virilization of galaxy clusters
c) Weak Gravitational Lensing
d) Large Scale Structure of CMB
etc..
I crank out DM/DE by the ton.
It is not good news for the DM believers.
You will read what I mean
http://cosmicdark...ics.html
K. Tissa Perera
I've always been struck by the fact a light beam is invisible when viewed from the side... yet it is clearly a flowing stream of energy. Isn't this obviously "dark energy"?
Just would like to see a reference showing that this has been factored into the discussion before I start thinking about new forces and new matter.
None of which gives any insight into what "dark matter" actually is.
For all we know it's the demons of gravitation comming for their due rather than some exotic particulate.
Uh, would have been nice for this report to include some clue as to what their paper actually says...
I would lean towards more than a few respondents hold degrees here. I myself hold two, neither of which applies directly to this field of debate however.
Not having a degree directly related to this field of study does not preclude one from having something to contribute to the discussion.
If the theory is sound then it should easily standup to scrutiny from a bunch of uneducated crackpots like us.
Such stance depends on the consciousness of observer. If we would silly dogs, many (if not all) seemingly transparent things wouldn't give some meaning for us.
The question is, if we are willing to consider dark matter as a fifth force, why not to consider Casimir force as the sixth one, for example?
http://adsabs.har...06.3880L
http://www.iop.or...6901.pdf
How did you make this transition from dark matter to the casimir force? Through what observations do you base this ideology of yours.
And how does the casimir force have any effect over large scales when it's barely detected at small scales?
The very same mechanism works in large gradient of gravitational field, too. Because gravitational field gradient is interpreted as a vacuum mass/energy density gradient in AWT, the CMB photons of constant wavelength are losing energy near massive objects. It means, we're systematically bombarded by more CMB photons from outside space, which results into weak attractive force, which complements gravity. But with compare to gravitational force, this weak pull force depends on dielectric properties of object (i.e. ratio of CMB photons absorbed and reflected) and it's proportional to surface area projected by object in similar way, like Casimir force.
http://www.scienc...4549.htm
Such galaxies could be composed of antimatter (which shouldn't be shielded by dark matter, but attracted by it, instead) or maybe "parallel mater", which differs form matter inside of our galaxy - this could be considered as a evidence of "parallel universes". "Parallel matter" would annihilate in contact with matter our galaxy, but not completely. We can expect many similar surprises during future research.
Indeed. I can imagine all sorts of stuff.
Then if possible, follow that up with a quantifiable prediction.
Imagining things is great and all but if the rubber never hits the road the car can't go.
http://www.scienc...4549.htm
btw String theory exists more then forty years without some observation comfortably.
Because true beauty is timeless.
And those "puzzling results" have recently been precisely "easily explained by the conventional sources" AFAIU. For example, the galaxy center asymmetry was modeled in some papers a few weeks back.
@ Archivis:
When was this proven?
The standard model [how time flies, just last year it was "the concordance model"] was IIRC supported by 3 sigma results in the WMAP 2nd data release. So that would have been adequately tested as of 2006 as I understand it.
[Then you can discuss details. There is still not enough data to test inflation at 3 sigma in isolation, I believe. So that's a task for the newly launched Planck probe. And so on and so forth.]
@ Alexa:
Aether? Aether was falsified over a century ago.
AdS/CFT connection is the obvious one, in addition to the pending high energy experiments soon to be underway at the LHC.
Grand Unification, one of the primary tests to be run at the LHC, is also a method by which String Theory will potentially be falsified.
What is your background again? You like to take shots at other people's but never explain yours.
There is a simple, close-to-experience, "revolutionary" change that could solve the dark sector problem:
Replace the 300-year-old silly idea that mass mediates the gravitational force and with the idea that radiation emanating from mass mediates gravity.
Newton hypothesized that the mass of the sun attracts the planets. It is just as reasonable to hypothesize that it is the sun's radiation that attracts the planets.
I can heat a 210 gm test mass to 400 degrees Cecilius and place it under 3 copper containers filled with ice. A thermally isolated force sensor indicates that the the test mass has increased its gravitational mass by 22% or46 gm. For similar experiments with similar results and a gravitational theory based on spreading infrared radiation see
http://vixra.org/abs/0907
You barely address this in your "spurious effects".
Agreed, there are too many possible "contaminants" in this experiment.
You can not see it, but you would miss it if it was not there.
Think about it ...
This is a nice experiment, indeed - but didn't you forget hot air convection?
Like a thought experiment but with no basis in reality.
You're ignorant, who is skipping posts, because fifth force belongs between classical interpretations of dark matter - here are dozens articles about it and everyone, who is interested about DM knows about it.
http://novan.com/5th-forc.htm
http://www.physor...373.html
over his barn door.
His neighbor: "You don't believe in that, do you?"
Bohr: "No, but my friends tell me you don't have to believe in it for it to work."
http://www.aether...ngth.jpg
It's easy to see the waves getting further apart from each other as time increase, while Hawking is claiming, the Lorentz invariance is "difficult to reconcile" with Newton theory. Of course it is, because it leads into dark matter and expanding universe observations.
This case just illustrates, everyone sees, what he wants and Hawking, the physmatic sees waves of constant wavelength in picture, which illustrates exactly the opposite.
I presume, this is the main reason, why people are getting so upset this idea by now - it relativizes the undeniable achievement of human civilization and/or even their own IQ: "How the hell is possible, we/our scientists didn't invent it a long time before?! It must be simply wrong!"
Well, it's unbelievable - I admit. But your own reactions explains, why certain ideas can remain ignored, despite of their triviality (or maybe just because of it).
Hyperbolic electrons have been demonstrated to exhibit a fifth force that opposes gravity. You can test this yourself. Complete details for experimental apparatus are available.
Hydrino existence has been independently confirmed in US and European labs and has been suggested as an alternative to the missing mass problem.
I am not suggesting that one theory or another explains these results but the experimental proof is there.
What he said:) (He expressed my feelings totally. So what major pubs have any of these so-called theories been published? What predictions have been made? What observations supporting those predictions have been made and peer reviewed? It sounds an awful lot like creationists who spout their Christian dogma not even knowing or caring Christianity did not even invent their myths.
It was falsified by null results in these experiments:
Michelson-Morley experiment, 1887
Trouton-Noble experiment, 1903
Though falsified may be an extreme word to use, the "aether" was pretty much laid in its coffin ready for the lid to be attached at this point in time.