Physicists propose mechanism that explains the origins of both dark matter and 'normal' matter
December 10, 2010 by Lisa Zyga
This 3D map shows the large-scale distribution of dark matter, reconstructed from measurements of weak gravitational lensing with the Hubble Space Telescope. The field of view covers about nine times the size of the full moon. Image credit: NASA/ESA/Richard Massey.
(PhysOrg.com) -- Through precise cosmological measurements, scientists know that about 4.6% of the energy of the Universe is made of baryonic matter (normal atoms), about 23% is made of dark matter, and the remaining 72% or so is dark energy. Scientists also know that almost all the baryonic matter in the observable Universe is matter (with a positive baryon charge) rather than antimatter (with a negative baryon charge). But exactly why this matter and energy came to be this way is still an open question. In a recent study, physicists have proposed a new mechanism that can generate both the baryon asymmetry and the dark matter density of the Universe simultaneously.
The scientists, Hooman Davoudiasl from Brookhaven National Laboratory in Upton, New York; David Morrissey and Sean Tulin from TRIUMF in Vancouver, British Columbia; and Kris Sigurdson from the University of British Columbia, also in Vancouver, have published their new proposal in a recent issue of Physical Review Letters. Theyve dubbed the new mechanism "hylogenesis" from the Greek words "hyle," meaning "primordial matter," and "genesis," meaning "origin."
"There are two problems in theoretical physics we are trying to address at once," Sigurdson said. "The baryon asymmetry (why do we have atoms but not antiatoms in the Universe?) has really been a problem since Paul Dirac proposed antimatter in 1928 and it was discovered in 1932. And what is the dark matter? Hints of dark matter have been around since Fritz Zwicky discovered missing mass in the Coma Cluster in 1933, but its identity is still unknown. This mechanism links the formation of atoms and dark matter and helps resolve the baryon asymmetry mystery, as the total dark plus visible baryon balance of the Universe is restored."
In this matter-formation scenario, a new particle X and its antiparticle X-bar (of equal and opposite charge) are produced in the early Universe. X and X-bar are capable of coupling to quarks (the basic components of baryonic matter, e.g., protons and neutrons) in the visible sector as well as particles in a hidden sector (so-called because the particles in it interact only feebly with the visible sector). In this scenario X and X-bar would have been produced when the Universe heated up after inflation, in the first moments after at the start of the big bang.
Later, X and X-bar would decay, partly into visible baryons (specifically, a neutron made up of one up quark and two down quarks) and partly into hidden baryons. As the scientists explain, X decays to neutrons more often than X-bar decays to antineutrons. By the same amount, X-bar decays to hidden antiparticles more than X decays to hidden particles. In this scenario, the quarks would be the baryonic matter that makes up almost everything we see, and the hidden antibaryons would be what we know as dark matter. Through this yin-yang decay pattern, the positive baryon number of the visible matter is in balance with the negative baryon number of the dark matter.
The energy densities of visible and dark matter are really close to each other (differing by a factor of five), Tulin said. In many scenarios, the processes that generate visible and dark matter are unrelated, occurring during widely separated epochs in the early universe through completely different physics. So, this factor of five seems like either a really big coincidence, or it could be a clue that both kinds of matter had a common origin. I think this is the main reason to take seriously these unified models of visible and dark matter genesis.
The physicists predict that this matter-formation mechanism could provide an entirely new way to look for dark matter, since it would leave a signature that could be experimentally detected. As they explain, once in a while a dark matter antiparticle might collide with and annihilate an ordinary atomic particle, releasing a burst of energy. Although this is very rare, there is a chance that experiments on Earth that look for the spontaneous decay of protons could detect dark matter.
We plan to investigate, in more detail, the prospects for dark matter detection in nucleon decay experiments, as this constitutes a distinct signature of our proposal and can open up a new front in the experimental search for dark matter, Davoudiasl said. Other potential signals of hylogenesis can appear in astrophysical observations and perhaps particle accelerator data, and we intend to consider these possibilities in our future work as well.
More information: Hooman Davoudiasl, et al. Unified Origin for Baryonic Visible Matter and Antibaryonic Dark Matter. Physical Review Letters 105, 211304 (2010). DOI: 10.1103/PhysRevLett.105.211304
Copyright 2010 PhysOrg.com.
All rights reserved. This material may not be published, broadcast, rewritten or redistributed in whole or part without the express written permission of PhysOrg.com.
-
From lemons to lemonade: Reaction uses carbon dioxide to make carbon-based semiconductor,
28 comments
-
Thioridazine kills cancer stem cells in human while avoiding toxic side-effects of conventional cancer treatments,
3 comments
-
SpaceX private rocket blasts off for space station (Update),
41 comments
-
Climate scientists say they have solved riddle of rising sea,
30 comments
-
Scotland passes turbine test to harness tidal power,
40 comments
-
How can squinting be used by both a myopic & hyperopic eye?
1 hour ago
-
The need for practical electronic and mechanical skills for aspiring experimentalists
6 hours ago
-
Refraction and splitting of a photon
8 hours ago
-
Total pressure load on a chain...
9 hours ago
-
Water under pressure and temperature effects
12 hours ago
-
Flow, different liquid, pressure
12 hours ago
- More from Physics Forums - General Physics
More news stories
Landmark calculation clears the way to answering how matter is formed
(Phys.org) -- An international collaboration of scientists, including Thomas Blum, associate professor of physics, is reporting in landmark detail the decay process of a subatomic particle called a kaon ...
May 25, 2012 |
4.8 / 5 (12) |
39
|
Is a classical electrodynamics law incompatible with special relativity?
(Phys.org) -- The laws of classical electromagnetism that were developed in the 19th century are the same laws that scientists use today. They include Maxwell’s four equations along with the Lorentz la ...
Lying in wait for WIMPs: Researchers seek to dramatically increase sensitivity of Large Underground Xenon detector
Although it's invisible, dark matter accounts for at least 80 percent of the matter in the universe. No one knows what it is, but most scientists would bet on weakly interacting massive particles, or WIMPs.
May 23, 2012 |
4 / 5 (5) |
14
|
Hall effect at the speed of light: How can you demonstrate relativistic effects with your mobile phone?
The relativistic Hall effect describing objects rotating at speeds comparable with the speed of light has been reported.
May 21, 2012 |
4.3 / 5 (3) |
8
Cloak of invisibility: Engineers use plasmonics to create an invisible photodetector
A team of engineers at Stanford and the University of Pennsylvania has for the first time used "plasmonic cloaking" to create a device that can see without being seen - an invisible machine that detects light. It is the first ...
May 21, 2012 |
4.8 / 5 (16) |
7
|
Family history of Alzheimer's affects functional connectivity
(HealthDay) -- Cognitively normal individuals with a family history of late-onset Alzheimer's disease (AD) may display lower resting state functional connectivity in the default mode network (DMN) of the brain, ...
SpotterRF debuts Radar Backpack Kit (w/ Video)
(Phys.org) -- SpotterRF has announced a special radar backpack kit designed to enhance situational awareness for soldiers on the ground. The company says its special radar is designed for warfighters as part ...
Transvaginal mesh op restores pelvic organ prolapse at price
(HealthDay) -- Transvaginal mesh (TVM) procedures are effective for anatomical restoration of pelvic organ prolapse (POP), but patients report a worsening of sexual function following surgery, according to ...
Travel to high altitudes tied to Crohn's, colitis flare-ups
(HealthDay) -- People with inflammatory bowel disease, which includes Crohn's disease and colitis, may be at increased risk for flare-ups when they fly or travel to high altitudes for skiing or mountain climbing, ...
Thousands of shellfish found dead in Peru
Thousands of crustaceans were found dead off the coast of Lima following the mystery mass death of dolphins and pelicans, the Peruvian Navy said Friday.
Astronomers seize last chance in lifetime for Venus Transit
Astronomers are gearing for one the rarest events in the Solar System: an alignment of Earth, Venus and the Sun that will not be seen for another 105 years.
Dec 10, 2010
Rank: not rated yet
Dec 10, 2010
Rank: 5 / 5 (1)
I can't view the original paper but if experiments like this already exist, I'd assume the researchers have already studied them to see if the amount of energy expected from the collision of a dark matter antiparticle and a normal particle is there...
Dec 10, 2010
Rank: 1 / 5 (10)
http://google.com...+-autumn
Dec 10, 2010
Rank: 1.3 / 5 (28)
Are scientists just trolls - or what I should think about it? Actually I do believe, they're trying to prolong their research as possible into account of the rest of society.
Dec 10, 2010
Rank: 5 / 5 (13)
Dec 10, 2010
Rank: 2.5 / 5 (11)
Dec 10, 2010
Rank: 2.5 / 5 (29)
Dec 10, 2010
Rank: 5 / 5 (13)
Dec 10, 2010
Rank: 1 / 5 (11)
Dec 10, 2010
Rank: 1.4 / 5 (18)
Actually dark matter is rather the gold mine and astrological tarot of theoretical physics. Probable composition of dark matter by mainstream peer-reviewed theories ordered by their average rest mass: quintessence, mirror matter, axions, inflatons, photons, neutrinos and sterile neutrinos, chameleon particles, dark baryons, antiparticles, fotinos, gravitinos and WIMPs, SIMPs, MACHOs, RAMBOs, particle X, DAEMONs and micro-black holes.
Isn't it nice to be payed as a physicist?
Compare the Higgs-mass predictions: the guesses go from 109E-12 GeV to 760E-21 GeV, plus two unconventional theories with 1900 GeV and 10E+18 GeV. There are so many comparably likely models - most of which contain continuous parameters whose values aren't calculable right now - that the whole interval is covered almost uniformly. This similarity of Higgs and dark matter models isn't accidental.
http://arxiv.org/pdf/0708.3344
Dec 10, 2010
Rank: 1 / 5 (12)
Dec 10, 2010
Rank: 1.6 / 5 (7)
I don't understand what you are saying. Gravity is a quality of baryonic matter, there is no energy called matter.
Dec 10, 2010
Rank: 4.2 / 5 (15)
By this logic are you saying that the invisible, "undetectable" creator ghod has the same validity as the proposed particles?
Dec 10, 2010
Rank: 4.4 / 5 (16)
All matter is energy.
Dec 10, 2010
Rank: 2.8 / 5 (4)
Dark matter is based on the discrepancy between galactic spin and the gravity of mass of the visible matter contained in the area. I am trying to stay on that sole topic, if I am capable, that there is no need to invent matter when we have no understanding of quantum mechanics to rule out this being a property/quality/ability of normal everyday matter, much as dark energy, attributed to universal expansion, doesn't require the invention of matter to justify its properties.
Dec 10, 2010
Rank: 3.9 / 5 (11)
Uh, antimatter interacts with matter...pretty strongly...
Dec 10, 2010
Rank: 1.8 / 5 (5)
Dec 10, 2010
Rank: 3.2 / 5 (9)
I was going to ask the same question in response to that recent article about the abundance of "small" stars being much greater than previously thought, but I thought the question was so obvious as to not be worth asking.
If stars are 3 times more common than previously thought, then right there you have maybe 60% to 80% of the "missing mass" that "Dark Matter" was invented to explain in the first place.
A few more nebulae, a black hole here and there, and viola, no more need for dark matter at all.
Dec 10, 2010
Rank: 3.8 / 5 (5)
"But this dense area of vacuum..."
By definition, the density of a vacuum is zero.And don't give me crap about quantum foam. All virtual particles created by QF are annihilated. Except in the case of Hawking radiation.
Is this like being a little pregnant?
Dec 10, 2010
Rank: 3.7 / 5 (13)
Here's a hint for you: We can observe particles distributed throughout the universe and have evidence to believe they exist. It is therefore much, much easier for me to believe there are particles of dark matter out there than to believe it is a god, whose existence I have never seen any evidence of.
And I would point out, that out of the millions of fake gods humans have erected since time immemorial, why would "the real one" be the god you happened to be born into worshipping? I'm sure the faith of the ancients was stronger than yours in many cases. But you KNOW they were wrong, because it's obviously jesus.
Dec 10, 2010
Rank: 5 / 5 (10)
Dec 10, 2010
Rank: 4.5 / 5 (10)
But the problem isn't in the spin so much as it is in the lensing effects.
Dec 10, 2010
Rank: 1.9 / 5 (9)
The real point was that they just found a significant amount of normal matter by, uh, looking for it. I thought one of the main bits of evidence for dark matter was that these large galaxies and galaxy clusters behaved like they had more matter than we could see. Now that we can see more normal matter, doesn't the whole case for dark matter have to be taken back to formula? What else are we just not seeing yet?
By saying we have to triple the mass of the universe, you are presupposing that everything else in the theory is necessarily correct. But couldn't it instead be true that we need more mass in some localities, but less mass overall (to deal with the countervailing problem of dark energy)?
Dec 10, 2010
Rank: 4.3 / 5 (12)
Well, you believe in a magical sky god, so your ceaseless amazement at rational and systematic understanding is understandable.
As for "failed theories", you are hardly in a position to make that evaluation. At least this theory is open to testing, which can't be said for your faith.
Dec 10, 2010
Rank: 4.2 / 5 (10)
Sure this requires a tiny adjustment for the WIMP people but isn't a blow of dark matter as a whole. The name is a place holder, finding those stars means we *found* some dark matter [ie some unobserved matter], it's evidence in favor of the original observation.
I'm sorry are you trying to replace the observation that "there's a lot of matter we can't see" with the claim "there's a lot of matter we can't see"? Do you not see how silly that is?
Besides that just as good an argument for WIMPs as for insanely large numbers of stars or trillions of unicorns hiding inside the stars. It's an argument in favor of everything which makes it an argument that means nothing.
Dec 10, 2010
Rank: 2.4 / 5 (7)
While I honestly appreciate where you're coming from in your position I have to respectfully disagree. I think that, like any other theory, inferences can be drawn given observations.
I don't want to de-rail the thread, BUT I believe that there are aspects of reality that suggest design. Problems with current theories of origin etc.
As to dark matter, I think the lensing observations are the strongest evidence for it yet. Used to think it was bunk, but am becoming more and more convinced.
Dec 10, 2010
Rank: 1 / 5 (6)
Dec 10, 2010
Rank: 1.7 / 5 (12)
Dolt, that would be true if E:=m, where := means three-bars, for is.
Neutrinos do not. WIMPS do not. Learn how to read, and screw the arseholes who gave me 1 *.
Dec 10, 2010
Rank: 2 / 5 (33)
Dec 10, 2010
Rank: 4.1 / 5 (13)
In fact, this gives me the idea of, from now on, always writing "ghost" whenever referring to "god". IMHO, that's a more precise and transparent expression of the underlying notion... And greater transparency can only benefit discourse.
Dec 10, 2010
Rank: 5 / 5 (8)
Neutrinos could contribute something, but they are not believed to be numerous enough, nor non-relativistic enough, nor is there any serious agreement on any mechanisms to not produce relativistic neutrinos in the early universe (i.e. they would be relativistic). So dark matter has many independent lines of evidence, we just haven't observed it yet due to the weak cross-sections. Hopefully thanks to actual experiments we will rule out most theoretical models in the next 10 years.
Dec 10, 2010
Rank: 2.2 / 5 (10)
Haven't you ever read, "God is a Spirit and they that worship him must worship him in Spirit and in Truth"?
We can also find throughout the Old Testament that God is continually refered to as a "Spirit".
Your attempts to mock God and believers has only revealed your ignorance on this subject.
Dec 10, 2010
Rank: not rated yet
(This is me pointing way up to the top post where I asked two presently unanswered questions.)
I keep seeing articles getting close to this concept, but never quite landing on it. So, if I'm missing something indicating that this idea isn't possible I'd be interested in understanding why.
Dec 10, 2010
Rank: 5 / 5 (6)
At least you're brazenly open about your ghostly understanding of all things material. Thanks for so explicitly ratifying my post.
@SteveL,
Matter-antimatter annihilation leaves no particles behind. The result is energy, more specifically high-energy photons (also known as gamma rays.) The energy of the photons is equal to the mass-energy of the pre-annihilation particles, according to E=mc^2.
Dec 10, 2010
Rank: 5 / 5 (7)
Dec 10, 2010
Rank: 5 / 5 (7)
I stand corrected. I was thinking of simple annihilation, like electron + positron.
However, barring serious charge-parity violation, any secondary particles produced by more complex annihilations (e.g. proton vs. antiproton) will be balanced out by their antiparticles (e.g. neutrinos with antineutrinos, muons with antimuons, etc.) which, if also allowed to annihilate (rather than shooting away in all directions), would eventually (sooner or later, possibly through another cascade of reactions) yield high-energy photons as well.
The point being that photons have the simplest structure/lowest internal entropy of all, and so they're always the final byproduct.
Though there is, currently, a controversy regarding whether neutrinos and antineutrinos can really annihilate, or whether there really is any fundamental difference between the two in the first place (my guess is, they can, and there is...)
Dec 10, 2010
Rank: 3.2 / 5 (9)
LOL, was that meant as a pejorative?
Dec 10, 2010
Rank: 4.1 / 5 (9)
Scientists, unlike priests and true believers can at least show indirect evidence of actual processes occurring in the universe around us. When it comes to a creator God, it seems strange that we are told he exists, he runs the whole universe but cannot show even indirect empirical evidence for his existence. Even something as simple as appearing to everyone and saying "Hi, I'm God." Strange that.
Dec 11, 2010
Rank: not rated yet
Dec 11, 2010
Rank: 1.4 / 5 (11)
Why are you trying to cast your pearls in vain.
My dad use to tell me, In the Bible it says "the fool has said in his heart there is no God", so I don't waste my time arguing with fools.
Bring on the 1*, fools.
Dec 11, 2010
Rank: 4 / 5 (4)
Be a good boy and go study your fairy tales. Clearly you didn't know that you can infer proof for any crazy ass thing you could ever possibly dream up if you look hard enough in the bible.
http://www.youtub...PrJ6et8k
Dec 11, 2010
Rank: 1.5 / 5 (8)
Reference to a youtube video...Wow that is impressive. Talk about fairy tales...
One fool and counting.
Dec 11, 2010
Rank: 4 / 5 (4)
Dec 11, 2010
Rank: not rated yet
Matter-antimatter annihilation leaves no particles behind. The result is energy, more specifically high-energy photons (also known as gamma rays.) The energy of the photons is equal to the mass-energy of the pre-annihilation particles, according to E=mc^2.
Thank you for your response. What I was leading into was a query if non-baryonic matter (normally undetectable in small quantities due to insufficient energy signature) could result from a matter vs. antimatter interaction. But, I suppose if the math is accurate that the energy produced is exactly equal to the combined mass energy before the interaction - the point would be moot.
Dec 11, 2010
Rank: 1 / 5 (7)
A2G, everything you need to know about Gods and Scriptures is here: http://google.com...mn" . There's even a funny counterpassage to your Psalm line.
Skeptic_Heretic: You are this unlearned. http://google.com...+virtval and http://google.com...stdicand
Dec 11, 2010
Rank: 1 / 5 (1)
A five times difference may be close enough to wonder if there is a connection but it is quite a lot if you want to say that dark matter is anti-matter which "balances" out the normal matter. This discrepancy needs a good explanation to make headway.
Dec 11, 2010
Rank: 1 / 5 (1)
A five times difference may be close enough to wonder if there is a connection but it is quite a lot if you want to say that dark matter is anti-matter which "balances" out the normal matter. This discrepancy needs a good explanation to make headway.
Dec 12, 2010
Rank: 5 / 5 (3)
Dec 12, 2010
Rank: 1 / 5 (4)
http://en.wikiped...astrophe
This is all, what the mainstream physics can say about this subject.
Dec 12, 2010
Rank: 2.3 / 5 (3)
Actually, most of the New Testament was written in Greek, and the word translated "Spirit" is almost always from "Pneuma," which of course means "Breath" literally.
In the old testament, it's the Hebrew "Ruwach," which has basicly the same meaning: "Wind" or "Breath".
It would be interesting if for once the atheist could refrain from just blatantly lying about the facts.
Dec 12, 2010
Rank: not rated yet
Dec 12, 2010
Rank: 5 / 5 (2)
Dec 12, 2010
Rank: not rated yet
Dec 12, 2010
Rank: not rated yet
Dec 12, 2010
Rank: 5 / 5 (1)
Read the 14th and 15th chapters of John's gospel.
It is clear that the "Holy Spirit" is a person, a "He", also referred to as the "Comforter" (Paraklete) "one called beside to help".
Context.
So anyway, the attempts to discredit this as some sort of bad translation are shown to be in error due to CONTEXT of the passages, which shows that the "Spirit" is indeed referring to a "person" who is that aspect of the eternal Godhead, which is the Holy Spirit.
The context does not imply "air" or "wind".
Dec 13, 2010
Rank: 4 / 5 (4)
Dec 13, 2010
Rank: 1 / 5 (2)
If you want a evolutionist universe; invent one.
If you want to chat between universes, simple:
"Uhura, open a subspace channel" "Yes captain."
Dec 13, 2010
Rank: 3.7 / 5 (3)
Dec 14, 2010
Rank: not rated yet
Dec 14, 2010
Rank: not rated yet
If one needs 100% matter for our current theories to work (I'm not saying they do or do not) One sees 5% matter and then concludes that the rest is hidden. If that same scientist then discovers that the amount of dim stars is about three times bigger. For how much of the needed matter would that account. You're right about 10 to 15 %. So either this dark matter/energy is out there or our theories are wrong. Both cannot be false.
Dec 14, 2010
Rank: 5 / 5 (2)
We have the matter caluclations based on a very complex calculation that shows the distribution of baryonic matter compared to observed matter, observed rotation speeds of galaxies and solar systems, etc.
Basically these are gravity calculation. So unless someone determines that gravity doesn't follow the inverse square this revelation identifies exactly zero percent of the missing matter and simply points out what a larger percentage of the already counted baryonic matter has arranged itself in.
We've gone from, "I have 3 dollars in change in my pocket" to "I have two singles, and 4 quarters in my pocket." Haven't read it but I'll pick it up.
Dec 14, 2010
Rank: 1.2 / 5 (22)
http://www.arabac...ames.htm
Dec 14, 2010
Rank: 4.3 / 5 (6)
Dec 15, 2010
Rank: 1 / 5 (1)
condensation of energy ( undefined dimentional entities) result in all known and yet to be know matter
dark matter ( is a an almost dimentionless energy i.e a minimal dynamic energy) it tends to suck everything in to restore dimention and restore it's dynamics( black holes)
it's aloop of events
big bang is only a part of the story
the part of the universe we know is expanding bcus the dimentionless enegr sucked the cconstitiuents of other parts of the universe we are into the process of expansion that will come to a halt when ENOGH IS SUCKED IN)
void does not exist WITH IN THE UNIVERSE
like the microtubules of the cell the universe channels energy and enery products every where
minimal number dimentions are 3
maximum is coutless ( dimentions are being created and engulfed on instant basis
thats it
Dec 16, 2010
Rank: not rated yet
Could non-baryonic matter be made up of loose neutrinos, muons, antineutrinos, anti-muons, etc.? Also, how does a sub atomic particle decay to a higher energy state (high energy photon)?
Dec 16, 2010
Rank: 5 / 5 (2)
That's based entirely on what you were taught by a festering virginal dog-collared vampire.
Dec 18, 2010
Rank: 4 / 5 (4)
I hadn't, but I did some research. I don't place much stock in his theory. The book was published in 2008 but hasn't exactly set the physics community alight. Part of the reason is that to get rid of dark matter and make the equations fit observations he proposes a variable speed of light, which has no observational support, unlike dark matter (eg, gravitational lensing).
Dec 18, 2010
Rank: 5 / 5 (1)
Dec 19, 2010
Rank: 3.7 / 5 (3)
That would be a daring generalization as you can't know - let alone analyze - more than 2 billion people personally.
You obviously didn't argue very often and/or with many drunks. Some of them are very understanding when a friend tells them better not to drive.
There's another flaw in your string of characters: How could there be dropouts from religion if they all were psychos unable to be argued with? By what mechanism did they lose their religion then? A miracle?
Dec 20, 2010
Rank: 1 / 5 (2)
It could be,detection of such a gamma bursts,direct prooff that dark matter is antimatter!