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Matter, Anti-Matter, and a New Subatomic Particle?
sciencehabit writes "Physicists may have finally figured out why the universe contains more matter than antimatter. The key lies in a flaw in the relationship between the two and a potentially new subatomic particle. 'Other researchers, however, say the results, published today in Nature, should be interpreted cautiously. It could all be an effect produced by run-of-the-mill particles'."
Does it ever seem as if they are fudging in new particles and forms matter to account for discrepancies in math or observation? Well, it IS tax season...
A flaw in God's perfect creation?!?!
This space available.
I am no theoretical astrophysicist, but me thinks "Dark Matter" is the name of the current fad stop-gap physics widget which is necessary to balance out equations in their current hypotheses and models.
Doctors once thought that wellness and illness within the human body were caused by the balance between the body's four humors: Yellow Bile, Black Bile, Phlegm, and Blood.
Obviously, there is MUCH more to it than that. It is no different with this.
The actual answers to the universe and its mass-energy balances, origins, and "dark matter", etc.. are VERY likely to also NOT be so simple.
Does "Dark Matter" cease to be dark if you shine a light on it?
you actually REMEMBER the particles-of-the-week?
my screen started spraying Nerdion particles at me when I read your comment
Yeah. Where are the particles we can actually use and relate to, like Bogons, Cluons, and Unobtaneons.
Though i guess most physicists don't study jewish and/or indian spirituality.
IIRC dark matter is required to make the observed rotation of galaxies fit our current model. OTOH: When I was a kid in the 60's black holes were mathematical curiosities.
And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.
our grandchildren will probably look back 50 years from now and wonder how we could be so stupid.
If you mod me down, I will become more powerful than you can imagine....
Sigs are too short to say anything truly profound so read the above post instead.
Would that be, um, flour? The universe is held together by flour?
(Thought I should attempt to reflect the Luddite perspective. Everybody else commenting on this post is being far too intelligent and rational.)
I've calculated my velocity with such exquisite precision that I have no idea where I am.
So did Garrett Lisi predict the new particles? Do they fit into the E8 algebra thing that his theory is based on?
> Except in real life, they don't really invent a new particle too often, they just make one up and name it after something dumb like themselves and hope at some point it's proven that it's real, which the majority of the time it's not.
For example? Can you list some of these please?
I attended a lecture on the CP violation in B and anti-B meson decay at Virginia Tech in 1998. The theory and maths pointed to asymmetry in the binding force of the (respectively) anti-down and down quarks involved. The amount of asymmetry was calculated to be a few parts in a billion. It hadn't then been seen, but the exact nature of the experimental set-up had been worked out (that was the nature of the lecture). Now it has been seen. Now that it has, why pull an unknown particle rabbit out of the quantum hat? What happened to a perfectly good hypothesis derived from known factors which predicted exactly this?
Astronomers noticed an anomaly. They dreamed up dark matter to explain it. Actually, they dredged it up -- the concept had been applied to other phenomena and always found not to be involved if it even existed. Then they set about looking for other signs that matched the theory, and in a fit of circular reasoning claimed it supported the hypothesized existence of the dream-stuff. Now that they're getting away with it so well that The Teaching Company even has a 12 hour lecture series on it for sale, it's encouraging others to invent all manner of invisible widgetons to blame it on, because hey, anyone can do science, but how many people get to dream up something imaginary and get taken seriously? Dream-stuff is sexy even if it doesn't exist. It gets you noticed. It gets you published, and if the publication is more a question than an answer, well, it's invisible or massless or some other quality which makes it unseen by everyone except you and your imagination.
I'm not buying until I see how they dismiss the previous workable theory based on entirely known quanta that predates this supposed discovery by 10 years.
"I may be synthetic, but I'm not stupid." -- Bishop 341-B
Without this "flaw" matter and anti-matter would have cancelled out almost perfectly early on in the Big Bang leaving nowhere near enough matter (or anti-matter) to form galaxies or stars. So this "flaw" is what allows us to exist. I would not call it a flaw, but rather a design feature. Without breaking this symmetry the Universe would be a really boring place, in much the same way that a tree is more interesting than a cube even though the cube has far more symmetry.
If (theory != sense)
then create.newParticle();
Else
publish.newTheory();
Why do you think it is that pi often is needed in calculations? Because someone is using the wrong coordinate system. But pi is not a rational number. It is not the ratio of two integers.
Its the same problem with particle physics. Using the same logic, having to find more and more particles to satisfy some mathematical model makes it pretty obvious that you are in the wrong paradism. People will claim that we have proof that this or that particle exists, but what is a particle to begin with? What exactly is an electron or proton? We have no idea YET.
Because we look back at Einstein and wonder how he could be so stupid to think quantum mechanics was wrong..
I agree there is "something" out there that does have mass and therefore also has gravitational fields.
Since we can't currently *see it* I'll also agree that because it is currently not directly observable it is therefore "Dark" and made of "Matter".
My point is; that it to call it "Dark Matter" and to be done with it leaves things rather vague. Science rarely is so succinct and simple.
Black Hole material is also "Dark Matter" as it too cannot be directly observed.
Enough effects and gravity of the Black Holes' "Dark Matter" exists on the non-dark observable matter nearby to their hypothesized locations to convince scientists that Black Holes do exist (in addition to the math working out decently).
Stephen Hawking is THE MAN.
For all we know, the mysterious "Dark Matter" could really be just a very dense repository of all of the discarded fruitcakes from around the universe. We don't know.
Scientists have an idea about what "Dark Matter" might be, and likely SOME of that will be correct, but chances are that a majority of it will be wrong. It will actually turn out to be something more complicated than 'matter we just can't observe' so it is now therefore decreed to be henceforth called "Dark Matter".
I believe that atoms once were the smallest particles known, that changed. So will this. It may turn out to just be star ash, but Maybe not.
It could be thousands of things or types of matter, likely even stuff that is NOT dark.
If we can make a B2 bomber into "Dark Matter" from the POV of a man by using it's stealth features and electromagnetic radiation adsorbing coverings, maybe there's just plain ordinary matter out there that is rather cold and covered with some cosmic stealth paint.
The math says it exists and there is enough circumstantial evidence that "something" is there. I doubt it has some mystical properties that make it invisible. There are other dimensions in the universe that mathematics has proven exist, maybe being close or intersecting in some way with matter in those other dimensions is actually causing the "Dark Matter" effect.
I hope to live long enough to see "Dark Matter" become as archaic a term as the body's 4 humors are now from my original analogy.
Implying modern day theoretical physicists are stupid probably isn't something you should do unless you know what you're talking about
// MD_Update(&m,buf,j);
All this paper shows is that there is a difference between CP violation in the charged B mesons and the neutral B mesons. This is somewhat unexpected and while you cannot rule out something new it is also true that they cannot rule out QCD (strong force) effects.
The problem the strong force is that it is so strong at low energy that our normal technique to calculate what is going on (called perturbation theory) does not work because, rather than small perturbations, the strong interaction causes huge changes. This means that theorists have to make approximations in order to calculate anything and so their results may well just show a flaw in their assumptions rather than a flaw in our understanding of physics.
An excellent example of this was with my grad student experiment which was also measuring CP violation but with kaons. Before our measurement the theorists were saying that there was absolutely no way at all they could have a certain parameter (epsilon'/epsilon) to have a value greater than 1e-3 and it would likely be a lot lower. So, we measured it at around 1.7e-3 and, lo and behold, the theorists adjusted their models and suddenly it was in agreement with theory.
So while this might be an indication of something new I am not yet convinces that it is anything more than an incorrect assumption in a QCD calculation somewhere. Such calculations are fantastically difficult and while in this case there are things that will make it easier, it is not yet convincing evidence.
If there was antimatter floating in the universe we would see it via the annihilation of anti-matter with matter where they meet. In particular, an electron and positron annihilate into two gamma rays of a very specific energy, and we have space telescopes looking in that energy range. We just don't see them. You could postulate antimatter stars/galaxies, but their solar wind would run into other stars in the interstellar medium, and create these gamma rays along a boundary plane between them. We just don't see that. We've also put detectors in space looking for anti-protons (AMS). We do see some, but not very many. For more info, google "baryon asymmetry" which is the modern name of the anomaly, and is quite precisely measured.
-- Bob
1^2=1; (-1)^2=1; 1^2=(-1)^2; 1=-1; 1=0.
According to Sturgeon's Law we just need to find the crap particle and got 90% solved.
Justice is the sheep getting arrested while an impartial judge declares the vote void.
Actually Newton gets a free pass, one of the two(?) assumptions he wrote down was "time is constant".
And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.
I think there is just more matter than anti-matter; the positive and negative charge pretty much balance. I think that means that I could be carrying a slight negative charge at the moment, but since I'm not a physicist, I'm not positive. (okay, that was weak...)
I think thats a little harsh although has some grounding in reality. It is true that theoretically, there are many many theories out there which predict unobserved particles and one is invented almost every week. The Higgs for example, supersymmetry (SUSY) is another mainstream one. Simply put we have no idea whats going on except that the Standard Model seems to describe it amazingly well. However its incomplete, has many prob such as the baryon asymmetry one being discussed, then the many theories which try to solve these problems and all (or almost all) bring in new particles. This is the scientific method, we do an experiment, we note we dont full understand it and then we hypothesize a theory to explain it. We then test this theory to see if its correct and this is where most of the new theories fall down.
In particle physics right now, the problem is that we have a model, the Standard Model, which we know is incomplete (doesnt include gravity for a start) but it more or less explains every experimental result we've every produced (neutrino masses are argueably accommodated with some small extension). We lack experimental data to even give us a hint what might be beyond it and this has been the case for a long time. So theory has had nothing to do but invent crazy models and wait for the experimentalists to catch up (which we hope to do this year, it'll be exciting). Hence why you see a lot of crazy models around with zero experimental evidence supporting them.
The other problem is that we are all tired and sick of the Standard Model, we want to know whats beyond it so people really really want to find evidence of new physics beyond it. This means that people are quick to jump on small effects and claim its new physics which is probably where you are coming from. Usually they get shouted down by the rest of the quickly community but it does happen with alarming regularity (see pentaquarks, 160 GeV Higgs last year as two recent examples). Whats worse is that for something like the result in the article, its an indirect evidence in a QCD environment which basically means there are so many effects going on, this could easily be explained by the Standard Model. So basically nobody believes it for now. QCD is what binds mesons (such as the B+,B0) and baryons (such as the proton and neutron) together. Unfortunately, we cant solve it right now, except for high energies so often there are many effects which later turn out just because we make a mistake in our approximations in order to get a solution. Compare with the CDF Run I jet excess which later just turned out because QCD effects werent being taken into account. This is the reason that physicists wont believe anything which says new physics right now unless theres a clear unambiguous peak in a mass spectrum, ie make and detect a new particle in your detector. Now this could be genuine evidence but we've all been here before so I think the community takes the feeling that we'll wait for more supporting evidence and for people to offer up alternative explanations before we say its new physics.
Fact is, in science you are never "done with it". So there's nothing wrong with a general classification like "dark matter", because you can take for granted that in the future it will be dissected into more specific kinds of matter.
Just as we first had "atoms" and then discovered sub-atomic particles.
Because we look back at Einstein and wonder how he could be so stupid to think quantum mechanics was wrong..
I was thinking more on the lines of who we voted into office and our reality TV shows, but to each his own.
"I am the king of the Romans, and am superior to rules of grammar!"
-Sigismund, Holy Roman Emperor (1368-1437)
No, it couldn't. One thing that is definitely known is that the dark matter is not made of regular atoms (baryonic matter). Baryonic matter is known to comprise no more than about four percent of the total density of stuff in the universe, versus about 25 percent for dark matter. If the universe were 25 percent baryonic, all sorts of measurements would come out differently than they do:
(1) The primordial abundance of elements, which is observed to be about 76 percent hydrogen and 24 percent helium and a trace of lithium, would be very different. See here
(2) The signatures of acoustic oscillations in the Cosmic Micrwave Background would be much larger than they are observed to be. See here
(3) Any extra baryons would show up in the hot gas between galaxies in large clusters, which is very accurately measured by X-ray satellites. See here.
(4) Dark matter consisting of small condensed objects like Jupiter-sized planets would show up in gravitational microlensing surveys. They don't.
We don't know what dark matter is, but we sure as hell know what it's not, and it is not ordinary matter that just happens to be dark. There are multiple, independent lines of evidence which support this conclusion.
From a sufficient distance it's easy to mistake ignorance for stupidity, and modern theoretical physicists are incredibly ignorant. The community as a whole has only been working seriously at the problem of understanding the universe for a hundred years or so - how could they possibly be anything else?
I am TheRaven on Soylent News
For example? Can you list some of these please?
Wikipedia has a concise and complete list of hypothetical and theoretical particles:
Hypothetical particles
Photino - superpartner ofthe photon
Gluino - superpartner ofthe gluon
Gravitino - superpartner of the graviton
Neutralino - superpartner of other neutral particles
Charginos - partners of charged bosons
Sterile Neutrinos - needed to explain LSND results
Sleptons and Squarks - supersymmetric partners of fermions
Tachyons - particles which travel faster than light
Higgs Boson - the origin of mass
Graviton - mediates gravity
Preons - substructure for quarks and leptons
Graviscalar and Graviphoton
Axion - Peccei-Quinn theory to solve the strong CP problem
Axino and Saxion - form together with the axion a supermultiplet
Supermultiplet - supersymmetric extensions of Peccei-Quinn theory
Branon
X and Y bosons - predicted by GUT theory
Magnetic photon
Majoron - predicted to understand neutrino masses
These are all theories. Maybe there should be an X-prize for someone who can come up with a desktop experiment that can prove or disprove one or more of these theories.
Vintage computer adverts: http://www.vintageadbrowser.com/computers-and-software-ads
Baryons are hadrons (particles composed by quarks), specifically three quarks, and the proton and neutron are the lightest and most stable of baryons.
The Baryogenesis theory, as proposed by Sakharov, describes a set of three conditions which all had to be met together in order to have a matter-asymetric universe. A baryogenic reaction sets off from a baryon-symmetric state to produce a final state which has a greater content of particles than anti-particles; or, in effect, no anti-particles and a "small" ammount of matter particles (in comparison to the number of annihilation photon "sea" which might be interpreted as the Cosmic Background Radiation). According to Sakharov, a potencially baryogenic reaction has to satisfy all of three conditions:
- It must violate the baryonic number, i.e., the number of baryons in the final state must differ from the initial state. This might seem a trivial requirement, but under the current (very successful) Standard Model of Particle Physics, it is not.
- It must violate CP (charge-parity) symmetry. In other words, the physics of the reaction/decay must be different from its charge-conjugated (and parity-conjugated) counterpart. Specifically, the rate of a baryogenic reaction must differ from the reaction involving the corresponding anti-particles, due to a non-trivial theoretical result known as "CPT theorem".
- It must happen away from equilibrium (thermal and "chemical"). In other words, the reaction rate must be faster than the time it takes for the mixture between initial and final state domain contents to mix and reach equilibrium.
The first two conditions are mostly related to particle physics, and the third is more oriented to cosmology and especially the macroscopic treatment of the universe with (relativistic) thermodynamics. IMHO, the trickiest is to find a decay that satisfies the first condition, since in the Standard Model of Particle Physics this should not happen directly (technically, the baryon number operator does not show up explicitly in the Standard Model Hamiltonian).From what I've gathered, this is the job of looking for a "new" particle whose decay can, not only, satisfy the three Sakharov conditions, but also give the correct predictions. The matter-to-radiation content is fairly precise: it's very small, but not null, about 1 matter particle (think "hydrogen atom") per 10 billion (1010) cosmic background radiation photons. It's one thing to find a particle whose decay satisfies the Sakharov conditions, especially one that violates the baryon number conservation "directly" (i.e., as a "first order" process); it's another thing entirely to justify that that same decay is enough to give that particle-to-photon ratio within an order of magnitude.
My sig is better than your sig.
>> since black holes are made from collapsed stars, they are baryonic.
Although I think the original point that dark matter cannot be attributed to black holes is valid, can baryonic conservation within a black hole really be assumed? If I put 10^40 baryons in a black hole, should I expect to get 10^40 back out via Hawking radiation? What does this say about the information content of a black hole? (I don't know much about these topics, so I'd really like to know.)
Also, to respond to the higgs thing...
If we do just find the Higgs particle from the LHC, and nothing more, then that is pretty much the worst case situation. We know that there are problems with the standard model, but nobody knows for sure what part is wrong, and how it is wrong exactly. Everyone is hoping that the LHC will give results that aren't predicted by the standard model, to give us a better understanding in where and why it is wrong exactly.