STILL KICKING: The DZero experiment at Fermilab's Tevatron collider, one of two detectors where protons and antiprotons collide at nearly the speed of light.
Image: FERMILAB
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The Large Hadron Collider may be up and running outside Geneva, but the particle accelerator it supplanted as top dog in the particle physics community appears to have a few surprises left to deliver. Data from the workhorse Tevatron collider at Fermilab in Illinois show what appears to be a preference for matter over antimatter in the way an unusual kind of particle decays, according to a new analysis in a Tevatron research collaboration.
Physicists and cosmologists seek such mechanisms to help explain why matter prevailed over antimatter in the early universe, when both should have been created in equal parts, yielding a storm of mutual annihilation and not the stable material structures—galaxies and the like—that fill the universe.
Some properties of high-energy physics have been shown to be fundamentally asymmetrical, producing matter more often than antimatter, but in quantities too small to explain the relative dearth of antimatter in the universe. The new mechanism observed at the Tevatron's DZero detector appears to work on a much larger scale, says Fermilab staff scientist Dmitri Denisov, co-spokesperson for the DZero collaboration, but whether it can explain the preponderance of matter today remains to be seen. In any event, the asymmetry does not fit with the long-reigning Standard Model of particle physics, suggesting that some hitherto unknown particle or interaction may be at play.
The DZero collaborators analyzed more than seven years of proton–antiproton collisions in the new study, which the group submitted to Physical Review D and published online May 16. As the exotic, short-lived particles produced in the collisions progressively decayed to more stable particles such as electrons, a collision product known as a neutral B meson appeared to decay more often into muons—unstable particles that exist for roughly two millionths of a second before decaying further—than into antimuons.
"While colliding protons and antiprotons, which creates neutral B mesons, we would expect that when they decay we will see equal amounts of matter and antimatter," Denisov says. "For whatever reason, there are more negative muons, which are matter, than positive muons, which are antimatter." According to DZero member Gustaaf Brooijmans, a physicist at Columbia University, "We observe an asymmetry that is close to 1 percent."
Brooijmans notes that other experiments have used B mesons to expose fundamental asymmetries in physics but that the results of those experiments have adhered more closely to the Standard Model's predictions. So-called B factories have been built to explore the properties of the unusual particles, but in a more limited scope than that available at the Tevatron. "There is one big difference" between the DZero result and those of the B factories, Brooijmans says. "We have access to the Bs meson, and B factories have access mostly to Bd."
Both Bs and Bd mesons (so named because they contain a strange quark or a down quark, respectively) are short-lived, decaying away in roughly 1.5 picoseconds, or 1.5 trillionths of a second. They are known as neutral mesons because they carry no net electric charge. In their brief lifetimes, they can oscillate between two forms, each the antiparticle of the other, Denisov explains. The difference is that Bs mesons oscillate much faster, giving them more flexibility to change from a matter progenitor to an antimatter progenitor, or vice versa. "Neutral B mesons are really interesting because they can basically go back and forth between matter and antimatter, to simplify things a bit, and we would have thought that they would spend an equal time as each," Denisov says. "What we're measuring now, it looks like they prefer matter."
Even within the halls of Fermilab, the new result from the tight-lipped DZero group came as a surprise, says theoretical physicist Bogdan Dobrescu, a staff scientist at the lab. "It's very exciting," Dobrescu says. "This kind of important announcement is not made too often." All the same, he says, the result must check out in other experiments before it can gain much traction. "It needs to be confirmed before we change the textbooks," he says.
Dobrescu says it is too early to speculate on how much of a player the new mechanism might be in establishing matter's prevalence in the universe. "However, all this notion of explaining matter–antimatter asymmetry should not be the central aspect of this discussion," he says. "We are up against something more important, which is, what are the laws of physics? The matter–antimatter asymmetry is just one implication of that."
It is fairly simple to put down on paper a new particle that could explain the asymmetry in B meson decay, Dobrescu says, but it is more difficult to reconcile those hypothetical particles with what is already known. "Most of the time, if you are careful, you will see that your choice is already ruled out by other experiments," he says.
If it turns out that a new particle is in fact responsible for the odd tendency of B mesons to favor matter over antimatter, it might be unmasked in the unprecedented high-energy collisions at the Large Hadron Collider, or LHC. But don't count out the workhorse stateside, which has a head start of many years—and reams of well-understood data—on its more powerful European counterpart. Brooijmans says his "gut feeling" is that such a particle should be observable at the LHC. "And who knows?" he adds. "It might be accessible at the Tevatron."
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29 Comments
Add CommentOr, could it be that the only known distinguishing characteristic of matter and antimatter, electrical charge, is determined by the orientation of the property of spin in relation to a particle's emission?
Reply | Report Abuse | Link to thisCould it be that the initiating universal energy was spinning in one direction rather than another?
Nah, if it were that simple the expert particle physicists would have figured it out long ago...
The way I see it, you only need a little bit of asymmetry to start the whole thing off and whichever prevails will continue to become more dominant.
Reply | Report Abuse | Link to thisBasically, it works like this:
1. Big bang, Matter and antimatter produced in slightly unequal parts.
2. The matter that pairs up with antimatter is annihilated, but the asymmetry leaves some matter behind.
3. The annihilation is like a reset and mini-big-bang such that it produces matter and antimatter again, with similar asymmetry.
4. Lather, rinse, repeat as needed, the results are cumulative. Matter becomes increasingly common, antimatter increasingly uncommon.
Some work that is not at all well known, suggests that the matter-Antimatter problem has some logical inconsistencies.l If the anti-electron be "anti-matter" then also is the proton for if a person analyzes the comparative rwest mass values and realizes that "mass" is a variable, it can be seen that the proton may sensibly by considered to be "an anti-electron" which has had, somehow, abou5 41/42 of a kinetic energy converted to "mass."
Reply | Report Abuse | Link to thisSame holds for electron and anti-proton. If electron be "matter" then also the "anti-proton " is as both have the same rotational-inversiional characteristics as vortices.
My " research" suggests that atoms are made up of a balance of "matter" and "anti-matter," with the rotation-inversion characteristics of our Univers (which may be an "oversized analog of an electron.") may be the reaason that we find our external measusrements of atoms sexpressed as "matter" with the nuclei of atoms containing primarily the "anti-matter expression (in what we call the "nekutron count."
I am scheduled to give a paper, by remote at the Vigier 2010 Symposium, on my work, the working title is , "The Organic Substance Model as a Framework for a Uniftying Theory... Much of the information to bve comvered is listed in "pages" on the Google Group, http://groups.google.com/group/oscillatorsubstance-theory.
Thank you, Dean L(eRoy)Sinclair, (BA, MS, PhD) deanlsinclair@Yahoo.com
Sorry, people. about the various typos above, Particularly misleading is the "Organic" Substance Model. Wht the title is, is Oscillator/Substance Model. It is a model which considers all existence to be within a Pervasive Something the motions in which are made up of/ controlled by oscillators.
Reply | Report Abuse | Link to thisEssentially, this is an up date of the ancient Aether Theory with inclusion of the Law of Force and some other insights from basic mathematics and electronics. Biggest major shift is probably considering that constants of nature are probably not absolute limits but rather asre statisstical averaage values. For instance, "c, " would be an average velocity of motion in any direction, or an average tangentiaL veoicty of basic rotors, "h" an average angular momentum. and the ratio, "h/c," an "average torque constant " of what ever the basic units of "our Perceptual Universe" wherein "h" and "c" apply. Thanks. I tried to be more careful on the spelling this time. DLS
deanlsinclair - Aren't you cross-associating the characteristic properties of fundamental particles? I don't know, but aren't antiparticles considered to have identical mass but polar opposite electrical charge of it antithetical particle?
Reply | Report Abuse | Link to thisNot to dismiss your concept, but doesn't this idea conflict with all established particle theories? Won't it extraordinary proof be required to interest particle physicists?
I suspect that the 3 generations of fermions' differential masses are merely an experimental artifact, attributing higher rest mass to particles 'produced' at higher test velocities (and higher effective mass).
Perhaps the characteristic properties of fundamental particles are interrelated. It seems intuitive that charge could be functionally related to spin, although there seems to be no statistical relationship.
I suspect there is more to be discovered in the relationship of mass and particle motion, which is not even considered in particle theories.
But the simplest likely universal asymmetry seems to me to be directional rotation, or spin. I prefer the simplest effective solution, especially when the possibilities conflict with established ideas.
jtddwyer...Your very last comment is right on.; Diredrional rotatiion,, "spin" coupled with inversion does seem to indeed be the situatiion Yes, most current particle theories, simply postulate extra particles and none of them consider the probability that the unknown factor of charge, is actually a product of a particular rotation/inversion orientation. to be blunt, yes, most current particle theories are based on erroneous misapprenhensiions. One is the fact that "mass: remains undefined in most of them, as does "charge" and even the very loosely used term, "Energy>" which usually menas "kinetic Energy" motion along a line with relation to a point and should be differeentiaated from vibrational-rotational energy of "point-centric" entitities, the characteristic which we actually measure as the tension/pressure on the surface of the entity as "mass."
Reply | Report Abuse | Link to thisMore and more evidence is accumulating that the "standard Model of Particle Physics has a very shaky base and has the same kind of pertinence that the Geocentric Model did to the Heliocentric.
jtddwyer...Your very last comment is right on.; Diredrional rotatiion,, "spin" coupled with inversion does seem to indeed be the situatiion Yes, most current particle theories, simply postulate extra particles and none of them consider the probability that the unknown factor of charge, is actually a product of a particular rotation/inversion orientation. to be blunt, yes, most current particle theories are based on erroneous misapprenhensiions. One is the fact that "mass: remains undefined in most of them, as does "charge" and even the very loosely used term, "Energy>" which usually menas "kinetic Energy" motion along a line with relation to a point and should be differeentiaated from vibrational-rotational energy of "point-centric" entitities, the characteristic which we actually measure as the tension/pressure on the surface of the entity as "mass."
Reply | Report Abuse | Link to thisMore and more evidence is accumulating that the "standard Model of Particle Physics has a very shaky base and has the same kind of pertinence that the Geocentric Model did to the Heliocentric.
"More and more evidence is accumulating that the standard Model of Particle Physics has a very shaky base and has the same kind of pertinence that the Geocentric Model did to the Heliocentric."
Reply | Report Abuse | Link to thisReally? I suspect that your thought processes are as "shaky" as your typing. Please don't believe that because you can string some terms together in ways not previously done that you are an original thinker, and everyone else is wrong.
The same applies to you, jtdwyer.
biggus56 - Oh, what, you don't like my typing, either?
Reply | Report Abuse | Link to thisDo you have some specific issues, or do you object to anyone thinking outside the little box? In my experience, when the subject area experts have a problem they cannot solve, they're doing something wrong...
The antimatter can have other physical sense. Coal is not antidiamond. If particles have opposite properties, it can not mean the antimatter fact. We can not see an antimatter.
Reply | Report Abuse | Link to thisWhat happens when a anti matter black hole or star and a matter black hole or star collide or get close to each other?Do anti matter stars shine?Or do they have anti photons that are traveling backwards in time?
Reply | Report Abuse | Link to thisjack.123 - As I understand, no antimatter has been detected, only antiparticles. It is presumed that if sufficient antiparticles were available in the absence of antiparticles antimatter would be formed.
Reply | Report Abuse | Link to thisAs I understand, antiparticles are identical to their opposing particles except for their polar opposite charge characteristic property. Their is no antimass or antigravity.
As I understand, black holes are a characteristic of space-time contraction produced by a high velocity collapse of massive objects. They do not actually contain matter: all 'ingested' matter is decomposed by extreme velocity; the gravitational effect of its mass is locally retained, directed to a local singularity, but its material energy is ejected as disassembled fundamental particles with little or no mass. The 'singularity exists because there's nothing in it, but spacetime remains contracted around it.
As such, if a black hole produced by antimatter merged with a black hole produced by matter, they would simply be two identical black holes merging.
Stars, of course, do contain matter. Keeping in mind that no antiatoms of antimatter have ever been detected, if they existed and formed a antistar, then came upon a regular star, as gravitation would cause them to approach they would likely annihilate each other, producing a lot of photons.
As I understand, nothing 'travels backward in time', including antiphotons. Since photons have a neutral electrical charge, they are would be identical in matter and antimatter, although there is some idea that photons and antiphotons could annihilate each other, but I don't follow. I suggest you refer to:
http://en.wikipedia.org/wiki/Antimatter
Pardon the antitypo: the second sentence above should read:
Reply | Report Abuse | Link to this"It is presumed that if sufficient antiparticles were available in the absence of particles antimatter would be formed."
Is it possible that the particals loose there pollierties because of the rapid change of forms , when something is born or created something else dies,VIE the Energy,when a Black hole is presant, it is stronge enough to puul away energies frm bot particals which causes darkmatter.it is waht hols everything together for a monent and when the energies are released, it dissapperas. James.
Reply | Report Abuse | Link to thisI may have overlook a critical factor involved with the production of black holes: rotational orientation in respect to polarization. Black holes produced by matter and antimatter, respectively, would both represent gravitationally contracted spacetime containing no matter, but they might be rotating in polar opposite directions.
Reply | Report Abuse | Link to thisThe result of their merger might possibly be the dissipation of their gravitational energy (contracted spacetime) in the production of photons and perhaps other, massive, particles (and/or antiparticles?).
That's would be a very interesting hypothetical event, possible only if enormous amounts of antimatter also existed someplace: evidently it does not.
Could such an event occur early in the universe where anti stars and black holes colliding with matter stars and black holes producing gamma ray burst?
Reply | Report Abuse | Link to thisjack.123 - If you ask me, there were few if any antiparticles because the rotating initial energy produced only similarly spinning particles.
Reply | Report Abuse | Link to thisIn the earlier, denser universe, it would seem particularly unlikely that separate regions of particles and antiparticles could contain sufficient mass to produce stars and black holes that could then come into proximity with each other. I suggest you refer to:
http://en.wikipedia.org/wiki/Antimatter
then proceed to:
http://en.wikipedia.org/wiki/Antiparticle
David Cota - Quantum theory allows for tunneling at quantum scales.
Reply | Report Abuse | Link to thisLikewise, I don't find where Perturbation theory of quantum mechanics is related to cosmology. From the little I understand, Feynman diagrams do represent a particle propagating either backward or forward in time. However, it's a large leap to extend the quantum propagation of particles to the big bang.
It's not the Feynman-Stueckelberg Interpretation that claims that it is physically real, but Trevor Pitts who argues in the paper you referenced, "Dark Matter, Antimatter, and Time-Symmetry" that this interpretation is physically real. I'm sorry I can't evaluate this paper further, but I do have a few conceptual issues:
--- If antimatter had been created in the early universe, moving backwards in time, it would soon have preceded the big bang event.
--- It would seem that any photons produced would have also be moving backward in time, and could never be detected by an observer in the parallel positive-time universe.
I won't go on. You and Tevor may be correct, but I don't understand how that could be. I'm obviously not an authority to be convinced - I'm simply a reader expressing my own thoughts and opinions.
David Cota - I'd speculate that electron tunneling is occurring only at quantum scales in the graphene, repeatedly through the macro scaled perfect crystal lattices.
Reply | Report Abuse | Link to thisYou're correct - I was never really interested in physics per se, and was completely consumed by professional and other demands since the early 1990s. I did resume some general reading and began investigations of a few specific issues about two years ago.
Perhaps somewhat like the young Sidhartha, a couple of very simple realities were revealed that conflicted with well established beliefs. Unfortunately, I found it impossible to discuss these issues with scientists, since I had no credentials and could not communicate in the context of current research using proper terminology. Being persistent, I am simply doing what I must to communicate some simple revelations, please refer to the essay “Mass Distribution Characteristics Invalidate the Galaxy Rotation Problem”, posted at:
http://www.sciencewithoutfiction.com/uploads/Mass_Distribution-_Galaxy_Rotation_Problem.pdf
If we always acknowledge the possibility of our ignorance, we may better recognize the presentation of reality. Thanks for the interesting information and kind remarks.
I have some issues.
Reply | Report Abuse | Link to thisa) Your idea that a proton is an antielectron with changed rest mas cannot be true because protons are known (via deep scattering experiments) to have substructure (whether you choose to believe these are up and down quarks it does not matter) where as no scattering experiment on (anti)electrons show substructure.
b) Your idea that charge is somehow related to spin does not seem to hold any water either because particles like the photon and neutrinos (to give examples of both fermions and bosons) have spin, but are electrically neutral.
c) While I do not believe you will find a physicist who believes that the standard model is complete with no room for change, the idea that it is built on shaky ground seems extreme. The standard model has and continues to do an excellent job of predicting the majority particle experiments.
spillan3 - Thanks for responding. You seem to have replied to my comment (#10), although you did not identify me and there seems to be some confusion. I'll respond to your issues as best I can. I admit my comments are purely speculative: I did not discuss anything with any particle physicists.
Reply | Report Abuse | Link to thisa) I think you have meant to address deanlsinclair: he suggested that a proton is an antielectron with changed rest mass...
b) I suspect that photons do not have charge because their rest mass is zero. Neutrinos are another matter: my only guess might be that since their spin is fractional, unbound neutrinos have no charge?
c) Sorry, but I did not use the phrase 'shaky ground', although others did. Allow me to add another comment:
Isn't accurate predictive abilities overrated as proof of accurate representation of real physical processes? For example, Ptolemy of Alexandria was able to mathematically predict the motions of the planets in the sky as if they orbited the Earth. For hundreds of years, his successful formulas were regarded of proof that the Sun and planets orbited the Earth.
Classical Mechanics models gravitation as an imaginary attractive force. General Relativity does not describe a physical force producing the gravitational effect; it only represents the effect that the presence of mass imparts to a system of space-time coordinates. Quantum Mechanics does not support particle mass: matter collapses when a quantum gravitational effect is introduced.
While these models produce useful results simulating specific effects, they obviously do not adequately reflect the physical processes producing those effects. Quantum Mechanics even includes algorithms that do not represent any known physical processes, but are required for the model to produce accurate results. Experienced modelers used to call these 'fudge factors', referring to the practice of pushing a shot in a game of marbles.
Since these models do not represent physical processes but merely mimic their results, there is no conceptual basis for integrating them. As long as our objective is merely to calculate useful results for discrete problems, we have little chance of guessing a grand unified theory of everything. At least, not without a lot of 'fudging'.
"--- If antimatter had been created in the early universe, moving backwards in time, it would soon have preceded the big bang event."
Reply | Report Abuse | Link to thisThat would be true from our point of view, but if you were going the other direction in time you could make the same claim. So I think matter and antimatter proceed forward according to their own time arrow. If antimatter has opposite electrical charge I think it would also have opposite gravitational charge, meaning experience antigravity. So it's normally repelled by gravitational fields. If it was attractive it seems everything would soon annihilate. I don't know if Feynman realized this effect for gravitational fields as he did for e/m fields.
Note the above post should have been a reply.
Reply | Report Abuse | Link to thisThanks for reviving this interesting discussion!
Reply | Report Abuse | Link to thisThe Stanford Linear Accelerator (SLAC), for example, is an electron-positron collider. While electrons and positrons have opposing electrical charges, if positrons had anti-mass characteristics as well and produced antigravitational effects, I would not expect that they could be collided even in high velocity experiments.
An anti-mass quantum characteristic would seem to produce a distinctive response to the application of energy - perhaps even an 'anti-acceleration' effect! I'm no physicist, but I suspect that a negative mass characteristic would have been detected long ago in mass-spectrometry experiments, for example.
The term anti-gravity is most generally applied not to a negative gravitational effect but a hypothetical gravitationally neutral characteristic that effectively shields an object or region from the effects of gravitation. A truly negative anti-gravitational effect in Newtonian terms would produce the repellant force you mention rather than an attractive force; in relativistic terms perhaps it would produce a 'negative curvature' of spacetime, or something? Neither effect has ever been identified or even described in theory.
For positron-electron interactions the gravitational effects would be swamped out by the e/m forces, in theory. For neutrino-antineutrino detections I remember reading something about a deficiency of about 6% of anti-neutrinos, so gravity could have some effect here. In general CP violation might have some source in gravitational interactions. Anyway since most antimatter floats away so does the evidence. I don't know if Newton's laws are symmetrical in time direction but as I understand Feynman all physical laws are symmetrical in time so I don't think we need any additional laws for antimatter on the quantum level.
Reply | Report Abuse | Link to thisAs far as the shielding effect and negative curvature is concerned, we need an experimental test to answer: Does antimatter in the presence of matter increase or decrease the gravitational field. We know that the net effect of the combination in a container would be to decrease the total gravitational force. But how would the gravitational force between matter particles be effected, at least before one of the matter particles was annihilated by the antiparticle. In otherwords I'm not sure if the gravitational field is effected by whatever type of matter created it, it's only how the type of matter reacts to the curvature. Thanks for the response. I do know in the Feynman analogy of e/m, positrons react opposite to electrons for the same e/m field.
Reply | Report Abuse | Link to thisThanks. Please see: http://en.wikipedia.org/wiki/Positron
Reply | Report Abuse | Link to this"The positron or antielectron is the antiparticle or the antimatter counterpart of the electron. The positron has an electric charge of +1e, a spin of 1/2, and has the same mass as an electron."
The mass and spin of positrons are identical to those of electrons: only their electrical charges are in opposition. Since the effects of gravitation are proportional to aggregated mass, I don't see how there could be any distinction in antimatter's gravitational effects.
I imagine that Feynman's illustrations of antiparticle creations proceed backwards in quantum time only for the duration of the particle's emission and in relation to the emission event. If antiparticles actually existed in a backwardly flowing time at worldly scales, I think that would produce many problems for the persistence of positrons, for example, but I can only speculate.
I do not think there is a direct relation between electrical charge and the effects of mass, as in that case particles of matter that have negative charge, such as electrons, down, strange and bottom quarks, would produce antimass effects. Instead, the six types of quarks combine to produce nucleons with positive mass, as electrons, protons and neutrons form atoms of positive mass.
As I understand, it's presumed in general relativity that only positive mass produces the prescribed positive curvature of spacetime that in turn produces the observed gravitational effect on the motions of objects of mass. I would have to presume that any antimass effect would necessarily produce a negative curvature of spacetime and therefore negative gravitational effects: antimatter would in effect be repelled from each other and would offset the gravitational effects of matter.
Unfortunately your reference ignores the insight of Feynman and, perhaps, Einstein. Even Krauss. Certainly the idea of positive charge is so firmly ingrained in science that there is not much hope for building a logical foundation for physics in this generation, as I see it. Repeated crackpottery seems to be my latest rap. Unfortunate.
Reply | Report Abuse | Link to thisBut I do agree antimatter has the same mass as its matter counterpart. Also the same charge, except it acts opposite to matter, exactly as in the case of gravity and antigravity. I might suggest that as matter is attractive antimatter is mutually repulsive. So the stuff is extremely anti-social and forms no lasting bonds, you might say.
I see a fundamental logical misunderstanding of what a universe is. It comes from nothing and so on the whole it goes nowhere in space or time. If it came from something then that something would have to be part of the universe. Sort of caught between a rock and a hard place.
cont...
Reply | Report Abuse | Link to thisOf course there is expansion in space and similar expansion in time. Expansion in time requires two directions of travel, forward and reverse, just as expansion of space, that is if we go with Einstein's philosophy of treating space and time on an equal footing. Forced symmetry in all four dimensions. However much matter proceeds in forward time an equal amount must proceed in backwards time. Some people say "but you can't go back to before the big bang" if you say antimatter was created at the big bang. Right. But you could ask the same question from the point of view of antimatter. So neither direction of time is preferred and needs to go back to before the big bang. Both directions proceed from time=0 but proceed in opposite directions, similar to opposite directions in expanding spatial dimensions. If spatial expansion stopped, so time would stop moving in both directions. But that's a sort of moot question since I don't believe spatial expansion will ever stop until matter is eventually collected by the black holes, and one will eventually grow big enough to force another big bang. As a matter of fact it is probably happening everywhere in the larger universe, even right now. There is lots of room in Hilbert's hotel. It's interesting to speculate if there is one unique energy density forcing black holes to burst. In that case all universes would have similarities in their evolution, but each (theoretically) having different mass/energy distributions due to the uncertainty principle. That is, each seeing a different vision of the CMBR.
Well that's a lot on our plate for today. Should be plenty of fuel for speculation, or denial, or crackpottery charges anyway, which is about all you can do in the larger view of cosmology.