Naked Science Forum
Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: barneyboy on 02/01/2015 16:24:37
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Hi what percentage of the newly formed universe was left after matter and anti mater combined? is there any "proof" that it annihilates each other.
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List of unsolved problems in physics
https://en.wikipedia.org/wiki/Unsolved_problems_in_physics
So, go for it.
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Hi what percentage of the newly formed universe was left after matter and anti matter combined?
50%
Is there any "proof" that it annihilates each other.
Yes, annihilation (https://en.wikipedia.org/wiki/Electron%E2%80%93positron_annihilation). But there's a wrinkle, and it's a Lulu. See this article (http://www.cs.cdu.edu.au/homepages/jmitroy/workdesk/psatom.htm)? It's about positronium. Positronium is a short-lived "exotic atom". It isn't matter, or antimatter, it's both. OK? Now read this carefully:
"The Positronium (Ps) atom consists of an electron and a positron orbiting their mutual center of mass. To a first approximation it can be regarded as a sort of light hydrogen atom."
Positronium can be regarded a sort of light hydrogen. What does that suggest to you? You know what it suggests to me? That the electron is matter, and the proton is antimatter. People normally say the proton is matter and the antiproton is antimatter. But why? It's pure convention, nothing else. IMHO the "mystery of the missing antimatter" (https://en.wikipedia.org/wiki/Baryon_asymmetry) is like saying the men won the tennis match. Even though it was mixed doubles.
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what percentage of the newly formed universe was left after matter and anti matter combined?
50%
I am interested in where the 50% comes from?
Is this estimated from the observed ratio of matter to light in the universe, or some other source?
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People normally say the proton is matter and the antiproton is antimatter. But why? It's pure convention, nothing else.
I agree that the definition of matter & antimatter is purely convention.
As I understand it, the convention is this:
- "Matter" is that fairly stable stuff we see around us, that has been studied for centuries by chemists and alchemists.
- "Anti-matter" is very unstable stuff that was predicted by physicists (http://en.wikipedia.org/wiki/Positron#Theory) in the 20th century, and then finally discovered in high-energy nuclear collisions. It rapidly annihilates when it comes in contact with all that matter which the chemists have been studying for so long.
Since the Hydrogen we see throughout our galaxy is stable on human timescales, and composed of a proton and an electron, I must conclude from this convention that the proton and the electron and proton are both "matter".
The antiproton has a negative charge (like the electron). This universe would be most uncomfortable for creatures like us if the universe were composed of electrons and anti-protons (or positrons and protons). None of the familiar atoms or molecules could form.
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As I understand it, the convention is this:
- "Matter" is that fairly stable stuff we see around us,
•"Anti-matter" is very unstable stuff that
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Antimatter is as stable as matter, according to our present knowledge.
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lightarrow
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if matter and antimatter combine, what becomes of the energy's of the combined? and what becomes of the mass of the recently combined component's.
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what percentage of the newly formed universe was left after matter and anti matter combined?
50%
I am interested in where the 50% comes from?
I would also be interested in that data. I seem to remember reading somewhere that that percentage was much smaller than 50%. I have tried to find verification on that figure but have not yet been successful. If anyone can find credible information about this, please post it for our edification.
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From my investigation, it seems that shortly after the big bang, for every 10 billion particles of antimatter, there were 10 billion plus one of matter created. After annihilation takes place between antimatter and matter, that would only leave one particle in 20 billion left.
This works out to about: .0000000002%
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Sorry evan, I didn't see your post. I shall offer my belated reply:
I am interested in where the 50% comes from? Is this estimated from the observed ratio of matter to light in the universe, or some other source?
The latter. Put simply: in pair production in the early universe we produced electrons and positrons and protons and antiprotons. We now have baryon asymmetry and lepton asymmetry wherein only two out of the original four survive. That's 50%.
I agree that the definition of matter & antimatter is purely convention. As I understand it, the convention is this:
- "Matter" is that fairly stable stuff we see around us, that has been studied for centuries by chemists and alchemists.
- "Anti-matter" is very unstable stuff that was predicted by physicists (http://en.wikipedia.org/wiki/Positron#Theory) in the 20th century, and then finally discovered in high-energy nuclear collisions. It rapidly annihilates when it comes in contact with all that matter which the chemists have been studying for so long.
Since the Hydrogen we see throughout our galaxy is stable on human timescales, and composed of a proton and an electron, I must conclude from this convention that the proton and the electron and proton are both "matter".
There's an ambiguity here. On the one hand individual particles are labelled as matter and antimatter. On the other hand combinations of particles are labelled as matter and antimatter. The result of that is the mystery of the missing antimatter. It's a bit like watching a game of mixed-doubles tennis, then declaring that the men won, then musing about the mystery of the missing women. By hook or by crook, regardless of how evenly matched they were, one side was always going to win, and then we would call it matter. IMHO the situation is somewhat similar to enantiomers. We don't ponder the mystery of the missing L-glucose.
The antiproton has a negative charge (like the electron). This universe would be most uncomfortable for creatures like us if the universe were composed of electrons and anti-protons (or positrons and protons). None of the familiar atoms or molecules could form.
But if it was composed of antiprotons and positrons, all of the familiar atoms and molecules would form. And we would still have called it matter!
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I would also be interested in that data. I seem to remember reading somewhere that that percentage was much smaller than 50%. I have tried to find verification on that figure but have not yet been successful. If anyone can find credible information about this, please post it for our edification.
See above. The thing to remember is that the matter and antimatter was formed from pair production. Imagine that four zillion matter and antimatter particles were created over some period, during which time were also being destroyed by annihilation and by "melting" in a quark-gluon plasma. Now only two zillion survive.
From my investigation, it seems that shortly after the big bang, for every 10 billion particles of antimatter, there were 10 billion plus one of matter created.
Don't forget that the particles were created via pair production. If 10 billion particles of antimatter were created, 10 billion particles of matter were created.
After annihilation takes place between antimatter and matter, that would only leave one particle in 10 billion left. This works out to about: .0000000001%
The trick is to destroy more of one than the other. Have a look at melting particles in a quark-gluon plasma (https://www.google.co.uk/?gws_rd=ssl#q=quark-gluon+melt). If by chance you melt more of one type than the other, you get into a "stability tip" where the more common type gets more common.
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Anyway, if anybody asks me about the mystery of the missing antimatter, I say what mystery? Then when they say where has all the antimatter gone? I say this:
It hasn't gone anywhere. Weight by weight, you are 99.95% made of it.
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Anyway, if anybody asks me about the mystery of the missing antimatter, I say what mystery? Then when they say where has all the antimatter gone? I say this:
It hasn't gone anywhere. Weight by weight, you are 99.95% made of it.
ok, then. where has all the matter gone?
This isn't an issue of matter vs antimatter, which, as you have pointed out, is just a matter (no pun intended) of definition. The issue is parity: for each particle that we observe, where is the corresponding antiparticle?
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If in the early universe a vast amount of matter/antimatter annihilation occurred what has happened to all the resulting gamma radiation produced, has it degraded into the CMBR ?
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ok, then. where has all the matter gone? This isn't an issue of matter vs antimatter, which, as you have pointed out, is just a matter (no pun intended) of definition. The issue is parity: for each particle that we observe, where is the corresponding antiparticle?
It got melted. The early universe was a "maelstrom" of pair-production and annihilation. But if that's all you've got, you have to end up with the same number of electrons and positrons, and the same number of antiprotons and protons. You also have something akin to a "quark-gluon plasma" where you can melt particles and so destroy them without using an antiparticle. See this article (http://www.livescience.com/14748-quark-gluon-plasma-particle-soup-rhic.html). Note though that a quark-gluon plasma is something like pea soup: there are no actual peas in pea soup.
If in the early universe a vast amount of matter/antimatter annihilation occurred what has happened to all the resulting gamma radiation produced, has it degraded into the CMBR?
Some of the gamma radiation will have been recycled to make more matter. Maybe some became the CMBR, but that dates to something like 350,000 years after the big bang. AFAIK the pair production etc was before that.
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Thanks for the link about "melting." I still have some questions about this answer, though:
But by "melting" the hadrons into quark-gluon soup, they are not destroyed--it's just phase transition. Wouldn't they coalesce again into hadrons when it gets cold enough? Also it doesn't solve the matter-antimatter dilemma because protons break down into quarks and antiprotons break down into antiquarks... As far as I know quarks and antiquarks do not interconvert.
"Melting" also does not appear to have anything to do with leptons (electrons and positrons), so even if this solves the problem for hadrons, we still have a problem with leptons. No?
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John may have a point here.
http://en.wikipedia.org/wiki/Flavour_(particle_physics)
"Elementary particles are not eternal and indestructible. Unlike in classical mechanics, where forces only change a particle's momentum, the weak force can alter the essence of a particle, even an elementary particle. This means that it can convert one quark to another quark with different mass and electric charge, and the same for leptons. From the point of view of quantum mechanics, changing the flavour of a particle by the weak force is no different in principle from changing its spin by electromagnetic interaction, and should be described with quantum numbers as well. In particular, flavour states may undergo quantum superposition."
It all depends upon when the weak force became a separate entity. Quark modification could be the process by which an imbalance occurred. This cannot be verified by experiment however IMO.
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But by "melting" the hadrons into quark-gluon soup, they are not destroyed--it's just phase transition. Wouldn't they coalesce again into hadrons when it gets cold enough? Also it doesn't solve the matter-antimatter dilemma because protons break down into quarks and antiprotons break down into antiquarks... As far as I know quarks and antiquarks do not interconvert.
No, they melt. They are totally destroyed. There are no peas in pea soup, there are no quarks in a quark-gluon plasma. Note that gluons in ordinary hadrons are virtual (https://en.wikipedia.org/wiki/Gluon#Confinement). They aren't real. So there's no gluons in a quark-gluon plasma either. It's just this rather odd state of matter / energy. I think of it as something like one big high-pressure photon going nowhere. Don't forget that we can perform low-energy proton-antiproton annihilation to gamma photons. The cross section is something like 1%. The quarks and antiquarks are totally destroyed there too.
(https://www.thenakedscientists.com/forum/proxy.php?request=http%3A%2F%2Foutreach.atnf.csiro.au%2Feducation%2Fsenior%2Fcosmicengine%2Fimages%2Fcosmoimg%2Fpantipannihilation2.gif&hash=28620dcea1608024bf931e73034a99d8)
Image credit CSIRO, see http://www.atnf.csiro.au/outreach/education/senior/cosmicengine/bigbang.html
"Melting" also does not appear to have anything to do with leptons (electrons and positrons), so even if this solve the problem for hadrons, we still have a problem with leptons. No?
No. If you can destroy a proton you can destroy an electron.
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John may have a point here... the weak force can alter the essence of a particle, even an elementary particle...
Yep. I've talked to people about trick ways to get round conservation of charge. I think conservation of energy and conservation of momentum do hold, but charge is intimately related to electron spin. If you could contrive things such that an electron emitted two orthogonal photons, you'd be left with a photon. I don't think there's any way to do this in practice, but the general idea is something like this (http://upload.wikimedia.org/wikipedia/commons/thumb/d/d2/Right_hand_rule_cross_product.svg/507px-Right_hand_rule_cross_product.svg.png).
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Anyway, if anybody asks me about the mystery of the missing antimatter, I say what mystery? Then when they say where has all the antimatter gone? I say this:
It hasn't gone anywhere. Weight by weight, you are 99.95% made of it.
Ah! So the other 0.05% of me is made of Holy Spirit, isnt'it?
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lightarrow
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No. Matter.
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No. Matter.
You were starting to impress me and now you've blown it again.
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No. Matter.
You were starting to impress me and now you've blown it again.
I concur.........................
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No. Matter.
This belongs in the New Theories Section.
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No it doesn't. What belongs in the trashcan is the definition of matter and antimatter as both individual particles and combinations of particles. What doesn't, is knowing that positronium is an exotic atom that's made up of both matter and antimatter. And that to a first approximation it can be regarded as a sort of light hydrogen atom. (http://www.cs.cdu.edu.au/homepages/jmitroy/workdesk/psatom.htm)
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Positronium can be regarded as a "sort of light hydrogen" because it involves two subatomic particles of equal and opposite charges interacting. This can be modeled by the same type of Schrödinger equations used for hydrogen, only substituting the mass (or reduced mass) terms. You can also make an exotic hydrogen-like atom using a muon and proton (or muon and positron!).
It does not follow (IMO) that protons are antimatter.
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Positronium can be regarded as a "sort of light hydrogen" because it involves two subatomic particles of equal and opposite charges interacting. This can be modeled by the same type of Schrödinger equations used for hydrogen, only substituting the mass (or reduced mass) terms. You can also make an exotic hydrogen-like atom using a muon and proton (or muon and positron!).
It does not follow (IMO) that protons are antimatter.
I also concur.......................
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No. Matter.
I may be missing the point, but you seem to be changing definitions without proposing a change in how particles actually interact, but then concluding there is a grave error in physics for what is essentially a symantic difference.
The broad categories of matter and anti-matter are useful for brevity of expression, but the only thing that really matters (pardon me) is the interaction between a particle and its specific anti-particle. An electron will never annihilate with a proton. Nor will it annihilate with an anti-proton. It will only annihilate with a positron. Similarly a proton will only annihilate with an anti-proton.
Physicists have traditionally called both electrons and protons (and neutrons, although you don't bring them up)matter. This is a simple expediency, since these are the particles that make up the world around us. We've called this stuff "matter" long before anti-matter was conceived of by the human mind. Anti-matter is the catch-all term for the antiparticles of the ones we call matter.
Unless you are proposing new mechanisms for how the particles actually interact, however, swapping the matter and anti-matter labels on protons and anti-protons is simply that: swapping labels. It has the disadvantage of being linguistically confusing, but it does not in itself have any physical content.
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I may be missing the point, but you seem to be changing definitions without proposing a change in how particles actually interact, but then concluding there is a grave error in physics for what is essentially a symantic difference.
I'm not changing definitions so much as pointing out an ambiguity in the definitions. We say hydrogen is matter by convention, that's all. Then we say the electron is matter and the positron is antimatter, and that positronium is both, but it's like light hydrogen. Problem. The solution is to say hydrogen is both. Think mixed-doubles in tennis. Hydrogen is both, antihydrogen is both. Each consists of a particle and an antiparticle.
The broad categories of matter and anti-matter are useful for brevity of expression, but the only thing that really matters (pardon me) is the interaction between a particle and its specific anti-particle. An electron will never annihilate with a proton. Nor will it annihilate with an anti-proton. It will only annihilate with a positron. Similarly a proton will only annihilate with an anti-proton.
Nothing wrong with that. But the electron and the proton move towards one another. It's like they "want" to annihilate, but they don't "fit".
Physicists have traditionally called both electrons and protons (and neutrons, although you don't bring them up) matter. This is a simple expediency, since these are the particles that make up the world around us. We've called this stuff "matter" long before anti-matter was conceived of by the human mind. Anti-matter is the catch-all term for the antiparticles of the ones we call matter.
Yes, it stems from mere convention. Only we never stop hearing about the mystery of the missing antimatter, but nobody gets concerned about the mystery of the missing L-glucose.
Unless you are proposing new mechanisms for how the particles actually interact
No, not at all.
however, swapping the matter and anti-matter labels on protons and anti-protons is simply that: swapping labels. It has the disadvantage of being linguistically confusing, but it does not in itself have any physical content.
It isn't linguistically confusing. What's confusing is that ambiguity that arose from mere convention. Get rid of that, and the mystery goes away.
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No, the mystery does not go away. The "mystery of the missing antimatter" is shorthand for the individual mysteries of the missing positrons, the missing antiprotons, etc. Relabeling antiprotons as "antimatter" does not make it less mysterious that we've got a lot of protons and a lot of electrons and apparently negligible amounts of positrons and antiprotons.
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You've missed the mixed doubles nuance. No matter how evenly matched they are, one side wins the game. Until one side wins, our universe can't sustain planets or stars or galaxies or life or anything. Then whichever side won, we call it matter.
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No. If they are exactly evenly matched, then it is a tie.
Are you saying
(1) It is a tie, but we just happen to have electrons and protons in this part of the universe but they are all balanced by positrons and antiprotons somewhere else? This raises the problem of why we never see evidence of clumps made of electrons and protons (like what we live in) running into clumps made of positrons and antiprotons.
(2) It is not a tie. There actually were more electrons than positrons and protons than antiprotons. This raises the problem of how this happens when the physical laws governing them seem to be symmetrical.
or
(3) Something else. (If so, please explain, because I sincerely can't think of a third option between "it is a tie" and "it isn't a tie.")
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You've missed the mixed doubles nuance. No matter how evenly matched they are, one side wins the game. Until one side wins, our universe can't sustain planets or stars or galaxies or life or anything. Then whichever side won, we call it matter.
I think we are all missing the mixed doubles analogy... Unless you can propose a way to form an electron and a proton without creating an antielectron and an antiproton, I don't see what it has to do with anything.
...Hydrogen is both, antihydrogen is both. Each consists of a particle and an antiparticle...
...But the electron and the proton move towards one another. It's like they "want" to annihilate, but they don't "fit".
Each is composed of a positively charged particle and a negatively charged particle. This has little to do with the matter/antimatter issue
nobody gets concerned about the mystery of the missing L-glucose.
Well, since there is a clear biological mechanism that produces only the one form of glucose without necessitating the other enantiomer to be created, there is no mystery. There is, however, much debate as to how (chemical) symmetry was broken in prebiotic history--why only one enantiomer of ribose? or only the one enantiomer of each of the amino acids? Some have gone so far as to claim that circularly polarized UV light from a rapidly spinning star selectively decomposed one enantiomer over the other (tipping the balance, then autocatalysis amplified the difference).
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No. If they are exactly evenly matched, then it is a tie.
No it isn't, because there's a tie breaker.
Are you saying
(1) It is a tie, but we just happen to have electrons and protons in this part of the universe but they are all balanced by positrons and antiprotons somewhere else?
No. We have electrons and positrons in the universe. The baryon asymmetry is balanced by the lepton asymmetry.
This raises the problem of why we never see evidence of clumps made of electrons and protons (like what we live in) running into clumps made of positrons and antiprotons.
If there were clumps of say, antihydrogen, we'd see it getting annihilated. The sky would be ablaze with hard gamma radiation.
(2) It is not a tie. There actually were more electrons than positrons and protons than antiprotons. This raises the problem of how this happens when the physical laws governing them seem to be symmetrical.
It isn't a tie because whilst the same number of electrons and positrons get produced, more positrons got destroyed by chance "melting" in the central quark-gluon plasma*. Then the slight excess of electrons led to a "stability tip". It's a bit like games where you get a slight advantage then magnify it and win the game. I don't know if you've ever played Go, but imagine that if I capture your black counters they get turned into black counters and white counters. Then I capture your black counters, and we repeat ad infinitum. It's ditto for the protons and the antiprotons, plus there's a relationship between electron and protons and positrons and antiprotons.
(3) Something else. (If so, please explain, because I sincerely can't think of a third option between "it is a tie" and "it isn't a tie.")
It isn't a tie.
* see this: http://www.livescience.com/14748-quark-gluon-plasma-particle-soup-rhic.html
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(2) It is not a tie. There actually were more electrons than positrons and protons than antiprotons.
This agrees with the information I have found.
For every 10 billion positrons, there were 10 billion and one electrons. After annihilation takes place, one electron remains. Same story for the antiprotons and protons.
Result; One particle of matter remains in each case while 20 billion annihilate. This is where all the antimatter has gone along with an equal amount of regular matter. Leaving approx. just .00000000005% let over along with the photon radiation we observe presently.
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I think we are all missing the mixed doubles analogy... Unless you can propose a way to form an electron and a proton without creating an antielectron and an antiproton, I don't see what it has to do with anything.
I can't. But there is a way to destroy the antielectron and the antiproton. You melt 'em.
Each is composed of a positively charged particle and a negatively charged particle. This has little to do with the matter/antimatter issue
It has everything to do with it. What's the difference between a particle and its antiparticle? It's mass. No. They have a different chirality. And if you know anything about TQFT and topological charge, you'll know that they have their opposite charge because they have the opposite chirality.
Well, since there is a clear biological mechanism that produces only the one form of glucose without necessitating the other enantiomer to be created, there is no mystery.
Yes there is. Why don't we see both right and left-handed glucose in nature? By the way you know that L-glucose is just one half of a lock-and-key arrangement? (https://www.google.co.uk/?gws_rd=ssl#q=glucose+lock+and+key) Positronium can be viewed as something similar. And so can hydrogen but there the key won't turn.
There is, however, much debate as to how (chemical) symmetry was broken in prebiotic history--why only one enantiomer of ribose? or only the one enantiomer of each of the amino acids? Some have gone so far as to claim that circularly polarized UV light from a rapidly spinning star selectively decomposed one enantiomer over the other (tipping the balance, then autocatalysis amplified the difference).
Sounds reasonable. See what I said above about a "stability tip" where a slight advantage gets magnified.
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For every 10 billion positrons, there were 10 billion and one electrons...
It doesn't work. Electrons and positrons are produced by pair production. If you create 10 billion electrons, you create 10 billion electrons. Then when you annihilate 10 billion electrons with 10 billion electrons, you're left with none of the above. You have to have that "melting" in the quark gluon plasma or your universe is a fail.
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Ok... two questions:
1) Are you saying that antielectrons and antiprotons are more likely to melt than their respective anti-articles? Or is it that, somehow, by random chance a slight imbalance manifested?
2) I understand how autocatalysis works in chemistry. How does the imbalance of matter vs antimatter magnify itself? (this is a question of ignorance, not a challenge)
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For every 10 billion positrons, there were 10 billion and one electrons...
It doesn't work.
Fox news has recently reported that a team working at Cern's LHC has discovered a particle that decays unevenly into matter and antimatter. This would account for the imbalance and allow one case to dominate allowing for the mystery of the missing antimatter.
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For every 10 billion positrons, there were 10 billion and one electrons...
It doesn't work.
Fox news has recently reported that a team working at Cern's LHC has discovered a particle that decays unevenly into matter and antimatter. This would account for the imbalance and allow one case to dominate allowing for the mystery of the missing antimatter.
Do you have a link?
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If correct this is very intriguing.
http://www.telegraph.co.uk/news/science/large-hadron-collider/10016339/Large-Hadron-Collider-results-hint-at-where-all-the-antimatter-has-gone.html
["As a consequence of a very tiny difference between antimatter and matter, it meant that the matter survived while the antimatter did not.
“The universe is made up of a billionth of the matter created in the big bang – so we are the billionth that was left over after the antimatter destroyed the rest.”
Previous experiments around the world have shown signs of the CP Violation in three types of particles known as mesons.
This latest finding from CERN, which is published in the journal Physical Review Letters, shows the CP Violation in a fourth type of meson, made of smaller particles known as Beauty quarks and Strange quarks.
LHCb allowed the scientists at CERN to track how these mesons decayed as they were flung out from the explosions created by the particle collisions.
They found that around one in four of the antimatter versions of these Bs mesons decayed more readily than their matter counterparts.]
This seems to indicate that it is a difference in the quark types. However if you read to the very bottom this is not the solution to the mystery but only part of a solution.
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For every 10 billion positrons, there were 10 billion and one electrons...
It doesn't work.
Fox news has recently reported that a team working at Cern's LHC has discovered a particle that decays unevenly into matter and antimatter. This would account for the imbalance and allow one case to dominate allowing for the mystery of the missing antimatter.
Do you have a link?
I just typed into Yahoo: "Where is all the missing antimatter?"
I believe it was the first article in the list. I resist copying and pasting articles because of copyright infringement worries.
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* see this: http://www.livescience.com/14748-quark-gluon-plasma-particle-soup-rhic.html
So I read the linked article. The quark-gluon plasma doesn't do what you want it to.
First off, it has nothing to do with electrons. Electrons are not composed of quarks. Indeed, most physicists believe that electrons aren't composed of anything smaller. (Every so often I hear about proposals of benefits of considering the electron a composite particle, but I'm not aware of any that have stuck.) So the electrons aren't going to melt. Even if the quark-gluon plasma provided an answer for the lack of anti-protons, it wouldn't provide one for the lack of positrons.
Second, the quark-gluon plasma just pushes the matter/antimatter problem back one step further, rather than getting rid of it. Quarks have anti-particles as well. Indeed, if they didn't, then the particles they made up wouldn't have them either. A proton is made up of two up quarks and a down quark. An anti-proton is made of two anti-ups and an anti-down. So the question in the early universe is "Why are there more quarks than anti-quarks?"
So we're back to a choice between what I described above as options (1) and (2). As others have been pointing out, the bulk of research has centered around option (2), that there was a real imbalance. There does seem to be some progress in that recently, as the material mentioned by Ethos_ and the article linked by jeffreyH show.
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* see this: http://www.livescience.com/14748-quark-gluon-plasma-particle-soup-rhic.html
So I read the linked article. The quark-gluon plasma doesn't do what you want it to.
First off, it has nothing to do with electrons. Electrons are not composed of quarks. Indeed, most physicists believe that electrons aren't composed of anything smaller. (Every so often I hear about proposals of benefits of considering the electron a composite particle, but I'm not aware of any that have stuck.) So the electrons aren't going to melt. Even if the quark-gluon plasma provided an answer for the lack of anti-protons, it wouldn't provide one for the lack of positrons.
Second, the quark-gluon plasma just pushes the matter/antimatter problem back one step further, rather than getting rid of it. Quarks have anti-particles as well. Indeed, if they didn't, then the particles they made up wouldn't have them either. A proton is made up of two up quarks and a down quark. An anti-proton is made of two anti-ups and an anti-down. So the question in the early universe is "Why are there more quarks than anti-quarks?"
So we're back to a choice between what I described above as options (1) and (2). As others have been pointing out, the bulk of research has centered around option (2), that there was a real imbalance. There does seem to be some progress in that recently, as the material mentioned by Ethos_ and the article linked by jeffreyH show.
Excellent analysis my friend............................
I think an even better understanding of this phenomenon will precipitate from the experiments being preformed at Cern. We stand to gather new information as the team there steps up the LHC to maximum power in the coming months. I'm excited to hear about the forth coming discoveries that will shortly come to light.
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Ok... two questions:
1) Are you saying that antielectrons and antiprotons are more likely to melt than their respective anti-articles? Or is it that, somehow, by random chance a slight imbalance manifested?
The latter. But I don't actually know this. Have a look at this article (http://www2.warwick.ac.uk/newsandevents/pressreleases/galaxy_sized_twist/) featuring Mark Hadley at Warwick talking about rotation causing a frame-dragging that then causes particles and antiparticles to behave slightly differently.
2) I understand how autocatalysis works in chemistry. How does the imbalance of matter vs antimatter magnify itself? (this is a question of ignorance, not a challenge)
I don't actually know, but I envisage it needs something like a cooking-pot process. If I engineer a chance situation where there's more electrons & protons than positrons & antiprotons, the positrons and antiprotons all get destroyed. Our cooking pot consists of a hot lower zone, plus a warm zone, plus a cold-zone "skin" of hydrogen on top. Electrons and positrons and protons and antiprotons get created in the warm zone. If they stay there they can get destroyed via annihilation. If they go down into the hot zone they get destroyed by melting. If a lone antiproton comes up from warm zone it tends to interact with the electron on the outside of a hydrogen atom in the fairly massive skin, and tends to get repelled back towards the hot zone. If it meets up with a (lightweight) positron coming the other way it drags it into the hot zone and they both get melted. If a proton comes up from the warm zone it doesn't get repelled back down, and can hang around until it meets up with an electron. Then the skin gets thicker. If a positron comes up the skin takes a hit, but then an electron comes up and fixes the damage. Overall the skin gets thicker and thicker as the pot cools down, and in the end the pan is nicely full of "matter".
Note though that electrons and positrons have the opposite chirality, as do protons and antiprotons. Maybe there's some similarity with autocatalysis. And the Mark Hadley might be like stirring the pot such that it's hydrogen to the top, and antihydrogen to the bottom. I don't know for sure, but whatever it is, it can't be magic.
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So I read the linked article. The quark-gluon plasma doesn't do what you want it to. First off, it has nothing to do with electrons. Electrons are not composed of quarks.
Nor is a quark-gluon plasma. A quark-gluon plasma isn't a mess of quarks and gluons buzzing around. Hadrons melt in it. They don't split up into quarks and gluons. And if a hadron melts, an electron will melt too. Note that gluons in ordinary hadrons are virtual anyway, see this (https://en.wikipedia.org/wiki/Gluon#Confinement). Quarks are just partons. Parts.
Indeed, most physicists believe that electrons aren't composed of anything smaller. (Every so often I hear about proposals of benefits of considering the electron a composite particle, but I'm not aware of any that have stuck.) So the electrons aren't going to melt.
Yes they are. If a proton cannot maintain its integrity, nor can an electron. See this (http://home.web.cern.ch/about/physics/heavy-ions-and-quark-gluon-plasma) about heavy-ion collisions where everything “melts” into a quark-gluon plasma.
Even if the quark-gluon plasma provided an answer for the lack of anti-protons, it wouldn't provide one for the lack of positrons.
Not on its own. See the cooking-pot analogy above.
Second, the quark-gluon plasma just pushes the matter/antimatter problem back one step further, rather than getting rid of it. Quarks have anti-particles as well. Indeed, if they didn't, then the particles they made up wouldn't have them either. A proton is made up of two up quarks and a down quark. An anti-proton is made of two anti-ups and an anti-down. So the question in the early universe is "Why are there more quarks than anti-quarks?"
We've never seen a free quark. Best not to worry about them.
So we're back to a choice between what I described above as options (1) and (2). As others have been pointing out, the bulk of research has centered around option (2), that there was a real imbalance. There does seem to be some progress in that recently, as the material mentioned by Ethos_ and the article linked by jeffreyH show.
IMHO this is a bit of a red herring. The Bs meson is comprised of a bottom antiquark and a strange quark, so it isn’t really matter or antimatter, it’s both. And it oscillates into its own antiparticle and back in about 18 picoseconds, so again it’s both. And it lasts for a circa 1.5 x 10^-13 seconds. See what Professor Chris Parkes said: the difference between the matter and antimatter particles they had seen was still too small to fully explain the dominance of matter today.
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So I read the linked article. The quark-gluon plasma doesn't do what you want it to. First off, it has nothing to do with electrons. Electrons are not composed of quarks.
Nor is a quark-gluon plasma. A quark-gluon plasma isn't a mess of quarks and gluons buzzing around. Hadrons melt in it. They don't split up into quarks and gluons. And if a hadron melts, an electron will melt too. Note that gluons in ordinary hadrons are virtual anyway, see this (https://en.wikipedia.org/wiki/Gluon#Confinement). Quarks are just partons. Parts.
Followed your first link. Within it was the following sentence which directly contradicts your assertion about what a quark-gluon plasma is.
"Beyond the normal phase of QCD (at extreme temperatures and pressures), quark gluon plasma forms. In such a plasma there are no hadrons; quarks and gluons become free particles." (emphasis added)
Indeed, most physicists believe that electrons aren't composed of anything smaller. (Every so often I hear about proposals of benefits of considering the electron a composite particle, but I'm not aware of any that have stuck.) So the electrons aren't going to melt.
Yes they are. If a proton cannot maintain its integrity, nor can an electron. See this (http://home.web.cern.ch/about/physics/heavy-ions-and-quark-gluon-plasma) about heavy-ion collisions where everything “melts” into a quark-gluon plasma.
Followed your second link. It makes no mention of electrons or positrons, so I don't see how it supports your assertion.
Protons are believed to be composite particles. Electrons are not believed to be composite particles. The dissolution of protons under high energy conditions does not carry any implications about what happens to electrons.
At this point, I'm bowing out. Your main point has basis neither in the physics I learned in graduate school nor in the references you claim support it. I'm at the limits of my ability to recast my explanations in new words that will be any clearer or more helpful than what I've said up to this point.
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From the link provided by JohnDuffield (http://home.web.cern.ch/about/physics/heavy-ions-and-quark-gluon-plasma)
"...such as gold or lead nuclei. In these heavy-ion collisions the hundreds of protons and neutrons in two such nuclei smash into one another at energies of upwards of a few trillion electronvolts each. This forms a miniscule fireball in which everything “melts” into a quark-gluon plasma.
The fireball instantly cools, and the individual quarks and gluons (collectively called partons) recombine into a blizzard of ordinary matter that speeds away in all directions. The debris contains particles such as pions and kaons, which are made of a quark and an antiquark; protons and neutrons, made of three quarks; and even copious antiprotons and antineutrons, which may combine to form the nuclei of antiatoms as heavy as helium..."
I still don't think this applies to electrons. They say "everything melts", but "everything" is still just nuclei, no electrons involved. Are there studies where they use only partially ionized nuclei?
It would appear that this soup does allow for the conversion of quarks into antiquarks, as normal matter is melted, and then as it cools there is a distribution of combinations of quarks and antiquarks. The article alludes to study of this distribution. What is known about the distribution?
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At this point, I'm bowing out. Your main point has basis neither in the physics I learned in graduate school nor in the references you claim support it. I'm at the limits of my ability to recast my explanations in new words that will be any clearer or more helpful than what I've said up to this point.
I agree. I think if John has a new theory outside of the mainstream, he should post it in the New Theories Section. This Section of the forum is dedicated to main stream physics.
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We've never seen a free quark. Best not to worry about them.
Why?
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At this point, I'm bowing out. Your main point has basis neither in the physics I learned in graduate school nor in the references you claim support it. I'm at the limits of my ability to recast my explanations in new words that will be any clearer or more helpful than what I've said up to this point.
I agree. I think if John has a new theory outside of the mainstream, he should post it in the New Theories Section. This Section of the forum is dedicated to main stream physics.
This is not an easy branch of physics. It needs a theory backed by mathematics that can then be used to make predictions which can be tested. What worries me about what John says is that he feels that you can neglect certain aspects, in other words not to worry about them. You can't do that otherwise you are not taking everything into consideration.
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This is not an easy branch of physics. It needs a theory backed by mathematics that can then be used to make predictions which can be tested. What worries me about what John says is that he feels that you can neglect certain aspects, in other words not to worry about them. You can't do that otherwise you are not taking everything into consideration.
Exactly..............You can't operate honestly if you only consider those issues that fit your favorite schemes. Science is about experiment and observation, if those findings don't fit in nicely with your preferred views, the good scientist will simply have to change his outlook. Dismissing a detail here and there just because it doesn't fit your theory is bad science.
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Followed your first link. Within it was the following sentence which directly contradicts your assertion about what a quark-gluon plasma is.
"Beyond the normal phase of QCD (at extreme temperatures and pressures), quark gluon plasma forms. In such a plasma there are no hadrons; quarks and gluons become free particles." (emphasis added)
That's wrong. It's sloppy popscience reporting. Go and ask elsewhere whether the gluons in ordinary hadrons are virtual and whether electrons melt in a quark-gluon plasma.
Followed your second link. It makes no mention of electrons or positrons, so I don't see how it supports your assertion.
An ion contains electrons! Everything melts!
Protons are believed to be composite particles. Electrons are not believed to be composite particles. The dissolution of protons under high energy conditions does not carry any implications about what happens to electrons.
The dissolution of ions does! There's something like 78 electrons in a gold ion.
At this point, I'm bowing out. Your main point has basis neither in the physics I learned in graduate school
Go and follow up on what I said. Do not think you learned everything there is to learn at graduate school, such that you reject anything that is contrary to what you think you know.
nor in the references you claim support it. I'm at the limits of my ability to recast my explanations in new words that will be any clearer or more helpful than what I've said up to this point.
If you don't believe what I'm telling you, go and ask elsewhere, and do your own research.
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I still don't think this applies to electrons. They say "everything melts", but "everything" is still just nuclei, no electrons involved. Are there studies where they use only partially ionized nuclei?
Yes, gold ions, lead ions. See this RHIC article (http://www.bnl.gov/rhic/news2/news.asp?a=1074&t=pr). It's written for the general public, but look closely and you can spot stuff like this:
"This liquid matter has been described as nearly “perfect” in the sense that it flows with almost no frictional resistance, or viscosity. Such a “perfect” liquid doesn’t fit with the picture of “free” quarks and gluons physicists had previously used to describe QGP."
It would appear that this soup does allow for the conversion of quarks into antiquarks, as normal matter is melted, and then as it cools there is a distribution of combinations of quarks and antiquarks.
The point to remember is that this "soup" is like pea soup. There are no peas in pea soup.
The article alludes to study of this distribution. What is known about the distribution?
I don't know offhand.
We've never seen a free quark. Best not to worry about them.
Why?
Because they're "partons". They're just parts. Have a look at TQFT.
I agree. I think if John has a new theory outside of the mainstream, he should post it in the New Theories Section. This Section of the forum is dedicated to main stream physics.
I don't have a new theory outside of the mainstream. The QGP isn't like what the popscience articles say. A proton contains no real gluons. We melt heavy ions to create a QGP. It isn't my fault if the simplified reporting doesn't say what happened to the electrons. And nor is it my fault that antimatter is used to label both individual particles and pairs of particles. It isn't some new theory to point out the ambiguity and the mere convention and how positronium is like light hydrogen, and that baryon asymmetry is matched by lepton asymmetry.
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Just to be balanced on the topic of virtual gluons.
http://en.wikipedia.org/wiki/Gluon
[Since gluons themselves carry color charge, they participate in strong interactions. These gluon-gluon interactions constrain color fields to string-like objects called "flux tubes", which exert constant force when stretched. Due to this force, quarks are confined within composite particles called hadrons. This effectively limits the range of the strong interaction to 10−15 meters, roughly the size of an atomic nucleus. Beyond a certain distance, the energy of the flux tube binding two quarks increases linearly. At a large enough distance, it becomes energetically more favorable to pull a quark-antiquark pair out of the vacuum rather than increase the length of the flux tube.
Gluons also share this property of being confined within hadrons. One consequence is that gluons are not directly involved in the nuclear forces between hadrons. The force mediators for these are other hadrons called mesons.
Although in the normal phase of QCD single gluons may not travel freely, it is predicted that there exist hadrons that are formed entirely of gluons — called glueballs. There are also conjectures about other exotic hadrons in which real gluons (as opposed to virtual ones found in ordinary hadrons) would be primary constituents. Beyond the normal phase of QCD (at extreme temperatures and pressures), quark gluon plasma forms. In such a plasma there are no hadrons; quarks and gluons become free particles.]
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Followed your second link. It makes no mention of electrons or positrons, so I don't see how it supports your assertion.
An ion contains electrons! Everything melts!
I still don't think this applies to electrons. They say "everything melts", but "everything" is still just nuclei, no electrons involved. Are there studies where they use only partially ionized nuclei?
Yes, gold ions, lead ions. See this RHIC article (http://www.bnl.gov/rhic/news2/news.asp?a=1074&t=pr).
I followed the link, and it also defines the "gold ions" as gold nuclei. An ion is a charged particle, and doesn't necessarily have any electrons. For instance, the H+ ion is just a proton. While most gold ions encountered in chemistry are Au+, or Au3+ (having 78 and 76 electrons, respectively), high energy physics is usually done with just the nuclei (Au79+). It takes several keV to ionize a gold atom completely, but these experiments are usually on the GeV or TeV energy scale, easily stripping all of the electrons away from the nucleus.
I will try to find a publicly-available, non-popsci article on the matter later today, but I am positive (no pun intended) that there were no electrons involved in these studies.
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I haven't found any publicly available articles yet, but I read a good review on quark gluon soups from Nature (Braun-Munzinger and Stachel, 2007). It confirms that only nuclei (fully ionized atoms) are used, and only fairly large nuclei at that (it looks like silicon is the lightest element they got to work). They were unable to get single protons or single electrons to "melt" because you need extrememly high quark density, which is much easier when starting with nuclei that contain several nucleons.
It looks like they needed to impart at least 10 GeV to each nucleus to get them to melt.
Also, with regards to the "pea soup having no peas," according to this review, quark gluon soup is made of quarks and gluons just as much as hadrons are--there are no isolated quarks, they are all interacting, but the interaction is weaker at such high densities, so the phase has liquid properties instead of solid properties. As the soup cools, it re-hadronizes.
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Also, with regards to the "pea soup having no peas," according to this review, quark gluon soup is made of quarks and gluons just as much as hadrons are--there are no isolated quarks, they are all interacting, but the interaction is weaker at such high densities, so the phase has liquid properties instead of solid properties. As the soup cools, it re-hadronizes.
Instead of "pea soup having no peas" this suggests something more like quicksand. Where Quarks and gluons represent the particles of the sand in a densely packed arrangement similar to how one might view the physical characteristics of a fluid like quicksand.
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Note this from Jeffrey's quote above:
"...There are also conjectures about other exotic hadrons in which real gluons (as opposed to virtual ones found in ordinary hadrons) would be primary constituents..."
There are no real gluons in a proton. Then when you melt a proton to make a quark-gluon plasma, there are still no real gluons. So a quark-gluon plasma cannot be a mixture of discrete quarks and gluons. It can't be like sand. But imagine you heated some sand in a crucible, such that all the grains melted. I'm saying that a quark-gluon-plasma (QGP) is like melted sand, not sand.
By the way, I stand corrected on the gold ions. See Wikipedia (https://en.wikipedia.org/wiki/Relativistic_Heavy_Ion_Collider#The_accelerator) where you can read this:
"As an example, gold nuclei leaving the EBIS have a kinetic energy of 2 MeV per nucleon and have an electric charge Q = +32 (32 of 79 electrons stripped from the gold atom). The particles are then accelerated by the Booster Synchrotron to 100 MeV per nucleon, which injects the projectile now with Q = +77 into the Alternating Gradient Synchrotron (AGS), before they finally reach 8.86 GeV per nucleon and are injected in a Q = +79 state (no electrons left) into the RHIC storage ring..."
However I will insist that if you threw an electron into a QGP, it too would melt.