Why Do Matter Particles Come in Threes? A Physics Titan Weighs In. (quantamagazine.org) 48
Three progressively heavier copies of each type of matter particle exist, and no one knows why. A new paper by Steven Weinberg takes a stab at explaining the pattern. From a report: Electrons and two types of quarks, dubbed "up" and "down," mix in various ways to produce every atom in existence. But puzzlingly, this family of matter particles -- the up quark, down quark and electron -- is not the only one. Physicists have discovered that they make up the first of three successive "generations" of particles, each heavier than the last. The second- and third-generation particles transform into their lighter counterparts too quickly to form exotic cats, but they otherwise behave identically. It's as if the laws of nature were composed in triplicate. "We don't know why," said Heather Logan, a particle physicist at Carleton University. In the 1970s, when physicists first worked out the Standard Model of particle physics -- the still-reigning set of equations describing the known elementary particles and their interactions -- they sought some deep principle that would explain why three generations of each type of matter particle exist. No one cracked the code, and the question was largely set aside.
Now, though, the Nobel Prize-winning physicist Steven Weinberg, one of the architects of the Standard Model, has revived the old puzzle. Weinberg, who is 86 and a professor at the University of Texas, Austin, argued in a recent paper in the journal Physical Review D that an intriguing pattern in the particles' masses could lead the way forward. "Weinberg's paper is a bit of lightning in the dark," said Anthony Zee, a theoretical physicist at the University of California, Santa Barbara. "All of a sudden a titan in the field is suddenly working again on these problems." "I'm very happy to see that he thinks it's important to revisit this problem," said Mu-Chun Chen, a physicist at the University of California, Irvine. Many theorists are ready to give up, she said, but "we should still be optimistic."
Now, though, the Nobel Prize-winning physicist Steven Weinberg, one of the architects of the Standard Model, has revived the old puzzle. Weinberg, who is 86 and a professor at the University of Texas, Austin, argued in a recent paper in the journal Physical Review D that an intriguing pattern in the particles' masses could lead the way forward. "Weinberg's paper is a bit of lightning in the dark," said Anthony Zee, a theoretical physicist at the University of California, Santa Barbara. "All of a sudden a titan in the field is suddenly working again on these problems." "I'm very happy to see that he thinks it's important to revisit this problem," said Mu-Chun Chen, a physicist at the University of California, Irvine. Many theorists are ready to give up, she said, but "we should still be optimistic."
Why? (Score:2)
"describing the known elementary particles and their interactions "
Elementary, my dear Watson.
Re:Why? (Score:4, Informative)
Nothing less elementary than the mass of elementary particles. There's no solid quantitative theory explaining their rest mass. The mass of the larger quarks isn't even known very accurately. We know qualitatively that their rest mass comes from the Higgs field, but not why any given particle has the mass it does. That's one of many reasons no one is satisfied with the Standard Model.
Of course, most of the mass of the proton and neutron, and thus of all familiar matter, comes from the strong force binding energy, and that's understood fairly well. OTOH, most of the matter in the universe is dark matter, and no one has a clue about that. It used to be a reasonable assumption that dark matter was also coupled with the Higgs field, and thus to have rest mass that way, as it was thought to interact via the weak force. However, early experiments designed to detect dark matter haven't, and so the ideas about the weak force are a bit dubious now.
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The higgs field explains the rest mass of the W and Z bosons through spontaneous symmetry breaking, however this mechanism can't explain the rest mass of fermions. One theory is that a fermion field interacts with the higgs field through a yet unknown coupling.
Maybe I'm not parsing this right. I mean, everything's "a theory", but I thought the theory that the mass of fermion fields came from coupling with the Higgs field, the Yukawa interaction, was the accepted explanation of the standard model.
(Imagine unicode here): g * psi-bar * phi * psi
Where psi is the fermion field and phi is the Higgs scalar. Or is this a case of "the math works, but we still don't know the mechanism actually exists"?
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Until we can find some evidence of the yukawa interaction between the Higgs field and fermion field this theory remains in the second camp. It remains possible, however unlikely that fermions get some or all of their res
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It always remains possible that any theory is wrong. Not very interesting. The question is: what's the currently accepted theory? I see nothing on accessible places like Wikipedia or physics stack exchange that there's even a question about this. The weak bosons get their rest mass via the Higgs mecanism, the fermions through the Yukawa coupling to the Higgs field. Until we discover a better answer.
And there must be a better answer one day, because we can't derive these rest masses from first principle
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To me that just means that the M-theory simply doesn't deserve its status as a physics theory if we have no experimental backup. It may qualify as a mathematical theory (which is probably where these ideas came from in the first place) but for physics it would be still a hypothesis.
Higgs Does Explain Fermion Masses (Score:3)
The higgs field explains the rest mass of the W and Z bosons through spontaneous symmetry breaking, however this mechanism can't explain the rest mass of fermions.
Yes, it absolutely does explain the fermion masses! In the Higgs mechanism, the fermions acquire masses by coupling to the Higgs field just like the W and Z bosons. Since the Higgs field has a non-zero vacuum expectation value from the spontaneous breaking and the field is scalar this coupling generates a mass term for each fermion.
The only possible exception are the neutrinos which could get their mass from the Higgs field but may also have other ways to gain mass and, some theorists think that their t
I thought everyone knew (Score:2)
Three is a magic number. [youtube.com]
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It is simple math, high low and in-between, left right and in-between, positive negative and in-between. So any oscillation will have the two extremes and the middle point of those two extremes, the logical simplest form and it will appear everywhere in everything at it's simplest form. The reason why it is not two is because there will always be the middle point, the neutral point between the two and thus three.
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Three is a magic number. [youtube.com]
0=1=1, 1=1
1+2=3, 3=3
1+2+3=6, 6=6
1+2+3+4=10, 1+0=1
1+2+3+4+5=15, 1+5=6
1+2+3+4+5+6=21, 2+1=3
1+2+3+4+5+6+7=28, 2+8=10, 1+0=1
1+2+3+4+5+6+7+8=36, 3+6=9
1+2+3+4+5+6+7+8+9=45, 4+5=9
1+2+3+4+5+6+7+8+9+10=55, 5+5=10, 1+0=1
1+2+3+4+5+6+7+8+9+10+11=66, 6+6=12, 1+2=3
1+2+3+4+5+6+7+8+9+10+11+12=78, 7+8=15, 1+5=6
1+2+3+4+5+6+7+8+9+10+11+12+13=91, 9+1=10, 1+0=1
1+2+3+4+5+6+7+8+9+10+11+12+13+14=105, 1+0+5=6
1+2+3+4+5+6+7+8+9+10+11+12+13+14+15=120, 1+2+0=3
1+2+3+4+5+6+7+8+9+10+11+12+13+14+15+16=136, 1+3+6=10, 1+0=1
1+2+3+4+5+6+7+8+9+
Re:I thought everyone knew (Score:4, Informative)
We've used other systems like base 12 before for practical reasons. There you can have halves, thirds, quarters, sixths, and twelfths of 12 all as integers. Pretty much the only field where this system has remained is in how we divide a day up into 12 hours, an hour up in 60 minutes and a minute up into 60 seconds. Metric time with the base 10 has been attempted, but failed.
The real problem with the logic is the use of the digit sum, because those digit sum additions resulting in so many 3s, 6s, and 9s only work out that well in the decimal system.
Take hexadecimal as an example where you'd have:
1+2+3+4+5+6 = 0xF = 0xF
1+2+3+4+5+6+7 = 0x15, 0x1+0x5 = 0x6
1+2+3+4+5+6+7+8 = 0x24, 0x2+0x4 = 0x6
1+2+3+4+5+6+7+8+9 = 0x2D, 0x2+0xD = F
1+2+3+4+5+6+7+8+9+10 = 0x37, 0x3+0x7 = A
1+2+3+4+5+6+7+8+9+10+11 = 0x42, 0x4+0x2 = 0x6
1+2+3+4+5+6+7+8+9+10+11+12 = 0x4E, 0x4+0xE = 0x12, 0x1+0x2 = 0x3
1+2+3+4+5+6+7+8+9+10+11+12+13 = 0x5B, 0x5+0xB = 0x10, 0x1+0x0= 0x1
Maybe lets take a look into the ternary system? That could be super magical, shouldn't it?
1+2 = 10t, 1t+0t = 1t
1+2+3 = 20t, 2t+0t = 2t
1+2+3+4 = 101t, 1t+0t+1t = 2t
1+2+3+4+5 = 120t, 1t+2t+0t = 10t, 1t+0t = 1t
1+2+3+4+5+6 = 210t, 2t+1t+0t = 10t, 1t+0t = 1t
And at this point if you think that the occurrence of 1t and 2t is somehow mystical know that in a number system were the only possibly numbers per digit are 0, 1, and 2, it can only be 1 or 2 for numbers greater than 0.
I don't think I need to continue at this point.
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Your post makes me wonder if you believe that the universe works on a decimal basis. And we don't know that.
No, I thought it was interesting and was curious what patterns other people had seen.
For all we know all number systems are equally valid. Apparently we just choose base 10 as our primary system because we have 10 fingers.
Probably, but why did we evolve to have 10 fingers? Was there something in the fabric of numbers that framed nature to evolve us with 10 digits and parrots to have 6? I don't know the answer to that however I see the patterns in numbers so I wonder if they are repeated.
We've used other systems like base 12 before for practical reasons. There you can have halves, thirds, quarters, sixths, and twelfths of 12 all as integers. Pretty much the only field where this system has remained is in how we divide a day up into 12 hours, an hour up in 60 minutes and a minute up into 60 seconds.
Perhaps check the part I wrote on Degrees/2 as there are 360 degrees in a circle *10=3600 seconds in an hour, 86400 seconds in a day.
3+6+0+0=9
8+6+4+0+0=18,
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The same applies to how we chose to represent a circle.
For what I know we chose it for *convenience, similar to why we chose the 12 hour day, or 3 barleycorns making up an inch and 12 inches in a foot. We chose it because of the amount of divisors where fractions of the base still result in integers. However there seems to be no inherent quality to nature that would suggest that this choice is somehow
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You're welcome. I already have done the math, the patterns are very interesting. When you look at them it's surprising but at the same time obvious.
Tertiary computations (Score:2)
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Our computers run in binary, what if the universe-computer runs in tertiary. That would explain it.
Abort, Retry, Fail?
Everyone knows.... (Score:4, Insightful)
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A cosmic triple? (Score:2)
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And there is a bar involved.
Re: A cosmic triple? (Score:2)
A photon, a gluon and a W boson walk into a bar. The bartender looks up and says âoeWhatâ(TM)ll it Z?â
Trinity signature (Score:4, Funny)
I'd sign my work, too.
What IS the pattern?? (Score:2, Insightful)
You say he mentions a pattern in the masses in his paper . . .
But you left out that ONE crucial detail that we all read this for!
What is it??
And, what is wrong with you?!
If that was for clickbait reasons, I hope you sit on a fire ant hill with an ass full of salted chili pickles!
Re: What IS the pattern?? (Score:2)
It turns out that it is vague, approximate, and doesnâ(TM)t always work. Other than that itâ(TM)s quite interesting.
Exotic cats? (Score:2)
"The second- and third-generation particles transform into their lighter counterparts too quickly to form exotic cats"
So, what are exotic cats made of then?
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Three-squared lives.
Because our universe is tri-dimentional (Score:3)
The smaller you get, the more each characteristic of matter seperates into its own particle: You have particles for charge, a particle for mass, etc.
What if, if you go small enough, the three dimensions of matter split into three fundamental particles, one for each dimension ?
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That would be a really satisfying explanation if space-time were not a thing. Really, the tight coupling of space and time is one of the most frustrating things about the universe. I'm given to understand that were it not so, FTL communication and travel might be a stronger possibility.
Ask Arthur C. Clark (Score:2)
Clark wrote about triple redundancy. Clearly, the universe needs backups.
Explains masses, not number of generations. (Score:4, Informative)
Being able to explain the masses of the generations would be an amazing breakthrough and extremely interesting but it still leaves of lot of things unexplained such as why are the neutrinos - even the third generation tau neutrino - so much lighter than the charged leptons and quarks. It also does not say why there are only three generations. The only hint we have of that so far is that three generations are the minimum number required for there to be a difference between matter and anti-matter (what we call CP violation): all other physics works fine with just one or two generations.
Three's occur in other places in the Standard Model too: we have three dimensions of space and the strong force, which binds quarks in atomic nuclei together, has three colour charges (and we have one dimension of time and one charge for electro-magnetism). But if these are in any way related to the three generations of quarks and leptons then so far we have no clue as to how.
Anyone able to explain this? (Score:2)
Anyone able to explain this to someone without a decent grasp of the subject? I tried to do some quick research into quark generations and it didn't help at all.
Re:Anyone able to explain this? (Score:4, Informative)
The short story is that particle colliders can create all kinds of bizarre particles besides the familiar protons, neutrons, and electrons, and further investigation into what those particles can be broken down into and built up out of gives six kinds of quarks, three kinds of lepton, and three kinds of neutrino, and the properties of those particles line up into three neat families or "generations": up and down quarks (that make up protons and neutrons in different combinations), electrons (the normal kind of lepton), and the electron-neutrino are the usual, first, generation, but there's also a heavier version of each of those that otherwise behaves the same (charm and strange quarks are like up and down quarks but heavier, muons are like electrons but heavier, and muon-neutrinos are like electron-neutrinos but heavier), and then even heavier versions of each of those (top and bottom quarks, tau leptons, and tau-neutrinos). But all of those heavier particles are so unstable that they quickly decay down to an assortment of first-generation particles (and photons) before they could form any more complex structures.
Gaudy epicycle-encrusted model just isn't right (Score:2)
Nah. Too many epicycles for my taste. But good may come out of this if it inspires other theoreticians to think along new lines, perchance to come up with a slick new idea that reduces the hodge-podge made-up mess of the Standard Model to something simpler, more elegant.
Re: Gaudy epicycle-encrusted model just isn't righ (Score:2)
Lucky Pierre agrees (Score:2)
Third Time's a Charm Quark (Score:2)
Clearly it took the Universe three times to get the particles right due to the Murphy Field, the existence of which is proven by the fact that it always takes at least three times to get something right, including grand theories.
Consequence of intelligent design (Score:1)
Consequence of intelligent math. (Score:2)
One jokes, but the Trinity like all great artists signs it's work.
Sounds like Brian Whitworth's theory? (Score:2)
Brian Whitworth's theory on quantum realism begins with a simple theoretical quantum reality framework, and derives many features inherent in the standard model, like why matter comes in three families, as well as why the electron has spin 1/2 (and what spin is), where the "strong force" comes from and if gluons are real (no). The theory deduces the order of electrons filling shells in atoms, and the equivalence of gravity and acceleration, and suggests a mechanism for dark matter and dark energy. All that
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Brian Whitworth's theory on quantum realism...
Read quite a lot of it. It was one long tortured analogy asserting a model of reality based on a severely limited imagination. Not much worse than the crap the string theorists spout, but equally useless.
That's not to say that modern physics isn't stuck in a rut—it is. Stephen Hawking himself said so, and he was far from the only physicist who thought so, nevermind the rest of us. The inability to decide exactly how descriptive of reality quantum electrodynamics actually is does seem to be the sti
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Stephen Hawking was light on mathematical rigor in A Brief History of Time. It had just one equation.
Because it's funny (Score:3)
Since the first cave-comedian cracked the first joke ("Fire bad! Am I right?"), it's been common knowledge that three is inherently funny. You tell the first part of the joke to establish what the audience should expect; you tell the second part of the joke to establish that there is a pattern; you tell the third part of the joke to get the audience into a mindset expecting the pattern to continue - then BAM! you fool them with an unexpected twist in the punchline.
Physicists are just comedians in lab coats.