That's easy to say when your only calculation gets everything wrong except the order of magnitude.
To be honest, you don't seem to know much about either.
Nuclear Strong Force is a Fiction
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That's easy to say when your only calculation gets everything wrong except the order of magnitude.
To be honest, you don't seem to know much about either.
Hellbound
Merchant of Doom
Funny, also, that this argument never worked in any of my science classes in college.
ETA: Although it did lead to some interesting results in Chemistry lab...*twitch*
Putting their names in quotation marks doesn't make them any more imaginary.
bjschaeffer
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You too.
Reality Check
Penultimate Amazing
Wow - lots of science there bjschaeffer!
It is easy to see that your knowledge of nuclear physics is limited.
For example: Nucleons do not form dipoles with +/1e charges because they are made up of quarks: Evidence for the Strong Force (PDF). Quarks have fractional charges.
ben m happens to be a nuclear physicist!
In 1990, you would have said the same thing about mesons. "QCD is missing the target and will never be able to calculate the mass of a single pion", you would have said, using the same logic (or non-logic) you have now. Unfortunately, as computing power (and QCD algorithms) improved, we brute-forced our way through and solved that problem---lattice QCD has finally succeeded in predicting light meson masses.
Why, exactly, do you think "some things are too hard to calculate" means "the theory is garbage"? You have not even tried to explain this, you just state it as though it was a fact.
If QCD is so "fantastical", why does it work so well at high energies? I would welcome from you a list of experiments that disagree with QCD's many predictions. That's basically a rhetorical question: I know you will not provide such a list, because there isn't one, which I know because I've been studying this stuff for 15+ years.
If the weak force is so fantastical, why does it work so well everywhere? I would welcome from you a list of experiments that disagree with electroweak theory. I know you will not provide such a list, because there isn't one, which I know because I've been studying this stuff for 15+ years. If you had a serious complaint about the weak interaction, you'd be pointing to the NOMAD Weinberg angle anomaly, or the MiniBOONE low-energy neutrino data, or the muon g-2 anomaly, or one of the things that serious weak-interaction physicists---who, in general, would be thrilled to find an experimental deviation from the Standard Model weak interaction---use to motivate the hope for such deviations.
ETA: NOMAD, MiniBOONE, and muon g-2 disagree with the best available Standard Model calculations by 2.5--3.5 sigma. My view of these, which is not atypical, is: NOMAD's deviation is consistent with an ordinary statistical fluctuation; MiniBOONE's disagreement is dominated by a difficult-to-calculate background which they may have simply gotten wrong; g-2's "theory" is a very difficult calculation, incorporating 8-loop QED, 2-loop weak interactions, and QCD, with an unfortunate history of negative-sign errors. Of the three, in my opinion g-2 seems the most likely to be a real effect with hints of non-Standard-Model physics, followed by MiniBOONE (which, if it's a real effect, has candidate explanations in sterile neutrinos), followed by NOMAD (haven't seen an idea I like).
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bjschaeffer
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You say always many things you read but no proof. I only need an understandable calculation with fundamental constants and laws.
All fundamental laws are simple. It becomes complicated only for complicated objects.
Dancing David
Penultimate Amazing
Yeah and your precision is an order of magnitude?
Gell-Mann nailed it much closer as did Yukawa.
But I do see on the other hand that your rhetorical skills are strong.
So if Gell-Mann could come within a fraction, why do you need an order of magnitude?
http://www.bnl.gov/bnlweb/history/Omega-minus.asp
Hmmm?
Since you're new to this, I recommend starting with a basic, undergrad-level textbook. May I suggest Griffiths "Introduction to Elementary Particles" for basic concepts, followed by Perkins "Introduction to High Energy Physics" for more detail, including some understandable basic hadron physics and experimental details. If you understand that you need graduate-level QFT (try Srednicki, or Peskin & Schroder) which is the appropriate introduction to "Quantum Chromodynamics" by Greiner et. al.
Short of that, I fear, anything I post will be labeled "not proof".
ETA: in other words, everything I'm talking about is well known. It's been developed under the eyes of thousands of people, taught to people who taught it to people who teach it now; it's been reviewed (approvingly) by thousands of reviewers at journals, at funding agencies, and on hiring committes. It's been awarded a Nobel prize. If you wanted to look up any fact in the post you quoted, you could find a dozen reliable sources on it. It's fine to want "proof," but if you actually wanted it you'd go look for it---you wouldn't be demanding that I type it out myself.
Your theory, on the other hand, is something you made up. There is no source on it other than you. The burden is on you to prove your theory.
How do you know?
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bjschaeffer
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I believe only what is proved not on legends , even well known. You just repeat what is in the books without understanding it.
Each new theory has no source and is generally simple at its origin, Newton, Coulomb, Einsten, de Broglie have discovered simple formulas.
I don't know who you are.
What makes you think I don't understand it? It's true that I disagree with you, but that only means one of us doesn't understand something.
How hard have you tried to understand?
More practically: can you narrow down your objection? Rather than saying "Everything is wrong", can you crack open any particle physics textbook (I have Griffiths, Perkins, Das & Ferbel, Peskin, Halzen & Martin, Walecka, and Barger & Philips handy), point to a specific detail of anything, and tell me why you think it's wrong?
I'm "ben_m", a substantially-anonymous poster on the JREF forum where you chose to present your theory. I'm some guy who wrote a forum post you disagree with, and you said so. You're some guy who wrote a paper I disagree with, and I said so.
If you want to ignore me, I can't stop you. That doesn't make my post criticizing your theory disappear, so you must hope that the average reader (who, likewise, doesn't know either of us) will read my post, and your responses so far, and choose to agree with you rather than me. That's more or less how science arguments work.
dafydd
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I'm sticking with real physicists instead of the pretend one.
jsfisher
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bjschaeffer
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How hard have you tried to explain?
Explain what? QCD? That takes a textbook. Lattice calculations, chiral effective theory? Textbook. If you had a more specific question it would help.
Well, I'll feed you a question. Why does QCD, which has a simple Lagrangian, not yield simple solutions? This is easy: When you want to do a quantum-mechanical calculation, say in a scattering cross section, you take the experimental details (what particles start where) and you need to find what happens. The underlying theory is a Lagrangian, which you need to evaluate in the form of a quantum-mechanical path integral. That means, you need to write down the action along all possible paths through space, turn each such path's action into an amplitude, and add them up.
This sounds impossible, right? There are infinity possible paths, right? Not quite. In a weakly-coupled theory, like QED or the weak interaction, you can use analytic methods to throw away most of the paths; the simple paths behave like the first terms of a series expansion, and increasingly complex paths are suppressed. This is called perturbation theory. Do you know about this? In QED and weak interactions, we have this mathematical stroke of luck---the infinite list of paths can be evaluated, accurately, with a very short list of calculations.
QCD works just the same way. There's a simple Lagrangian. You plug in experimental details (particle x coming from the left at speed v, etc.) and start working out the path integral to find out what happens. In terms of the underlying physics, it's just the same thing you do for QED and weak interactions---except that the perturbative "trick" doesn't work. The coupling constant is too strong, so the arbitrarily-long list of paths does *not* simplify, and the only way to compute the path integral is to brute-force it. ("Lattice QCD" can make the integral *finite*, but it's still very, very *long*.)
Maybe the right question is NOT "why is QCD so hard?". The right question is "why does QED simplify so much?" And the answer is NOT "all theories are simple"---QED is not inherently simple. It gets simplified, and computable, and vaguely-1/r^2-like, thanks to the spectacular, tour-de-force math wizardry that destroys an inherently complicated path integral.
Well, I'll feed you a question. Why does QCD, which has a simple Lagrangian, not yield simple solutions? This is easy: When you want to do a quantum-mechanical calculation, say in a scattering cross section, you take the experimental details (what particles start where) and you need to find what happens. The underlying theory is a Lagrangian, which you need to evaluate in the form of a quantum-mechanical path integral. That means, you need to write down the action along all possible paths through space, turn each such path's action into an amplitude, and add them up.
This sounds impossible, right? There are infinity possible paths, right? Not quite. In a weakly-coupled theory, like QED or the weak interaction, you can use analytic methods to throw away most of the paths; the simple paths behave like the first terms of a series expansion, and increasingly complex paths are suppressed. This is called perturbation theory. Do you know about this? In QED and weak interactions, we have this mathematical stroke of luck---the infinite list of paths can be evaluated, accurately, with a very short list of calculations.
QCD works just the same way. There's a simple Lagrangian. You plug in experimental details (particle x coming from the left at speed v, etc.) and start working out the path integral to find out what happens. In terms of the underlying physics, it's just the same thing you do for QED and weak interactions---except that the perturbative "trick" doesn't work. The coupling constant is too strong, so the arbitrarily-long list of paths does *not* simplify, and the only way to compute the path integral is to brute-force it. ("Lattice QCD" can make the integral *finite*, but it's still very, very *long*.)
Maybe the right question is NOT "why is QCD so hard?". The right question is "why does QED simplify so much?" And the answer is NOT "all theories are simple"---QED is not inherently simple. It gets simplified, and computable, and vaguely-1/r^2-like, thanks to the spectacular, tour-de-force math wizardry that destroys an inherently complicated path integral.
Your turn.
In your model, you say that the charge-arrangement in a proton/neutron system looks like this: (I denote charges by + and -, and magnetic dipoles by "u").
Where you claim to have minimized r2, and you claim that r3 is something large you don't care to calculate. But you're wrong. The following has a higher binding energy and is a better ground state. You don't explain why the "magnetic moment" remains exactly at r2; why can't it be elsewhere within the neutron?
The following has a much, much higher binding energy, because of the potential energy within the neutron which you ignored:
And, in fact, that's the true ground state of your model. Your model, if you had done the E&M correctly (varying r2 and r3 together to minimize energy, rather than ignoring r3) predicts that the neutron and the proton are simply repelled from one another by the magnetic moments. (Or attracted, if the polarities are opposite.)
Explain. I even supplied the question.
In your model, you say that the charge-arrangement in a proton/neutron system looks like this: (I denote charges by + and -, and magnetic dipoles by "u").
Code:
proton <----neutron------->
(+/u)----- r2 ---(-/u)------r3------(+)
Code:
proton <----neutron---->
(+/u)--r2--(-)-------(u)-(+)The following has a much, much higher binding energy, because of the potential energy within the neutron which you ignored:
Code:
proton <neutron>
(+/u)-------------(-)(u)(+)And, in fact, that's the true ground state of your model. Your model, if you had done the E&M correctly (varying r2 and r3 together to minimize energy, rather than ignoring r3) predicts that the neutron and the proton are simply repelled from one another by the magnetic moments. (Or attracted, if the polarities are opposite.)
Explain. I even supplied the question.
bjschaeffer
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I don't understand your question you just need to apply the electric in 1/r (not 1/r2) and magnetic in 1/r3 Coulomb potentials for the approximate calculation of the deuteron. This gives an analytical solution. If you want a better precision, you draw the curve with the dipole and take the minimum graphically. You have the formulas and the graph on post #525. You need only the fundamental constants, here
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Dancing David
Penultimate Amazing
Whoosh.
Let me re-re-reexplain. I'll stick to the easy part.
There are three charges in your setup. Right? The proton charge (p+), your half-neutron (n-), and your half-neutron (n+). In doing your calculation, you took into account the electrostatic potential between p+ and n-. You call that distance r_{np}, so you plugged in binding energy -1/r_{np}.
You *ignored* the separation (d) between n- and n+ inside the "neutron". But that's is indeed a charge-separation, and incurs a binding energy -1/d. You thought you could ignore this term and call it an "approximation", but the term you ignored is much, much more important than the term you included.
(You also ignored the repulsive p+ n+ potential, at distance (d+r_{np}). At least you *knew* you were ignoring this one, and since you guessed that d was large it was reasonable to ignore it. But d isn't large, as we will see.)
Go ahead, BJschaeffer, try this: calculate the potential energy of a state with r_np = 1 fm and d=1. That's pretty close to the thing *you* think is the bound state. (Include the magnetic repulsion or not, I don't care, it doesn't help.) Tell me the total energy.
Try this: calculate the potential energy of a state with r_np = 1 and d=0.01---a case where the neutron *does not* "polarize", but stays compact . Tell me the total energy. It's lower. How is it that you "minimized the energy" but I can find a lower-energy state? Because your approximation was missing an important term, and mine is not.
In fact, the binding energy is arbitrarily large for d=0. What does this tell us? Well, it tells *me* the same thing that it told Niels Bohr: charge bound states are constrained by quantum mechanics, so your whole electrostatic model, which ignores quantum mechanics, is gibberish. What should it tell *you*? It should tell you that your electrostatic model was a "nice try", and now that you've worked it out better, you see that it does NOT have a deuteron-like bound state.
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