How do you understand the inconsistency between theoretical and experimental values of muon anomalous magnetic moment?Does that mean QED is wrong? shareing your opinion.
The agreement for the corresponding electron anomaly, measured to order-of-magnitude better accuracy, rules out possible problems with QED itself. But, since the muon is 200 times heavier than the electron, the muon anomaly is more sensitive to contributions from (virtual) heavy particles not described by the Standard Model. So that is the most natural explanation for the discrepancy, next to simply being a statistical fluke (the current deviation is too small to classify as "a discovery").
The experimental accuracy is expected to improve by a factor 4 with the now running E989 experiment at Fermilab,
https://scipost.org/preprints/scipost_201811_00011v1/
The putative ``inconsistency'' is, in fact, nothing but due to the uncertainties in computing ``light-by-light scattering'' due to the hadronic contributions of known particles, that require an involved calculation, since they are ``long distance effects''.
Cf. here: https://indico.in2p3.fr/event/18268/contributions/68432/attachments/51923/66915/talk.pdf
As I read the presentation by Lellouch, the light-by-light hadronic theoretical uncertainty is one possible explanation, yet to be confirmed. Apparently the current estimate must be off by a factor of about 2 to make up the deficit.
There is another set of papers which say (at least used to say) that the discrepancy may be due to gravitational curvature(!) influencing the muon precession in the experimental ring, https://arxiv.org/pdf/1801.10244.pdf. I guess this would not influence measurement of the electron anomaly in the same way, due to a different geometry. It would be fantastic if one were able to observe gravitational curvature in this way (one more way to test GR), but it sounds too good to be true. If it is true, I think a measurement of the electron precession must be much better.
The good thing is that there still are some exciting questions left in particle physics!
Hi,Ph.D Kåre Olaussen,Thank you for your participation in the discussion.
The paper you add present the latest research about the muon anomaly ,that very very practical!😊
The paper about a gravitational contribution, alas, can't be correct. The reason isn't just, quantitative, but qualitative, since the metric isn't a physical field and the measurement is local. For more details, cf. http://realselfenergy.blogspot.com/2018/02/update-on-muon-g-2-story-of-debacle.html
If the hadronic light-by-light contribution isn't under control, there just can't be any meaningful statement about a discrepancy at all. And the point is that, as the lattice studies (that are the only ones that can provide a well-defined answer) become more and more precise, any discrepancy with experimental measurements is no longer statistically significant.
Stam> The paper about a gravitational contribution, alas, can't be correct.
Yes, you are absolutely right! I only looked superficially at the paper, and thought they computed an entirely different effect (as my post indicates; I was a bit puzzled that it could be so large).
What should have stopped the authors (and the editor/referees of Prog. Theor. Exp. Phys.), even if they only had a vague understanding of the topic, is that this provides an explanation which must work universally. And therefore simultaneously destroys the existing, much better, agreement between theory and experiment for the electron anomaly. Cherry-picking explanations and formulas for one particular observation, without checking against all other relevant observations, is not science.
The curvature effect I had in mind is physical one: Barring cancellations due to symmetry, there may be some extra precession due to the tiny deviation from euclidean geometry at the surface of the earth. This is characterised by a curvature of magnitude 10-23 m-2. Applied to the muon ring of area 160 m2, this indicates an effect of relative order 10-21, ridiculously small.
On the issue of the inconsistent, some friends considered experimental value is wrong, then redid the experiment; Some friends think it is the limitation of human exploration, the existence of unknown particles influence; Some friends think it is the effect of gravitational contribution...
In a word, it's clear that nobody thinks QED is wrong whether the past or the present. But I'm going to stab everybody in the chest, because my point is that QED's interpretation of the anomalous magnetic moment of the electron family is logically wrong!
in short, QED used external reason (electromagnetic field) to explain Intrinsic attribute exception (the anomalous magnetic moment) of electrons is unreasonable, if γ- e collision determines the anomalous magnetic moment of electrons, that means it is established for all the charged particles, ,but why the reason of the anomalous magnetic moment of proton is the strong nuclear force?
The intrinsic property is determined by internal factors. In the stage of elementary particles, particles are defined by physical properties. Logically speaking, the particles coming firstly than interactions between particles. On the contrary, defining the intrinsic properties of particles by the interaction between particles to is walking backward!
I list two examples about the intrinsic property is determined by internal factors. :
1. The main reason of the anomalous magnetic moment of proton is strong interaction.the probability of the transformation between u and d quarks, or releasing (or absorbing) a negative pion is 1/2, so the anomalous factor =2Mp/(Mp+Mn+Mπ) can be quantitatively calculated;
2. The reason why neutron magnetic moment is not zero, is also due to the strong interaction,In fact, the neutron-magnetic moment = proton-magnetic moment + negative pion-magnetic moment . the anomalous magnetic moment of Proton or neutron produced by the same reason, but the impact of different ways.
The electrons is the point particles ,that is different from nucleons who have internal structure. Therefore, from the particle itself, the dynamic process which could cause its intrinsic properties to change is decay! Since all the decay models of the electrons are weak decay!It means that the weak nuclear force causes the anomaly of electrons magnetic moment!
Let me talk about how to calculate three kinds of electrons-anomaly magnetic moment:
I. potential energy and energy changed by electrons gaining (or losing) a neutrino and forming a special positronium;
II. Interference between the three kings of positroniums ;
III. Electronic origin (n→p+e+ve influence).
If you are interested in it, you can read my paper "Cause Analysis of Magnetic Moment Anomaly of Electron Family -- Divergence between Electromagnetic Force and Weak Nuclear Force".
I know it’s hard to spread my new ideas, but I still believe Facts are stronger than arguments! The error of using external reason to explain intrinsic property of particles must be addressed!be rectified ! My battle has just begun! I will fight for the truth all my life!
Zhengdong Huang > The main reason of the anomalous magnetic moment of proton is strong interaction.
The main explanation for the magnetic moments of the proton and neutron is that they emerge from the three spin-1/2 quarks of different charges. A good introduction is f.i. the book Introduction to Elementary Particles, by David Griffiths, https://www.adlibris.com/no/bok/introduction-to-elementary-particles-9783527406012. If you are interested in these issues in a serious way, you must first study the basic knowledge presented in this book, or some equivalent source of information.
Zhengdong> It means that the weak nuclear force causes the anomaly of electrons magnetic moment!
I cannot follow your reasoning at all; it certainly is not based on any existing experimental evidence from particle physics, the theories describing and explaining this evidence, or even the general scientific principles which theory building must obey.
But anyway, let me briefly take your statement as a working hypothesis. You want to base your explanation on properties of the weak nuclear force. Then, which value do you use for the Weinberg angle, the masses of the W and Z bosons? Shouldn't you be worried that the experimental values of these quantities, very basic for any description of the weak nuclear forces, are only known to much less accuracy that the electron anomaly? How come that none of these quantities are used in your tables?
Oh, you don't know what I am talking about? Well, if you are interested in these issues in a serious way, you must first study the basic knowledge presented in the book I mentioned above, or some equivalent source of information.
Zhengdong> My battle has just begun! I will fight for the truth all my life!
In general, I have considerable sympathy for such attitude. But you must be careful to distinguish between true facts and fictitious dreams, and which battles you chose to fight. There is a famous story about Don Quijote, and his "heroic" fight against windmills.
Dear Sir Kåre Olaussen,Thank you for your repy，I think there are some problems that are not clear！
1.The arguement is "QED uses other particles(like γ) to explain intrinsic properties of the eletrons",right or not right?Could you give me your answer?
2.I think it is wrong ，because "the intrisic property is determined by internal factors".So,from particles-self,"DECAY" is the only possible!
3.On the proof of the decay method.I used the "weak nuclear force potential energy formula" to calculate the effect of decay on the mass,not"SCATTERING"or"W±"、"Z0".If you are still in ,I'm still in forever!
4.I'm introducing p/n just to prove"THE INTRISIC PROPERTY IS DETERMINED BY INTERNAL FACTORS".Your quote also proved the point.In addtion ,I had published the formula before,If you have any questions, please clarify！(I had read the book in chinese)
Zhengdong Huang > I had read the book in chinese
Good; I hope you still have access to it. I advice you to make a serious study of it, if you are interested in elementary particle physics (of course, it only provides a necessary introduction).
Zhengdong> QED uses other particles (like γ) to explain intrinsic properties of the electrons", right or not right?
It depends on what you mean by "particles". The fact that many elementary particles have electric charge is an intrinsic property, and that fact inevitably imply many other computable intrinsic properties of such particles. You must not confuse the procedure of mathematically constructing real particles by a quantum superpositions of some idealised "bare" particles (f.i. bare electrons, positrons and photons) with stringent philosophical views about nature. The former is just a mental process which can simplify calculations and intuition.
Zhengdong> If you have any questions, please clarify
I asked a couple of questions in my previous post, which you did not respond to.
Kåre Olaussen>I'm glad you could think about my question,and I'm sorry for wasting your time.
"Introduction to Elementary Particles" is a good book .I have studied for a long time,and gained a lot.
If you don't know how to distinguish particles,I suggest you inquire about PDG particle list (http://pdg.lbl.gov/2018/mobile/),but not Philosophy！
If I find a problem and don't speak up, it's my remiss;If I do,but no one response, for all I care.
Now，I have shown people what the problem is,and people start to think about it,My goal is achieved.So I don't care your answer is or isn't satisfactory!
The coming days would be long!After redid muon ,tauon coming!
You still did not answer my questions. That is OK with me. But please don't be disappointed when physicists reject your work. Your writings make me concerned about your health; take care.
NO!NO!NO!I feel good in my heart and body,I like exercise,I'm keeping fit through running,swimming,playing badminton,riding a bike💪，I also like bonsai🌴.When I'm running in the woods in the early morning, I feel my brain is full of spirituality👫! en...I don't know what the questions you want me to answer,you had not read my paper by now😏😏😏.
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