Introductory remarks

1982 ◽  
Vol 304 (1482) ◽  
pp. 3-4
Keyword(s):  
World War Ii ◽  
Magnetic Moment ◽  
Anomalous Magnetic Moment ◽  
Quantum Electrodynamics ◽  
Power Series Expansion ◽  
Structure Constant ◽  
Fine Structure Constant ◽  
Quantum Field Theories ◽  
Quantum Field ◽  
Abelian Gauge

The title of this meeting, which refers to gauge theories, could equivalently have specified renormalizable quantum field theories. The first quantum field theory arose from the quantization by Dirac, Heisenberg and Pauli of Maxwell’s classical theory of electromagnetism. This immediately revealed the basic problem that although the smallness of the fine-structure constant appeared to give an excellent basis for a power-series expansion, corrections to lowest order calculations gave meaningless infinite results. Quantum electrodynamics (QED ) is, of course, an Abelian gauge theory, and the first major triumph o f fundamental physics after World War II was the removal of the infinities from the theory by the technique of renormalization developed by Schwinger, Feynman and Dyson, stimulated by the measurement of the Lamb shift and the anomalous magnetic moment of the electron. In the intervening years, especially through the beautiful experiments at Cern on the anomalous magnetic moment of the muon, the agreement between this theory and experiment has been pushed to the extreme technical limits of both measurement and calculation.

scholarly journals Theory of the Anomalous Magnetic Moment of the Electron

Atoms ◽  
2019 ◽  
Vol 7 (1) ◽  
pp. 28 ◽  
Author(s):  
Tatsumi Aoyama ◽  
Toichiro Kinoshita ◽  
Makiko Nio
Keyword(s):  
Fine Structure ◽  
Magnetic Moment ◽  
Anomalous Magnetic Moment ◽  
Quantum Electrodynamics ◽  
Penning Trap ◽  
Weak Interactions ◽  
Perturbation Expansion ◽  
Structure Constant ◽  
Fine Structure Constant ◽  
Best Value

The anomalous magnetic moment of the electron a e measured in a Penning trap occupies a unique position among high precision measurements of physical constants in the sense that it can be compared directly with the theoretical calculation based on the renormalized quantum electrodynamics (QED) to high orders of perturbation expansion in the fine structure constant α , with an effective parameter α / π . Both numerical and analytic evaluations of a e up to ( α / π ) 4 are firmly established. The coefficient of ( α / π ) 5 has been obtained recently by an extensive numerical integration. The contributions of hadronic and weak interactions have also been estimated. The sum of all these terms leads to a e ( theory ) = 1 159 652 181.606 ( 11 ) ( 12 ) ( 229 ) × 10 − 12 , where the first two uncertainties are from the tenth-order QED term and the hadronic term, respectively. The third and largest uncertainty comes from the current best value of the fine-structure constant derived from the cesium recoil measurement: α − 1 ( Cs ) = 137.035 999 046 ( 27 ) . The discrepancy between a e ( theory ) and a e ( ( experiment ) ) is 2.4 σ . Assuming that the standard model is valid so that a e (theory) = a e (experiment) holds, we obtain α − 1 ( a e ) = 137.035 999 1496 ( 13 ) ( 14 ) ( 330 ) , which is nearly as accurate as α − 1 ( Cs ) . The uncertainties are from the tenth-order QED term, hadronic term, and the best measurement of a e , in this order.

Quantum electrodynamics between conducting plates III. Relativistic theory and magnetic moment of the free electron

1972 ◽  
Vol 326 (1565) ◽  
pp. 277-288 ◽  
Keyword(s):  
Magnetic Moment ◽  
Free Electron ◽  
Quantum Electrodynamics ◽  
Structure Constant ◽  
Preceding Paper ◽  
Fine Structure Constant ◽  
Parallel Plates ◽  
Order Of Magnitude ◽  
Plate Separation ◽  
Theory Calculation

We calculate the change δμ in the radiative correction to the magnetic moment μ of a free electron, when the electron is inserted between infinite perfectly conducting parallel plates. The order of magnitude is given by δμ/μ ∼ αA/ L , with a the fine structure constant, A the Compton wavelength, and L the plate separation. This contrasts with a bound electron, for which the preceding paper found δμ/μ ≈ α( A / L 2 ). Since a relativistic field theory calculation is essential for δμ, we obtain as a by-product a relativistic confirmation of the leading spinindependent energy shifts for a free electron, reported in an earlier paper.

A Parenthesis on “R2QFTs” ⋆⋆

2018 ◽  
pp. 70-75
Author(s):  
Alvaro De Rújula
Keyword(s):  
Standard Model ◽  
Magnetic Moment ◽  
Anomalous Magnetic Moment ◽  
Relativistic Quantum ◽  
Field Theories ◽  
Quantum Field Theories ◽  
Quantum Field ◽  
Quantum Fields ◽  
The Standard Model

Renormalizable Relativistic Quantum Field Theories (R2QFTs) are theories In which a few parameters must be taken from observations but otherwise make predictions on the phenomena they describe. The ingreedients of the Standard Model of particles are examples. The most precise of them is Quantum Electro-Dynamics (QED). The QED prediction of the “anomalous” magnetic moment of the muon is discussed as a detailed example. Relativistic quantum fields describe all aspects and properties of particles and their interactions, they are “the mother of all concepts.”

scholarly journals An Investigation Into The Mathematical and Physical Origins of The Fine-Structure Constant

2021 ◽  
Author(s):  
Lamont Williams
Keyword(s):  
Fine Structure ◽  
Magnetic Moment ◽  
Anomalous Magnetic Moment ◽  
Quantum Physics ◽  
Ad Hoc ◽  
Structure Constant ◽  
Fine Structure Constant ◽  
Quantum Mechanical ◽  
The Standard Model ◽  
Corrective Term

Abstract The fine-structure constant, α, unites fundamental aspects of electromagnetism, quantum physics, and relativity. As such, it is one of the most important constants in nature. However, why it has the value of approximately 1/137 has been a mystery since it was first identified more than 100 years ago. To date, it is an ad hoc feature of the Standard Model, as it does not appear to be derivable within that body of work — being determined solely by experimentation. This report presents a mathematical formula for α that results in an exact match with the currently accepted value of the constant. The formula requires that a simple corrective term be applied to the value of one of the factors in the suggested equation. Notably, this corrective term, at approximately 0.023, is similar in value to the electron anomalous magnetic moment value, at approximately 0.0023, which is the corrective term that needs to be applied to the g-factor in the equation for the electron spin magnetic moment. In addition, it is shown that the corrective term for the proposed equation for α can be derived from the anomalous magnetic moment values of the electron, muon, and tau particle — values that have been well established through theory and/or experimentation. This supports the notion that the corrective term for the α formula is also a real and natural quantity. The quantum mechanical origins of the lepton anomalous magnetic moment values suggest that there might be a quantum mechanical origin to the corrective term for α as well. This possibility, as well as a broader physical interpretation of the value of α, is explored.

scholarly journals The Anomalous Magnetic Moment of the Electron and Proton Cores According to the Planck Vacuum Theory

2019 ◽  
Vol 4 (6) ◽  
pp. 117-119
Author(s):  
William C. Daywitt
Keyword(s):  
Fine Structure ◽  
Dirac Equation ◽  
Quantum Electrodynamic ◽  
Magnetic Moment ◽  
Anomalous Magnetic Moment ◽  
Structure Constant ◽  
Fine Structure Constant ◽  
The Relationship ◽  
Vacuum Theory ◽  
The Invisible

Despite the resounding success of the quantum electrodynamic (QED) calculations, there remains some confusion concerning the Dirac equation’s part in the calculation of the anomalous magnetic moment of the electron and proton. The confusion resides in the nature of the Dirac equation, the fine structure constant, and the relationship between the two. This paper argues that the Dirac equation describes the coupling of the electron or proton cores to the invisible Planck vacuum (PV) state (involving e2 ); and that the fine structure constant ( = e2/e2 ) connects that equation to the electron or proton particles measured in the laboratory (involving e2).

scholarly journals No Eigenvalue in Finite Quantum Electrodynamics

1997 ◽  
Vol 12 (21) ◽  
pp. 3799-3809
Author(s):  
R. Acharya ◽  
P. Narayana Swamy
Keyword(s):  
Field Theory ◽  
Quantum Field Theory ◽  
Fine Structure ◽  
Quantum Electrodynamics ◽  
Structure Constant ◽  
Fine Structure Constant ◽  
Quantum Field

We re-examine Quantum Electrodynamics (QED) with massless electron as a finite quantum field theory as advocated by Gell-Mann–Low, Baker–Johnson, Adler, Jackiw and others. We analyze the Dyson–Schwinger equation satisfied by the massless electron in finite QED and conclude that the theory admits no nontrivial eigenvalue for the fine structure constant.

scholarly journals Enhanced Derivation of the Electron Magnetic Moment Anomaly from the Electron Charge using Geometric Principles

2018 ◽  
Vol 10 (6) ◽  
pp. 24 ◽  
Author(s):  
Andrew Worsley ◽  
J.F. Peters
Keyword(s):  
Fine Structure ◽  
Standard Model ◽  
Magnetic Moment ◽  
Geometric Model ◽  
Structure Constant ◽  
Fine Structure Constant ◽  
Electron Charge ◽  
Mathematical Equation ◽  
The Standard Model ◽  
Electron Magnetic Moment

The electron magnetic moment anomaly is conventionally derived from the fine structure constant using a complex formula requiring over 13,000 evaluations. However, the charge of the electron is an important parameter of the Standard Model and could provide an enhanced basis for the derivation of the electron magnetic moment anomaly. This paper uses a geometric model to reformulate the equation for the electron’s charge, this is then used to determine a more accurate value for the electron magnetic moment anomaly from first geometric principles. This enhanced derivation uses a single evaluation, using a concise mathematical equation based on the natural log e^pi. This geometric model will lead to further work to theoretically improve the understanding of the electron.

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