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Revised value of the eighth-order contribution to the electron g-2
T Aoyama1, M Hayakawa, T Kinoshita
1Theoretical Physics Laboratory, Nishina Center, RIKEN, Wako, Saitama 351-0198, Japan.
Physical Review Letters
|October 13, 2007
Summary
A recalculation of the electron
Area of Science:
- Quantum Electrodynamics (QED)
- Particle Physics
Background:
- The anomalous magnetic moment (g-2) of the electron is a fundamental quantity in QED.
- Precise theoretical calculations are crucial for testing the Standard Model.
Purpose of the Study:
- To recalculate the eighth-order contribution to the electron's anomalous magnetic moment.
- To identify and correct inconsistencies in previous theoretical calculations.
Main Methods:
- Utilized a new FORTRAN code generated by an automatic code generator for recalculations.
- Focused on diagrams contributing to the eighth-order (g-2) without closed lepton loops.
- Compared individual diagram contributions between old and new calculations.
Main Results:
- Identified an inconsistency in the old treatment of Infrared (IR) subtraction terms in two diagrams.
- Revised the eighth-order contribution to -1.9144(35)(alpha/pi)4.
- Determined a shift in the inverse of the fine structure constant of -6.411 80(73)x10(-7).
Conclusions:
- The corrected theoretical value refines our understanding of electron's anomalous magnetic moment.
- This revision has implications for the precise determination of the fine structure constant.
- Highlights the importance of accurate computational methods and error checking in theoretical physics.
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