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Pairwise Multiparticle States and the Monopole Unitarity Puzzle.
Csaba Csáki1, Yuri Shirman2, Ofri Telem3,4
1Department of Physics, LEPP, Cornell University, Ithaca, New York 14853, USA.
Physical Review Letters
|November 14, 2022
Summary
Researchers resolved a long-standing physics puzzle regarding positron scattering off monopoles. The study identifies a novel two-up, one-down quark entangled state as the unique solution satisfying conservation laws.
Area of Science:
- Particle Physics
- Theoretical Physics
- Grand Unification Theories
Background:
- A decades-old mystery in particle physics involves positron scattering off grand unification theory monopoles.
- This puzzle, initially proposed by Callan in 1983, has lacked a definitive resolution.
Purpose of the Study:
- To propose a novel resolution to the positron-monopole scattering puzzle.
- To identify the specific particle final state consistent with fundamental conservation laws.
Main Methods:
- Utilized the framework of on-shell amplitudes.
- Employed the concept of pairwise helicity to analyze the scattering process.
- Investigated solutions in dimensions greater than two.
Main Results:
- Identified a unique final state consisting of two up quarks and one down quark.
- This state is an entangled multiparticle configuration satisfying angular momentum and gauge charge conservation.
- The cross-section is comparable to the Rubakov-Callan effect, suppressed only by the QCD scale.
Conclusions:
- The proposed pairwise entangled quark state resolves the long-standing positron-monopole scattering mystery.
- This novel state is only observable in theories with more than two dimensions, explaining its absence in previous 2D models.
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