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Bounds on Plack-scale deformation of CPT from lifetimes and interference

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 نشر من قبل Wojciech Wislicki
 تاريخ النشر 2020
  مجال البحث فيزياء
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 تأليف Wojciech Wislicki




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Deformed relativistic kinematics, expected to emerge in a flat-spacetime limit of quantum gravity, predicts violation of discrete symmetries at energy scale in the vicinity of the Planck mass. Momentum-dependent deformations of the C, P and T invariance are derived from the k{appa}-deformed Poincare algebra. Deformation of the CPT symmetry leads to a subtle violation of Lorentz symmetry. This entails some small but measurable phenomenological consequences, as corrections to characteristics of time evolution: particle lifetimes or frequency of flavour oscillations in two-particle states at high energy. We argue here that using current experimental precisions on the muon lifetime one can bound the deformation parameter k{appa} > 10^14 GeV at LHC energy and move this limit even to 10^16 GeV at Future Circular Collider, planned at CERN. Weaker limits on deformation can be also obtained from interference of neutral mesons. In case of B0s from {Upsilon} decay it amounts to k{appa} > 10^8 GeV at confidence level 99%.

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