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Putting non Point-like Behavior of Fundamental Particles to Test

Irina Dymnikova·Alexander Sakharov·Juergen Ulbricht·Jiawei Zhao
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Abstract

We review the experimental limits on those hypothetical interactions where the fundamental particles could exhibit non point-like behavior. In particular we have focused on the QED reaction measuring the differential cross sections for the process $ \EEGG $ at energies around 91 GeV and 209 GeV with data collected from the L3 detector from 1991 to 2001. With a global fit L3 set lower limits at $ 95 % $ CL on a contact interaction energy scale parameter $Λ> 1.6 $ TeV, which restricts the characteristic QED size of the interaction region to $ R_{e} < 1.2 \times 10^{-17} $ cm. All the interaction regions are found to be smaller than the Compton wavelength of the fundamental particles. This constraint we use to estimate a lower limit on the internal density of particle-like structure with the de Sitter vacuum core. Some applications of obtained limits to the string and quantum gravity scales are also discussed.

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Irina Dymnikova, Alexander Sakharov, Juergen Ulbricht, Jiawei Zhao. 2003-03-24. Putting non Point-like Behavior of Fundamental Particles to Test. https://arxiv.org/abs/hep-ph/0111302

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