The Soccer-Ball Problem

  title={The Soccer-Ball Problem},
  author={Sabine Hossenfelder},
  journal={Symmetry Integrability and Geometry-methods and Applications},
  • S. Hossenfelder
  • Published 9 March 2014
  • Physics
  • Symmetry Integrability and Geometry-methods and Applications
The idea that Lorentz-symmetry in momentum space could be modified but still remain observer-independent has received quite some attention in the recent years. This modified Lorentz-symmetry, which has been argued to arise in Loop Quantum Gravity, is being used as a phenomenological model to test possibly observable effects of quantum gravity. The most pressing problem in these models is the treatment of multi-particle states, known as the 'soccer-ball problem'. This article briefly reviews the… 

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