Six easy roads to the Planck scale

  title={Six easy roads to the Planck scale},
  author={R. J. Adler},
  journal={American Journal of Physics},
  • R. Adler
  • Published 8 January 2010
  • Physics
  • American Journal of Physics
We give six arguments that the Planck scale should be viewed as a fundamental minimum or boundary for the classical concept of spacetime, beyond which quantum effects cannot be neglected and the basic nature of spacetime must be reconsidered. The arguments are elementary, heuristic, and plausible and as much as possible rely on only general principles of quantum theory and gravity theory. The main goal of the paper is to give physics students and nonspecialists an awareness and appreciation of… 

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