• Corpus ID: 119197148

The Cosmological Constant Problem, Dark Energy, and the Landscape of String Theory

@article{Bousso2012TheCC,
  title={The Cosmological Constant Problem, Dark Energy, and the Landscape of String Theory},
  author={Raphael Bousso},
  journal={arXiv: Cosmology and Nongalactic Astrophysics},
  year={2012}
}
  • R. Bousso
  • Published 1 March 2012
  • Physics
  • arXiv: Cosmology and Nongalactic Astrophysics
In this colloquium-level account, I describe the cosmological constant problem: why is the energy of empty space at least 60 orders of magnitude smaller than several known contributions to it from the Standard Model of particle physics? I explain why the "dark energy" responsible for the accelerated expansion of the universe is almost certainly vacuum energy. The second half of the paper explores a more speculative subject. The vacuum landscape of string theory leads to a multiverse in which… 
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