Landscaping the strong CP problem

  title={Landscaping the strong CP problem},
  author={Nemanja Kaloper and John Terning},
  journal={Journal of High Energy Physics},
A bstractOne often hears that the strong CP problem is the one problem which cannot be solved by anthropic reasoning. We argue that this is not so. Due to nonperturbative dynamics, states with a different CP violating paramenter θ acquire different vacuum energies after the QCD phase transition. These add to the total variation of the cosmological constant in the putative landscape of Universes. An interesting possibility arises when the cosmological constant is mostly cancelled by the membrane… 

Some remarks on anthropic approaches to the strong CP problem

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Irrational monodromies of vacuum energy

  • N. Kaloper
  • Physics
    Journal of High Energy Physics
  • 2019
Abstract We present a theory with axion flux monodromies coupled to gravity, that reduces to the local vacuum energy sequester below the axion mass scales. If the axion potentials include a term

P not PQ

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TCP, quantum gravity, the cosmological constant and all that...

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