The strong CP problem and discrete symmetries

  title={The strong CP problem and discrete symmetries},
  author={Martin Spinrath},
  journal={Modern Physics Letters A},
We discuss a possible solution to the strong CP problem which is based on spontaneous CP violation and discrete symmetries. At the same time we predict in a simple way the almost right-angled quark unitarity triangle angle (α ≃ 90∘) by making the entries of the quark mass matrices either real or imaginary. To prove the viability of our strategy we present a toy flavour model for the quark sector. 
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