On the strong-CP problem and its axion solution in torsionful theories
Arnold Sommerfeld Center, Ludwig-Maximilians-Universität München, Theresienstraße 37, 80333, Munich, Germany
Accepted: 4 June 2018
Published online: 11 June 2018
Gravitational effects may interfere with the axion solution to the strong-CP problem. We point out that gravity can potentially provide a protection mechanism against itself, in the form of an additional axion-like field associated with torsion.
© The Author(s), 2018