About the isocurvature tension between axion and high scale inflationary
  models
  The present work suggests that the isocurvature tension between axion and
high energy inflationary scenarios may be avoided by considering a double field
inflationary model involving the hidden Peccei-Quinn Higgs and the Standard
Model one. Some terms in the lagrangian we propose explicitly violate the
Peccei-Quinn symmetry but, at the present era, their effect is completely
negligible. The resulting mechanism allows a large value for the axion
constant, of the order $f_a\sim M_p$, thus the axion isocurvature fluctuations
are suppressed even when the scale of inflation $H_{inf}$ is very high, of the
order of $H_{inf}\sim M_{gut}$. This numerical value is typical in Higgs
inflationary models. An analysis about topological defect formation in this
scenario is also performed, and it is suggested that, under certain
assumptions, their effect is not catastrophic from the cosmological point of
view.
