Gauged M-flation, its UV sensitivity and Spectator Species
  In this paper we study gauged M-flation, an inflationary model in which
inflation is driven by three NxN scalar field matrices in the adjoint
representation of U(N) gauge group. We focus our study on the gauged M-flation
model which could be derived from the dynamics of a stack of D3-branes in
appropriate background flux. The background inflationary dynamics is unaltered
compared to the ungauged case of [arXiv:0903.1481[hep-th]], while the spectrum
of "spectator species", the isocurvature modes, differs from the ungauged case.
Presence of a large number of spectators, although irrelevant to the slow-roll
inflationary dynamics has been argued to lower the effective UV cutoff
$\Lambda$ of the theory from the Planck mass, invalidating the main advantage
of M-flation in not having super-Planckian field values and unnaturally small
couplings. Through a careful analysis of the spectrum of the spectators we
argue that, contrary to what happens in N-flation models, M-flation is still UV
safe with the modified (reduced) effective UV cutoff $\Lambda$, which we show
to be of order (0.5-1)x10^{-1} M_{pl}. Moreover, we argue that the string scale
in our gauged M-flation model is larger than $\Lambda$ by a factor of 10 and
hence one can also neglect stringy effects. We also comment on the stability of
classical inflationary paths in the gauged M-flation.
