  Using quantum Monte Carlo (QMC) simulations combined with Maximum Entropy
analytic continuation as well as analytical methods, we examine the one- and
two-particle dynamical properties of the Hubbard model on two coupled chains at
small doping.
  The behavior of the single-particle spectral weight $A({\bf k},\omega)$ as a
function of hopping anisotropy $t_\perp/t$ at intermediate interaction strength
is dominated by the transition from one-band behavior at large $t_\perp/t$ to
two-band behavior at small $t_\perp/t$, although interaction effects such as
band-narrowing, a shift of spectral weight to higher energies in the unoccupied
antibonding band and reflected structures due to short-range antiferromagnetic
correlations are also present. A single-particle gap is resolved in the
intermediate $t_\perp/t$ Luther-Emery phase using Density Matrix
Renormalization Group calculations.
  The dynamical spin and charge susceptibilities show features of the expected
bonding-band Luttinger liquid behavior, as well as higher-energy features due
to local excitations between the chains at large $t_\perp/t$, and evolve
towards the behavior of two uncoupled chains as $t_\perp/t$ is reduced. For the
one hole, large $t_\perp/t$ case, we make a detailed comparison between the QMC
data and an approximation based on local rung states.
  At isotropic coupling and somewhat larger doping, we find that the dispersion
of the single-particle bands is essentially unrenormalized from that of the
noninteracting system, and that the spin and charge response functions have
features also seen in random-phase-approximation calculations.
