Figures 10-12

*Figure 10*

Baryon drag in the inflationary
model. Baryon drag enhances the compressional, here odd, acoustic
peaks. (a) Although diffusion damping at small scales coupled with the
intrinsically small baryon drag effect in low $\Omega_b h^2$ models
hides the effect, the third peak is clearly anomalously high in
all but the most extreme case $\Omega_b h^2 =0.0025$ which is
in clear violation of BBN constraints.
(b) Lowering $\Omega_0 h^2$ also reduces the effect by reducing
the potential fluctuation $\Psi$.{Baryon drag in the inflationary
model. Baryon drag enhances the compressional, here odd, acoustic
peaks. (a) Although diffusion damping at small scales coupled with the
intrinsically small baryon drag effect in low $\Omega_b h^2$ models
hides the effect, the third peak is clearly anomalously high in
all but the most extreme case $\Omega_b h^2 =0.0025$ which is
in clear violation of BBN constraints.
(b) Lowering $\Omega_0 h^2$ also reduces the effect by reducing
the potential fluctuation $\Psi$.

*Figure 11*

Standard rulers and the angular diameter distance. Acoustic features
in the CMB, in particular the peak locations and the damping tail,
act as standard rulers with which a measurement of the curvature
can be made. Thin solid lines represent the $\Omega_0=1$,
$\Lambda=0$ calculation scaled in $\ell$
to account for the projection in the $\Omega_0=0.1$ open and
$\Lambda$ models.

*Figure 12*

Peak spacing and damping scale as a function of $\Omega_0$.
Even allowing for uncertainties in the baryon content (solid shading,
$h=0.5$) and Hubble
constant (dashed shading, $\Omega_bh^2 = 0.0125$),
open models with $\Omega_0 \simlt 0.5$ can be distinguished
from flat ($\Omega_0 + \Omega_\Lambda = 1$) $\Lambda$
models through either scale. The damping scale is
entirely independent of the model for the fluctuations
but may be more difficult to measure
than the peak spacing.