Test of modified Newtonian dynamics with recent Boomerang data

Purely baryonic dark matter dominated models like modified Newtonian dynamics (MOND) based on modification of Newtonian gravity have been successful in reproducing some dynamical properties of galaxies. More recently, a relativistic formulation of MOND proposed by Bekenstein seems to agree with cosmological large scale structure formation. In this work, we revise the agreement of MOND with observations in light of the new results on the cosmic microwave anisotropies provided by the $2003$ flight of Boomerang. The measurements of the height of the third acoustic peak, provided by several small scale CMB experiments have reached enough sensitivity to severely constrain models without cold dark matter. Assuming that acoustic peak structure in the CMB is unchanged and that local measurements of the Hubble constant can be applied, we find that the cold dark matter is strongly favored with Bayesian probability ratio of about one in two hundred.

Figure 1

This plot shows the experimental data used and a few theoretical spectra. Points with large error-bars were removed from the plot (but actually used in the parameter estimation chains) to maintain clarity. The experiments are as follows: WMAP (bars), VSA (triangles), CBI (crosses), ACBAR (crossed circles), Boomerang (circles). The theoretical graphs plotted are most likely model in our chains for the all CMB data (solid line) and two models picked from best fit models with ${\Omega }_m<0.01$ from each chain sampling WMAP data only. Parameters for dashed model are $({\omega }_b,{\omega }_{\nu },h,n_s)=(0.22,0.096,0.76,0.59)$ and those for the dotted are $(0.22,0.15,0.78,0.43)$. See text for discussion.

Figure 2

This plot shows the marginalized probability distribution for ${\Omega }_{\mathrm{cmd}}$ for the WMAP dataset alone (thin line) and WMAP/VSA/ACBAR/CBI/Boomerang datasets (thick line). Curves are normalized to the same total area under the curve.