On the last day of the Oort meeting, the four groups (which were working to answer four questions posed by Blandford at the beginning) made their presentations. The two groups that did publishable calculations were the Hubble Constant group (my group) and the substructure lensing group. Our group concluded that there is a strict 99-percent upper limit on the Hubble Constant from the known lens systems of 78 km s-1 Mpc-1, found by making the maximal assumption that mass follows light. This limit is much stronger than that from the HST Key Project or any other direct method other than perhaps the baryon acoustic feature in the LRGs.
The substructure group took a skeptical view and showed that there is no absolutely clear evidence in multiple imaging systems for truly dark substructure in dark-matter halos, in the sense that all lenses with magnification anomalies can be explained either by giving mass to luminous substructure or else line-of-sight effects like extinction or scattering.
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