A Portable Modeler of Lensed Quasars

We introduce and implement two novel ideas for modeling lensed quasars. The first idea is to require different lenses to agree about H₀. This means that some models for one lens can be ruled out by data on a different lens. We explain using two worked examples. One example models 1115+080, 1608+656 (time-delay quads) and 1933+503 (a prospective time-delay system) all together, yielding time-delay predictions for the third lens and a 90%-confidence estimate of 1/H₀=14. 6-₁. ₇^+9. 4 Gyr (H₀=67-₂₆^+9 km/s/Mpc) assuming OmegaM=0. 3, OmegaLambda=0. 7. The other example models the time-delay doubles 1520+530, 1600+434, 1830-211, and 2149-275, which gives 1/H₀=14. 5-₁. ₅^+3. 3 Gyr (H₀=67-₁₃^+8 km/s/Mpc). Our second idea is to write the whole modeling software as a highly interactive Java applet, which can be used both for coarse-grained results inside a browser and for fine-grained results on a workstation. Several obstacles come up in trying to implement a numerically-intensive method thus, but we overcome them.