A Portable Modeler of Lensed Quasars

We introduce and implement two novel ideas for modeling lensed quasars. Thefirst idea is to require different lenses to agree about H_0. This means thatsome models for one lens can be ruled out by data on a different lens. Weexplain 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%-confidenceestimate of 1/H_0=14.6_{-1.7}^{+9.4} Gyr (H_0=67_{-26}^{+9} km/s/Mpc) assumingOmega_M=0.3, Omega_Lambda=0.7. The other example models the time-delay doubles1520+530, 1600+434, 1830-211, and 2149-275, which gives1/H_0=14.5_{-1.5}^{+3.3} Gyr (H_0=67_{-13}^{+8} km/s/Mpc). Our second idea isto write the whole modeling software as a highly interactive Java applet, whichcan be used both for coarse-grained results inside a browser and forfine-grained results on a workstation. Several obstacles come up in trying toimplement a numerically-intensive method thus, but we overcome them.