Strong lens gravitational time delays are a powerful way to measure cosmological parameters independent of and complementary with other more traditional techniques. After reviewing the basic principles of the method, I will illustrate recent and dramatic improvements in the measurement of the time-delays themselves, and in the modeling of the gravitational potential and line of sight effect, with specific examples, and present the resulting cosmological inference. I will then describe current efforts to improve the precision and accuracy of the method by collecting larger samples of suitable systems and identify, control, and reduce systematic uncertainties (known and unknown unknowns). I will conclude by describing how the LCOGT network could be a uniquely powerful tool for the detemination of gravitational time delays.
LCO Seminar Series, 6740 Cortona Dr, Suite 102, Goleta, CA 93117