I had the realization that I can reduce my concerns about radial-velocity fitting (given a spectrum) to the problem of centroiding a single spectral line, and then scale up using information theory. So there is a paper to write! I sketched an abstract.
In the morning, Andrei Mesinger (SNS) gave a talk about the epoch of reionization. He argued fairly convincingly that, between Planck, Lyman-alpha emission from very high-redshift quasars and galaxies, and the growth of dark-matter structure, the epoch of reionization is pretty well constrained now, around redshift of 7 to 8. The principal observation (from my perspective) is that the optical depth to the surface of last scattering is close to the minimum possible value (given what we know out to redshifts of 5 or 6). He discussed also what we will learn from 21-cm projects, and—like Colin Hill a few weeks ago—is looking for the right statistics. I really have to start a project that finds decisive (and symmetry-constrained) summary statistics, given simulations!