The day started with a discussion or break-out about making a latent-variable structure for the incredible result by Guy Davies (Birmingham) that the power-spectra of red-giants in an open cluster lie on a one-dimensional locus. Details include: He is only looking at the overall envelope of the power spectrum, parameterized by 8-ish parameters. His 8-ish parameters follow a one-dimensional locus of power laws with respect to each other, except one. That one is the white-noise level, which makes sense is different. So he has a two-dimensional model that seems to fit extremely well every single star power spectrum in an open cluster observed by Kepler!
This discussion merged into a longer discussion, code-named Light-Curve Cannon with contributions from many people looking at how time-domain behavior of stars on different time scales can be used to predict or infer stellar parameters. It is extremely promising that TESS-like time-domain data will be able to tell you stellar parameters at comparable precision to contemporary spectroscopic modeling! Ruth Angus (Columbia) did a great job of bringing together the threads in these discussions: There are many papers to write.
The day ended with a wrap-up in which everyone contributed one slide and spoke for less than two minutes. Here are the wrap-up slides. They only give you the tiniest hint at all the things that happened this week!
Thank you to Dan Foreman-Mackey (Flatiron) and the Flatiron CCA staff and the Simons Foundation events staff for an absolutely great meeting. In particular, Foreman-Mackey's vision, leadership, technical abilities, and good nature got everyone participating and working together. That's community building.