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  1. We studied the accretion disc structure in the doubly imaged lensed quasar SDSS J1339+1310 using r -band light curves and UV-visible to near-IR spectra from the first 11 observational seasons after its discovery. The 2009−2019 light curves displayed pronounced microlensing variations on different timescales, and this microlensing signal permitted us to constrain the half-light radius of the 1930 Å continuum-emitting region. Assuming an accretion disc with an axis inclined at 60° to the line of sight, we obtained log( r 1/2 /cm) = 15.4 −0.4 +0.93 . We also estimated the central black hole mass from spectroscopic data. The widthmore »of the C  IV , Mg  II , and H β emission lines, and the continuum luminosity at 1350, 3000, and 5100 Å, led to log( M BH / M ⊙ ) = 8.6 ± 0.4. Thus, hot gas responsible for the 1930 Å continuum emission is likely orbiting a 4.0 × 10 8   M ⊙ black hole at an r 1/2 of only a few tens of Schwarzschild radii.« less
  2. Asking questions is a fundamental aspect of human nature. Languages all around the world encode interrogative constructions. It is therefore incumbent upon semanticists to capture the meaning of questions. However, achieving this goal faces a challenge under a truth conditional approach to meaning, since questions cannot easily be assigned a truth value. Moreover, it is not sufficient to focus only on the questions themselves; one must also determine what counts as a felicitous and informative answer, and how this relates to a speaker's intention in posing a question in a discourse context. How then do semanticists approach an investigation ofmore »questions? In this article, we present the core issues inherent to question‐answer dynamics, review the main approaches to question‐answer meaning, highlight how questions are situated in a discourse context, and explore extensions of questions that highlight the connection between semantics, pragmatics, and human reasoning.« less