Across a week of seemingly unrelated papers—2D CFT signature rotation, supersymmetric gluing computations, cosmological coactions, and light-bending in dilatonic spacetimes—the common struggle is analytic continuation, the act of extending a quantity from one mathematical domain into another. The non-obvious claim is that this continuation isn't post-hoc technical cleanup but the place where the physics actually lives: questions like whether a quantum gravity theory is ghost-free are answered at the Euclidean-Lorentzian seam, not in the prior computation. The deeper provocation is that the difficulty of Wick rotation signals genuine uncertainty about what mathematical object reality is, undermining any 'only game in town' confidence, while diagrams and their combinatorics increasingly become the primary physical object rather than mere scaffolding.

Topics: analytic continuation, Wick rotation, quantum gravity, twisted cohomology, scattering amplitudes