Registry · Remark
V.R198
tau-effective
formalized
V.R198 — Sgr A* Shadow Re-Read
The Sgr A* shadow (~52 mu-as diameter) is more time-variable than M87* due to its ~1500x smaller mass and correspondingly shorter dynamical timescale (minutes vs weeks), consistent with tau-Schwarzschild for M = 4.3e6 M_sun at d = 8.3 kpc.
Book V
Part 5
Ch. 42