The Luminosity-Rise Diagram for Fast Blue Optical Transients: A Limit-Derived Exclusion Region and the Observed Population

This paper computes seven fast blue optical transients spanning rise times of three to ten days and compares the resulting quantities with the density and shear ceilings set by the Aldred Limit on the neutron branch, rho_A = 9.72e54 g per cubic centimetre. The absolute floor on rise time is 2.48e-25 seconds, and the luminosity exclusion at ten solar radii is 3.98e+103 watts. Across the full set of cases examined, the astrophysical quantities remain separated from the ceilings by margins of tens of orders of magnitude, so the ceilings do not participate in the dynamics of these events; their role is that of an audit scale against which claimed extremes can be checked arithmetically. All values are computed from stated assumptions and published event properties. This study is simulated and computed, not measured.