diff --git a/experiments/LOG_DENSITY_ASSESSMENT_2026-09-19.md b/experiments/LOG_DENSITY_ASSESSMENT_2026-09-19.md index eede4eb..3063fb0 100644 --- a/experiments/LOG_DENSITY_ASSESSMENT_2026-09-19.md +++ b/experiments/LOG_DENSITY_ASSESSMENT_2026-09-19.md @@ -108,6 +108,14 @@ log representation itself. The current barotropic Bernoulli equation is a separate modeling choice and does not automatically generalize to varying entropy or composition. +In the current formulation, enthalpy is also an independent trial field. The +prepared pressure operator rejects nonfinite or negative enthalpy at its own +integration points (`libmeanfield/impl/operators/prepared_pressure_force.cpp`, +lines 788–800). Pointwise-positive density alone therefore does not make a +Newton candidate admissible. Any coupled log-density experiment must still test +the enthalpy directions and pressure-preparation obstruction; the frozen +density controls below establish no improvement in that separate guard. + ### A vanishing reference factor Let @@ -242,8 +250,8 @@ but can increase scale disparities across cells and coupled blocks. The small weighted matrices for the exact reference profiles have condition numbers approximately `7.87298`, `16.8523`, and `94.5609` for n=1,1.5,3. These -are three-dimensional local polynomial-space measurements, not estimates of the -stellar Jacobian's condition number. For the fitted exponential controls the +are measurements of 3-by-3 matrices for one-dimensional quadratic trial/test +spaces, not estimates of the stellar Jacobian's condition number. For the fitted exponential controls the corresponding numbers are `6.65377`, `13.7153`, and `74.9786`. The first-order identity `delta rho/rho=delta u` makes a log step a relative