E1b-pm — method-neutral H1 on gravity fields (PM N-body): mass coverage at matched spine length

Setup: 8 PM N-body boxes (128³, EdS, a: 0.1→1). Criterion needs no reference skeleton: fraction of all 128³ particles within r₀=3.0 vox of the spine set, spine length matched at 2400 vox. Note the spine budget covers only ~4% of the volume if spread randomly — differences measure how well spines sit on mass.

n_gal	method	mass coverage	band coverage (2<ρ<20)	Δband vs hessian (p)	Δband vs lift_b0 (p)
5000	hessian	0.4840 ± 0.0224	0.2969 ± 0.0172	—	+0.0557 (0.0078)
5000	lift_s3	0.4727 ± 0.0159	0.2924 ± 0.0117	-0.0045 (0.55)	+0.0512 (0.0078)
5000	lift_s45	0.4448 ± 0.0206	0.2703 ± 0.0146	-0.0267 (0.0078)	+0.0291 (0.0078)
5000	lift_b0	0.4105 ± 0.0242	0.2412 ± 0.0196	-0.0557 (0.0078)	—
20000	hessian	0.5228 ± 0.0161	0.3329 ± 0.0094	—	+0.0496 (0.0078)
20000	lift_s3	0.4993 ± 0.0137	0.3102 ± 0.0067	-0.0228 (0.0078)	+0.0268 (0.016)
20000	lift_s45	0.4915 ± 0.0173	0.3047 ± 0.0128	-0.0282 (0.0078)	+0.0214 (0.0078)
20000	lift_b0	0.4662 ± 0.0151	0.2833 ± 0.0127	-0.0496 (0.0078)	—