ept.git/ep_run/holo_ep.py, branch xiang

bp_lm twin control + env forensics probes + holo_a_track_avg (semi-convergence fix, ungated)

2026-07-06T07:22:54+00:00

BP+EMA 2x2 (local, healthy env): qknorm {1.9951, 1.9977}, no-qknorm {1.9728,
1.9732} -> parameterization-matched BP twin tops at ~1.97 vs EP 1.7888: the
equilibrium computation's iteration/depth dividend = 0.18 CE from identical
parameters. External anchor (tuned depth-1 BP, 1.7921): EP at parity.
bp_lm on 107/2.3.1 gave 1.9823 ~= local -> plain backward exonerated on the
pascal env; the 107 divergence (pair/floss/resreg dead by step 600) narrows
to the EP reg/estimator loop. Single-step fingerprints all match (a/b/c/d) ->
suspected intermittent kernel issue; discriminators in flight (torch-2.7 env
probe + delay_hr2's step-2000 reg-on transition).

Co-Authored-By: Claude Fable 5 
Claude-Session: https://claude.ai/code/session_014FAPDWQ49M5Ye3NpTndTpn

holofast: exact halved-jvp AEP track — 1.55x nudged phase, gradient-gate passed

2026-07-05T08:53:57+00:00

holo_a_track computed the doubled-batch jvp/vjp on [v0; -v0] at a shared
anchor zbar — exact antisymmetric redundancy (phase deviations from the
common mode are exact negatives). holo_a_track_fast computes at batch B and
mirrors: single-eval parity 6e-7 (exact); trajectory-level 45% divergence
SHARED with the original's own FD noise floor (1e-6 state noise -> 49%
self-divergence — the 2r=0.04 finite difference amplifies fp noise; training
averages it via pema/momentum). Ship gate: cos(EP,BPTT) orig vs fast
indistinguishable (0.907/0.912, 0.853/0.853, 0.918/0.918). Timing 6.43->4.16s
on the T2=40 nudged phase (contended GPU, relative). --holofast flag,
default off; queued ablation arms deliberately stay on orig for fidelity.

Co-Authored-By: Claude Fable 5 
Claude-Session: https://claude.ai/code/session_014FAPDWQ49M5Ye3NpTndTpn

Initial commit: ept — backprop-free equilibrium transformer (EP)

2026-07-03T10:56:50+00:00

Code (ep_run/), organized docs (docs/{method,campaign,hardware,outreach,paper}),
analysis scripts (scripts/), ONBOARDING.md entry point. Large data/checkpoints
git-ignored (share separately).

Co-Authored-By: Claude Opus 4.8 
Claude-Session: https://claude.ai/code/session_014FAPDWQ49M5Ye3NpTndTpn