#!/usr/bin/env python3
"""
PROVENANCE: PROOF

Computation 117 -- Bridge Premise (B), milestone M8(a):
                   the embedding-norm selection is STRUCTURAL, not empirical
=========================================================================
STATUS (v26.19+): M8(a) of the wave-function attack on Bridge Premise (B).
After the v26.15 referee (P1, accepted), the open content of (B) is the
substrate->SM-coupling matching, and one sub-caveat inside the substrate
side was that the embedding-norm-vs-2pt-residue selection (Comp 114 / M5)
"rests partly on the empirical finiteness of lambda_SM, not a theorem
alone".  This computation removes that empirical crutch.

THE TWO READINGS (recap, Comp 114)
==================================
The wave-function renormalisation is lambda_SM(M_*) = b * Z_phi^2.  Two
candidate substrate objects for Z_phi^2:
  (A) embedding norm   Z_phi^2 = E_mu[exp(-beta_KO X_bar)] -> e^-1   (O(1));
  (B) 2-pt residue     Z_phi^2 = Var_mu(X_bar) = 1/(4D) -> 0.
Comp 114 selected (A) and excluded (B) by noting (B) gives lambda_SM -> 0,
"excluded by the finiteness of the observed quartic" -- an EMPIRICAL
exclusion.

THE STRUCTURAL ARGUMENT (M8a)
=============================
The order parameter X_bar = (1/D) sum_a C_a is an INTENSIVE average.  Its
2-pt residue is its variance, and that variance vanishes as 1/(4D) by the
LAW OF LARGE NUMBERS (P1: the C_a are i.i.d., so the intensive average
self-averages to its mean 1/2 with fluctuations O(1/sqrt(D))).  This
vanishing is a generic large-D effect, not a field-strength.

A field-strength Z_phi is the normalisation relating the substrate field
to the CANONICALLY-NORMALISED emergent field; it must be finite and
non-zero (O(1)) for a canonical emergent field to exist at all.  Reading
(B) sets Z_phi^2 = (an intensive variance) -> 0, i.e. it identifies the
field-strength with a quantity the LLN drives to zero.  That is
structurally inadmissible: a vanishing Z_phi^2 means lambda_SM -> 0 in the
substrate limit D->inf -- a FREE emergent Higgs, no canonical interacting
field.  An intensive order parameter cannot play the role of a
fundamental field whose propagator residue is its susceptibility.

Reading (A) sets Z_phi^2 = the embedding norm (the tempered-vacuum
amplitude of the order-parameter sector, Comp 100), which is O(1) -> e^-1
and DOES normalise a canonical emergent field, giving an interacting
lambda_SM = b e^-1.

The emergent EFT below M_* is the (interacting) Standard Model -- this is
framework premise F4, a STRUCTURAL claim of PST, independent of the
measured value of lambda_SM.  An interacting emergent Higgs requires
Z_phi^2 = O(1); the LLN excludes (B)'s vanishing susceptibility; so the
field-strength is the O(1) embedding norm (A).  The selection is forced
by F4 + the LLN, NOT by the empirical value 0.0927.

This computation verifies the numerics underlying the argument and states
honestly what it does and does not remove.
=========================================================================
"""

import math


def var_xbar(D, p=0.5):
    """2-pt residue reading: Var_mu(X_bar) = p(1-p)/D = 1/(4D) at p=1/2."""
    return p * (1.0 - p) / D


def embedding_norm(D, beta=2.0):
    """Embedding-norm reading: E_mu[exp(-beta X_bar)] = ((1+e^{-beta/D})/2)^D."""
    return ((1.0 + math.exp(-beta / D)) / 2.0) ** D


def main():
    print("=" * 72)
    print("Computation 117: M8(a) -- embedding-norm selection is structural")
    print("=" * 72)
    print()

    b = 0.25            # bare PST quartic (doublet convention)
    e_inv = math.exp(-1.0)

    # ---- 1. the susceptibility vanishes by the LLN (intensive average) ----
    print("1.  THE 2-PT RESIDUE IS AN INTENSIVE VARIANCE -> 0 BY THE LLN")
    print("-" * 72)
    print("    X_bar = (1/D) sum_a C_a, C_a i.i.d. Bernoulli(1/2).")
    print("    Var(X_bar) = 1/(4D); D * Var -> 1/4 (pure self-averaging).")
    print(f"    {'D':>7} {'Var(X_bar)':>14} {'D*Var':>8} {'lambda_SM=b*Var':>18}")
    for D in (10, 100, 1000, 10000):
        v = var_xbar(D)
        print(f"    {D:>7} {v:>14.3e} {D*v:>8.4f} {b*v:>18.3e}")
    print(f"    {'limit':>7} {0.0:>14.3e} {0.25:>8.4f} {0.0:>18.3e}")
    print()
    print("    Reading (B) Z_phi^2 = Var(X_bar) -> 0, so lambda_SM -> 0:")
    print("    a FREE emergent Higgs in the substrate limit. The vanishing")
    print("    is the law of large numbers, not a field-strength.")
    print()

    # ---- 2. the embedding norm is O(1) ----
    print("2.  THE EMBEDDING NORM IS O(1) -> e^-1")
    print("-" * 72)
    print(f"    {'D':>7} {'E_mu[e^-2Xbar]':>16} {'lambda_SM=b*norm':>18}")
    for D in (10, 100, 1000, 10000):
        z = embedding_norm(D)
        print(f"    {D:>7} {z:>16.6f} {b*z:>18.6f}")
    print(f"    {'limit':>7} {e_inv:>16.6f} {b*e_inv:>18.6f}")
    print()
    print("    Reading (A) Z_phi^2 = embedding norm -> e^-1 (O(1)), so")
    print("    lambda_SM -> b e^-1 = 0.0920: an INTERACTING emergent Higgs.")
    print()

    # ---- 3. the structural distinction: variance vs amplitude ----
    print("3.  THE TWO OBJECTS ARE STRUCTURALLY DIFFERENT KINDS")
    print("-" * 72)
    print("    Var(X_bar)        = connected 2-pt function of an INTENSIVE")
    print("                        average; an O(1/D) self-averaging quantity")
    print("                        (LLN); -> 0.  Measures fluctuation SIZE.")
    print("    E_mu[exp(-bX_bar)] = the tempered-vacuum amplitude / MGF of")
    print("                        the order-parameter sector (Comp 100);")
    print("                        O(1); -> e^-1.  Normalises the FIELD.")
    print()
    print("    For a FUNDAMENTAL scalar the field-strength equals the 2-pt")
    print("    residue -- but only because that residue is O(1). For an")
    print("    INTENSIVE order parameter the 2-pt residue is the variance,")
    print("    which the LLN sends to 0; it therefore cannot be a")
    print("    field-strength. The emergent Higgs is the PROJECTED field,")
    print("    normalised by the embedding norm (A), not a fundamental field")
    print("    with residue = susceptibility (B).")
    print()

    # ---- 4. assessment ----
    print("=" * 72)
    print("ASSESSMENT: does M8(a) remove the empirical crutch?")
    print("=" * 72)
    print()
    print("  THE SELECTION, RESTATED STRUCTURALLY:")
    print("   - Reading (B) sets the field-strength to the intensive")
    print("     susceptibility, which -> 0 by the LLN (P1's independence);")
    print("     lambda_SM -> 0, a FREE emergent Higgs. A vanishing Z_phi^2")
    print("     defines no canonical emergent field.")
    print("   - Reading (A) sets it to the O(1) embedding norm; lambda_SM ->")
    print("     b e^-1, a canonical INTERACTING emergent Higgs.")
    print("   - Framework premise F4 (the emergent EFT below M_* is the")
    print("     interacting Standard Model) requires an interacting Higgs,")
    print("     hence Z_phi^2 = O(1), hence reading (A). This uses F4 + the")
    print("     LLN, NOT the measured value lambda_SM = 0.0927.")
    print()
    print("  WHAT THIS REMOVES:")
    print("   The Comp 114 exclusion of (B) said 'lambda_SM is finite")
    print("   (observed), so not (B)'. That empirical-VALUE dependence is")
    print("   removed: (B) is now excluded because it makes the emergent")
    print("   theory free in the substrate limit, contradicting F4 -- a")
    print("   structural premise, not a measurement. The value 0.0927 is no")
    print("   longer an input to the SELECTION (it remains the empirical")
    print("   TEST of the resulting prediction b e^-1 = 0.0920).")
    print()
    print("  WHAT THIS DOES NOT DO (honest residual):")
    print("   - It still rests on F4 (emergent EFT = interacting SM), a")
    print("     framework premise. F4 is structural, but it is a premise;")
    print("     M8(a) trades 'empirical value of lambda_SM' for 'F4', not for")
    print("     nothing.")
    print("   - It does not derive the matching equation lambda_SM(M_*) =")
    print("     b Z_phi^2 itself (Wilsonian threshold matching, F4-F7) from")
    print("     the SM side -- that remains the open step of (B). M8(a)")
    print("     sharpens the substrate-side field-strength selection only.")
    print()
    print("  NET: sub-caveat (a) is closed at the substrate-side level. The")
    print("  embedding-norm reading is forced by P1's LLN + F4, with the")
    print("  measured lambda_SM demoted from an INPUT (to the selection) to")
    print("  a TEST (of the prediction). The remaining open content of (B)")
    print("  is the matching equation to the SM-measured coupling (F4-F7)")
    print("  and the F11 all-orders rigour write-up.")


if __name__ == "__main__":
    main()
