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C02.1 · Computations

Section of C02.1 — The cubic norm, characteristic identity and the real multiplication operator. Section object E-C02.1.computations · kind COMPUTATION · cites no record · attestation inherited from the article (R69).

← Derivation · Interpretation →

The test object is the full matrix-defined Jordan product and its actual real multiplication lift. The cubic and Jordan certificates are generic polynomial calculations; the split-Hermitian witness and diagonal counterexample are exact specified elements. The source's old numerical kernels are not imported, so no agreement with their unseen basis conventions is claimed.

The command actually executed was: ```sh python CHATGPT_D1258_C02_1_CHECKS_S310.py ``` Settings: exact SymPy rational/symbolic arithmetic; no floating-point tolerances, no external numerical data files, no network calls, no optimized Python (`-O`). The coordinates and formulas above are the scientific inputs. Runtime versions are printed in stdout. The script SHA-256 is `69fb7790811e19318e0850e0d2cb9704f54f4e3c18948b8704bef70cf72efed1`; stdout SHA-256 is `7e376baeb9b9b709f742d4d432b985d5889d2c27294cade75170e292c4529ef5`. An identical-process rerun is a reproducibility check, not the independent house implementation required by the contract.

Complete standalone code: ```python """D1258 C02.1. Full generic cubic element certificate and operator controls."""

from itertools import product, combinations, permutations from collections import Counter import json import platform import sympy as S if not __debug__: raise SystemExit("Do not use -O: assertions are required.") def report(key, value): print(key + " = " + str(value)) def va(x,y): return tuple(a+b for a,b in zip(x,y)) def vn(x): return tuple(-a for a in x) def vs(x,y): return va(x,vn(y)) def sc(k,x): return tuple(k*a for a in x) def dot(x,y): return sum(a*b for a,b in zip(x,y)) def cross(x,y): return (x[1]*y[2]-x[2]*y[1],x[2]*y[0]-x[0]*y[2],x[0]*y[1]-x[1]*y[0]) def qm(p,r): a,b,c,d=p; e,f,g,h=r return (a*e-b*f-c*g-d*h,a*f+b*e+c*h-d*g, a*g-b*h+c*e+d*f,a*h+b*g-c*f+d*e) def qb(p): return (p[0],-p[1],-p[2],-p[3]) O_NAMES=("1","e1","e2","e3","f1","f2","f3","l") OB=[tuple(S.Integer(i==j) for i in range(8)) for j in range(8)] OZ=(S.Integer(0),)*8 def obar(x): return (x[0],)+vn(x[1:]) def omul(x,y,epsilon=1): # Same basis as D1256: f_i=-e_i*l, not +e_i*l. p=x[:4]; q=(x[7],)+vn(x[4:7]) r=y[:4]; s=(y[7],)+vn(y[4:7]) first=va(qm(p,r),sc(epsilon,qm(qb(s),q))) second=va(qm(s,p),qm(q,qb(r))) return first+vn(second[1:])+(second[0],) def onorm(x,epsilon=1): return sum(a*a for a in x[:4])-epsilon*sum(a*a for a in x[4:]) def to_zorn(x): return (x[0]+x[7],)+va(x[1:4],x[4:7])+vs(x[4:7],x[1:4])+(x[0]-x[7],) def from_zorn(z): a=z[0]; u=z[1:4]; v=z[4:7]; b=z[7] return ((a+b)/2,)+sc(S.Rational(1,2),vs(u,v))+sc(S.Rational(1,2),va(u,v))+((a-b)/2,) def zmul(z,w): a=z[0]; u=z[1:4]; v=z[4:7]; b=z[7] c=w[0]; U=w[1:4]; V=w[4:7]; d=w[7] return (a*c+dot(u,V),)+va(va(sc(a,U),sc(d,u)),cross(v,V))+vs(va(sc(c,v),sc(b,V)),cross(u,U))+(dot(v,U)+b*d,) def zero_vector(v): return all(S.expand(a)==0 for a in v) def inertia(M): """Exact rational symmetric congruence elimination; no eigenvalue tolerance.""" A=S.Matrix(M); assert A==A.T positive=negative=null=0 while A.rows: k=next((i for i in range(A.rows) if A[i,i]!=0),None) if k is None: pair=next(((i,j) for i in range(A.rows) for j in range(i+1,A.rows) if A[i,j]!=0),None) if pair is None: null+=A.rows; break i,j=pair P=S.eye(A.rows); P[j,i]=1 A=P.T*A*P k=i inds=[k]+[i for i in range(A.rows) if i!=k] A=A.extract(inds,inds); d=A[0,0] assert d.is_positive or d.is_negative positive+=int(bool(d>0)); negative+=int(bool(d<0)) v=A[1:,0]; A=A[1:,1:]-(v*v.T)/d return (positive,negative,null)

def jmat(A): a,b,c=A[:3]; z=A[3:11]; y=A[11:19]; x=A[19:27] return [[sc(a,OB[0]),z,obar(y)],[obar(z),sc(b,OB[0]),x],[y,obar(x),sc(c,OB[0])]] def jvec(M): assert all(zero_vector(M[i][i][1:]) for i in range(3)) assert all(zero_vector(vs(M[i][j],obar(M[j][i]))) for i in range(3) for j in range(i+1,3)) return tuple(M[i][i][0] for i in range(3))+tuple(M[0][1])+tuple(M[2][0])+tuple(M[1][2]) def mm(A,B): return [[va(va(omul(A[i][0],B[0][j]),omul(A[i][1],B[1][j])),omul(A[i][2],B[2][j])) for j in range(3)] for i in range(3)] def jp(A,B): X=jmat(A); Y=jmat(B); XY=mm(X,Y); YX=mm(Y,X) return jvec([[sc(S.Rational(1,2),va(XY[i][j],YX[i][j])) for j in range(3)] for i in range(3)]) JB=[tuple(S.Integer(i==j) for i in range(27)) for j in range(27)] JI=va(va(JB[0],JB[1]),JB[2]); JZ=(S.Integer(0),)*27 def tr(A): return sum(A[:3]) def sig(A): a,b,c=A[:3];z=A[3:11];y=A[11:19];x=A[19:27] return a*b+a*c+b*c-onorm(x)-onorm(y)-onorm(z) def jnorm(A): a,b,c=A[:3];z=A[3:11];y=A[11:19];x=A[19:27] return a*b*c-a*onorm(x)-b*onorm(y)-c*onorm(z)+2*omul(omul(z,x),y)[0] def sharp(A): return va(vs(jp(A,A),sc(tr(A),A)),sc(sig(A),JI)) def L(A): return S.Matrix.hstack(*[S.Matrix(jp(A,e)) for e in JB]) def brief(A): return {i:S.simplify(a) for i,a in enumerate(A) if S.simplify(a)!=0}

report("environment", {"python":platform.python_version(),"sympy":S.__version__}) report("data_basis","Declared H3(CD-split) product; no banked arrays.") X=S.symbols("A0:27") XX=jp(X,X) ss=S.expand((tr(X)**2-tr(XX))/2) assert S.expand(ss-sig(X))==0 Q=sharp(X) R=vs(jp(X,Q),sc(jnorm(X),JI)) res=[S.Poly(S.expand(r),*X) for r in R] assert all(r.is_zero for r in res) report("generic.cubic_coordinate_polynomials_zero",len(res)) report("generic.norm_degree",S.Poly(S.expand(jnorm(X)),*X).total_degree()) report("generic.norm_monomials",len(S.Poly(S.expand(jnorm(X)),*X).terms())) # Differential identity: gradient N paired with trace metric equals adjoint. B=S.diag(*([1]*3+[2*onorm(e) for e in OB]*3)) grad=S.Matrix([S.diff(jnorm(X),x) for x in X]) gradres=grad-B*S.Matrix(Q) assert all(S.expand(t)==0 for t in gradres) report("generic.gradient_N_equals_trace_metric_sharp",True) report("trace_form.inertia(+,-,0)",inertia(B))

# Universal Jordan identity: [L_X,L_(X^2)]=0 coefficientwise for generic X. LX=L(X); LX2=L(tuple(S.expand(z) for z in XX)) comm=LX*LX2-LX2*LX assert all(S.expand(z)==0 for z in comm) report("Jordan_identity.generic_commutator_coordinate_polynomials_zero",len(comm))

# Exact linear-in-A trace-selfadjoint identity on every basis generator. for e in JB: Le=L(e) assert Le.T*B==B*Le report("trace_selfadjoint.basis_operator_checks",len(JB)) # A real multiplication matrix is trace-form self-adjoint, not Euclidean symmetric. D=tuple(S.Integer(i%5-2) for i in range(27)); M=L(D) assert M.T*B==B*M report("sample.L_dimension",M.shape) report("sample.L_trace_selfadjoint",True) report("sample.L_Euclidean_symmetric",M==M.T) # Diagonal counterexample to p_A(L_A)=0. diag=sc(1,JB[0]);diag=va(va(diag,sc(2,JB[1])),sc(3,JB[2])) Ld=L(diag); opres=Ld**3-tr(diag)*Ld**2+sig(diag)*Ld-jnorm(diag)*S.eye(27) assert not opres.is_zero_matrix report("diagonal123.Jordan_cubic_residual",brief(vs(jp(diag,sharp(diag)),sc(jnorm(diag),JI)))) report("diagonal123.L_spectrum",sorted(Ld.eigenvals().items(),key=lambda t:t[0])) report("diagonal123.operator_cubic_nonzero_entries",sum(x!=0 for x in opres)) report("diagonal123.operator_cubic_on_J12_scalar",opres[3,3]) # Hermitian split witness W12(l); l^2=1 but n(l)=-1. W=JB[10]; W2=jp(W,W) assert W2==vn(va(JB[0],JB[1])) assert va(va(W2,jp(JB[0],JB[0])),jp(JB[1],JB[1]))==JZ lam=S.symbols("lambda") p=lam**3-tr(W)*lam**2+sig(W)*lam-jnorm(W) report("split_witness.A_squared",brief(W2)) report("split_witness.nonzero_square_sum_zero",True) report("split_witness.element_characteristic",S.factor(p)) report("split_witness.element_roots",S.solve(p,lam)) LW=L(W) report("split_witness.L_characteristic",S.factor(LW.charpoly(lam).as_expr())) assert LW.T*B==B*LW report("split_witness.L_trace_selfadjoint",True) report("split_witness.L_Euclidean_symmetric",LW==LW.T) # Jordan identity sampled on explicitly deterministic integer pairs, not a universal proof. count=0 for k in range(6): A=tuple(S.Integer((i*i+3*k*i+k)%5-2) for i in range(27)) Y=tuple(S.Integer((3*i*i+k*i+2)%5-2) for i in range(27)) A2=jp(A,A) assert zero_vector(vs(jp(A2,jp(A,Y)),jp(A,jp(A2,Y)))) count+=1 report("Jordan_identity.sample_pairs_passed",count) report("Jordan_identity.universal_product_proof","Coefficientwise generic polynomial certificate, not inferred from samples.") report("banked_array_alignment","NOT VERIFIED") ```

Actual stdout (not an expected-output fixture): ```text environment = {'python': '3.13.5', 'sympy': '1.14.0'} data_basis = Declared H3(CD-split) product; no banked arrays. generic.cubic_coordinate_polynomials_zero = 27 generic.norm_degree = 3 generic.norm_monomials = 89 generic.gradient_N_equals_trace_metric_sharp = True trace_form.inertia(+,-,0) = (15, 12, 0) Jordan_identity.generic_commutator_coordinate_polynomials_zero = 729 trace_selfadjoint.basis_operator_checks = 27 sample.L_dimension = (27, 27) sample.L_trace_selfadjoint = True sample.L_Euclidean_symmetric = False diagonal123.Jordan_cubic_residual = {} diagonal123.L_spectrum = [(1, 1), (3/2, 8), (2, 9), (5/2, 8), (3, 1)] diagonal123.operator_cubic_nonzero_entries = 16 diagonal123.operator_cubic_on_J12_scalar = 3/8 split_witness.A_squared = {0: -1, 1: -1} split_witness.nonzero_square_sum_zero = True split_witness.element_characteristic = lambda*(lambda**2 + 1) split_witness.element_roots = [0, -I, I] split_witness.L_characteristic = lambda**9*(lambda**2 + 1)*(4*lambda**2 + 1)**8/65536 split_witness.L_trace_selfadjoint = True split_witness.L_Euclidean_symmetric = False Jordan_identity.sample_pairs_passed = 6 Jordan_identity.universal_product_proof = Coefficientwise generic polynomial certificate, not inferred from samples. banked_array_alignment = NOT VERIFIED ```

← Derivation · Interpretation →

Receipt, script and stdout: on the article page. Registrar master sha256 01d1a5873ede42f5b2c5f4fdcee3a4a74c09a14b99a0deea86a60ebd9c821033 · BUILD_STAMP S371a · 2026-09-26 22:53Z · master 01d1a5873ede42f5 · cut 9dcc6ce9a8ee3e02