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Frame 3: Algebraic Transformation & Symmetry-Induced Cancellation Removal

Frame 3: Algebraic Transformation & Symmetry-Induced Cancellation Removal
Eng. Abdulla M. N. Al-Jabri — Sana'a, Yemen | October 2026
v7.1 — 2026-10-25

Opening — Problem, Achievement, Type of Evidence

Problem

How does the asymmetric envelope \(g(u)\) modify the transition elements in the algebraic structure, and how does the choice of inner product affect the results — while distinguishing the symmetry proof from the numerical computation?

Achievement

Change of variable \(u=2\pi/x\); derivation of the envelope \(g(u)\); construction of the algebraic identity \(H_g(gY)=-gY''\); proof that the symmetry of \(D(u)\) forces \(\mathcal{A}_{13}^{(0)}=0\) in the reference model; computation of \(\mathcal{A}_{13}\) and \(\mathcal{A}_{12}\) at \(x_p=21\) (ratio \(R_{13/12}\approx0.60352\)); sensitivity of \(x_p\); comparison of inner-product effects.

Type of Evidence

Exact differential identity on the interior domain where \(g>0\) is smooth and \(p\) is defined. Exact symmetry argument in the reference model. Numerical computations via scipy.integrate.quad with documented tolerance and reproducible code. Definition of the appropriate Hilbert space (due to \(1/g^2\) singularities at the endpoints) remains an open question.

1. Purpose of Frame 3

🔗 The journey across frames:
In Frame 1, we studied the raw mathematical code through the function \(Z(x)\). In the Bridge, we linked the physical scales. Now, in Frame 3, we test whether the algebraic structure of the envelope \(g(u)\) can remove the cancellation induced by symmetry in the matrix elements — which may open the door to new interpretations of spectral transitions.

2. Algebraic Transformation of the Operator and Eigenvalue Relation

Introduce the change of variable \(u = 2\pi/x\), so that the function becomes:

\[ Z(u) = g(u) \sin(u) \]

where the envelope is:

\[ g(u) = \left(\frac{u}{2\pi}\right)^5 \ln\left(\frac{2\pi}{u}\right) e^{-2\pi/(21u)} \]

If we define \(p(u) = g'(u)/g(u)\), the explicit formula is:

\[ p(u) = \frac{5}{u} - \frac{1}{u \ln(2\pi/u)} + \frac{2\pi}{21u^2} \]

The following operator satisfies the algebraic identity:

\[ H_g = -\frac{d^2}{du^2} + 2p(u)\frac{d}{du} + p'(u) - p(u)^2 \]

and satisfies: \(H_g(gY) = g(-Y'')\). This means that if \(-Y_n'' = \lambda_n Y_n\), then \(H_g(gY_n) = \lambda_n(gY_n)\).

Interpretation of the operator: The identity \(H_g(gY) = g(-Y'')\) establishes an exact algebraic relation on the interior domain where \(g>0\) is smooth and \(p\) is defined. It provides the foundation for studying the corresponding spectral problem.

However, the identity alone does not produce a complete eigenvalue problem: the domain of the operator and the boundary conditions must be specified independently. Moreover, the values \(-Y_n'' = \lambda_n Y_n\) follow directly from the choice \(Y_n = \sin(nu/2)\) with \(\lambda_n = n^2/4\), and are not a spectral result independent of that choice.

3. Symmetry-Induced Cancellation Removal

In physics, "selection rules" forbid certain transitions due to symmetry under reflection. In our domain \(u \in (0, 2\pi)\), the reflection is \(\hat{P}u = 2\pi - u\).

Under reflection about the midpoint of the domain, \(\hat{P}u = 2\pi - u\), the transition operator \(D(u) = \cos(u/2)\) transforms to \(-D(u)\). Combined with the parity of the base states, \(Y_n(2\pi-u) = (-1)^{n+1}Y_n(u)\), this symmetry forces the reference element \(\mathcal{A}_{13}^{(0)}\) to vanish in the base model.

But the envelope \(g(u)\) is not symmetric under this reflection:

\[ g(u) \neq g(2\pi - u) \]

Introducing the asymmetric envelope removes the symmetry argument that forced \(\mathcal{A}_{13}^{(0)} = 0\) in the reference model. That alone is not sufficient to guarantee that the integral is nonzero, but the numerical computation under the current definitions gives \(\mathcal{A}_{13} \neq 0\) at \(x_p=21\).

4. Transition Elements Test

We choose the transition operator \(D(u) = \cos(u/2)\). For full documentation and reproducibility, we define the base states \(Y_n(u)\) and the normalized states \(\Psi_n(u)\) using the unweighted measure (\(du\)) as follows:

\[ Y_n(u) = \sin\left(\frac{nu}{2}\right), \qquad n=1,2,3,\ldots \] \[ \Psi_n(u) = \frac{g(u)Y_n(u)}{\sqrt{N_n}}, \qquad N_n = \int_0^{2\pi} g(u)^2 Y_n(u)^2 \, du \]

The matrix elements and their ratio are then defined by:

\[ \mathcal{A}_{mn} = \int_0^{2\pi} \Psi_m(u) D(u) \Psi_n(u) \, du, \qquad R_{13/12} = \frac{|\mathcal{A}_{13}|^2}{|\mathcal{A}_{12}|^2} \]
Mathematical result: In the reference model without envelope, the symmetry forces \(\mathcal{A}_{13}^{(0)} = 0\). The element between the first and second states has a value that depends on the normalization:
  • By direct integration of the two unnormalized states \(Y_1, Y_2\): \(\displaystyle \int_0^{2\pi} Y_1(u)D(u)Y_2(u)\,du = \frac{\pi}{2}\).
  • After normalizing the reference states \(Y_1, Y_2\) to norm \(\sqrt{\pi}\) in \(L^2(0,2\pi)\): \(\mathcal{A}_{12}^{(0)} = \dfrac{\pi/2}{\pi} = \dfrac{1}{2}\).
In the model with the envelope, using the normalized states \(\Psi_n\) defined above, the numerical computation gives \(\mathcal{A}_{13} \neq 0\) (negative under the chosen definitions). At \(x_p=21\): \[ R_{13/12} = \frac{|\mathcal{A}_{13}|^2}{|\mathcal{A}_{12}|^2} \approx 0.60352 \quad (60.35\%) \] This is a numerical ratio specific to the model, the normalization, and the transition operator fixed here; it is not by itself a physical prediction or an empirical value.

Dependence of the ratio on \(x_p\) under the chosen definitions:

To study the dependence of the ratio on the parameter \(x_p\), it was computed at several values. The results show a smooth variation over the tested range, with no special behavior visible at \(x_p=21\).

\(x_p\)\(R_{13/12}\)Note
100.61417Smooth variation
150.60742Smooth variation
210.60352Reference value
300.60056Smooth variation
500.59778Smooth variation
Limits of what the sensitivity table establishes. The values shown indicate a smooth variation of the ratio over the tested range; they do not, by themselves, establish that \(x_p = 21\) is a maximum, minimum, or mathematically distinguished value. Also, the error estimates reported by adaptive quad are practical numerical estimates, not rigorous guaranteed error bounds.
Python / SciPy Script
import numpy as np
from scipy.integrate import quad

def g(u, xp=21.0):
    if u <= 0 or u >= 2*np.pi: return 0.0
    return ((u / (2*np.pi))**5) * np.log(2*np.pi / u) * np.exp(-2*np.pi / (xp * u))

def Y(n, u): return np.sin(n * u / 2.0)
def D(u): return np.cos(u / 2.0)

def norm_integrand(u, n, xp): return (g(u, xp) * Y(n, u))**2

def matrix_element_integrand(u, m, n, xp, N_m, N_n):
    psi_m = g(u, xp) * Y(m, u) / np.sqrt(N_m)
    psi_n = g(u, xp) * Y(n, u) / np.sqrt(N_n)
    return psi_m * D(u) * psi_n

def calculate_ratio(xp):
    print(f"--- Computation at x_p = {xp} ---")
    N_1, err_N1 = quad(norm_integrand, 0, 2*np.pi, args=(1, xp), limit=200)
    N_2, err_N2 = quad(norm_integrand, 0, 2*np.pi, args=(2, xp), limit=200)
    N_3, err_N3 = quad(norm_integrand, 0, 2*np.pi, args=(3, xp), limit=200)

    print(f"N_1 = {N_1:.10f} (err: {err_N1:.1e})")
    print(f"N_2 = {N_2:.10f} (err: {err_N2:.1e})")
    print(f"N_3 = {N_3:.10f} (err: {err_N3:.1e})")

    A_12, err_A12 = quad(matrix_element_integrand, 0, 2*np.pi, args=(1, 2, xp, N_1, N_2), limit=200)
    A_13, err_A13 = quad(matrix_element_integrand, 0, 2*np.pi, args=(1, 3, xp, N_1, N_3), limit=200)

    print(f"A_12 = {A_12:.8f} (err: {err_A12:.1e})")
    print(f"A_13 = {A_13:.8f} (err: {err_A13:.1e})")

    R = (abs(A_13)**2) / (abs(A_12)**2)
    print(f"R_13/12 = {R:.8f}\n")
    return R

x_values = [10, 15, 21, 30, 50]
for xp in x_values:
    calculate_ratio(xp)
Terminal Output (Numerical Results)
--- Computation at x_p = 10 ---
N_1 = 0.0030709680 (err: 2.1e-14)
N_2 = 0.0048258897 (err: 2.0e-14)
N_3 = 0.0042376174 (err: 2.0e-14)
A_12 = 0.62678855 (err: 1.2e-14)
A_13 = -0.49120653 (err: 1.1e-14)
R_13/12 = 0.61416656

--- Computation at x_p = 15 ---
N_1 = 0.0033843304 (err: 2.1e-14)
N_2 = 0.0052677281 (err: 2.0e-14)
N_3 = 0.0046153844 (err: 2.0e-14)
A_12 = 0.62379990 (err: 1.2e-14)
A_13 = -0.48617326 (err: 1.1e-14)
R_13/12 = 0.60742342

--- Computation at x_p = 21 ---
N_1 = 0.0035779945 (err: 2.1e-14)
N_2 = 0.0055384080 (err: 2.0e-14)
N_3 = 0.0048466511 (err: 2.0e-14)
A_12 = 0.62207485 (err: 1.2e-14)
A_13 = -0.48326669 (err: 1.1e-14)
R_13/12 = 0.60351552

--- Computation at x_p = 30 ---
N_1 = 0.0037307068 (err: 2.1e-14)
N_2 = 0.0057506430 (err: 2.0e-14)
N_3 = 0.0050279116 (err: 2.0e-14)
A_12 = 0.62077276 (err: 1.2e-14)
A_13 = -0.48107216 (err: 1.1e-14)
R_13/12 = 0.60055827

--- Computation at x_p = 50 ---
N_1 = 0.0038792969 (err: 2.1e-14)
N_2 = 0.0059561711 (err: 2.0e-14)
N_3 = 0.0052033919 (err: 2.0e-14)
A_12 = 0.61955102 (err: 1.2e-14)
A_13 = -0.47901258 (err: 1.1e-14)
R_13/12 = 0.59777767
Comparing inner products:
The computed transition ratio depends on the inner product used to normalize the states. With the unweighted measure \(du\), the current model gives \(R_{13/12} \approx 0.60352\) at \(x_p = 21\). With the weighted inner product \(\langle f,h\rangle_g = \int_0^{2\pi} f^*(u)h(u)/g(u)^2\,du\), the envelope factors reduce algebraically in every transition element (for every pair \((m,n)\); with states of the form \(gY_n\) re-normalized under this inner product), and the symmetry then forces \(\mathcal{A}_{13}\) specifically to vanish — without setting \(\mathcal{A}_{12}\) to zero.

Important qualification. This reduction is an algebraic consequence conditional on the states being in a domain that is square-integrable and normalizable in the weighted space — a point that has not yet been resolved. Since \(g(u) \to 0\) at the endpoints of the domain, the weight \(1/g(u)^2\) becomes singular there, and treating this inner product as a valid Hilbert space for the problem requires verifying integrability, specifying the appropriate domain, and imposing boundary conditions. The vanishing of \(\mathcal{A}_{13}\) under this inner product is therefore a conditional algebraic result, not a complete result about a Hilbert space that has not yet been defined.

The choice of inner product is not merely a matter of form; it fixes the state space and its norm. The contrast between the two inner products shows how the mathematical structure affects the result, and the choice of the physically appropriate inner product still requires derivation from the system being modeled.

5. Results and Scope of the Model

The current model establishes an algebraic transformation of \(Z(u)\), identifies the symmetry responsible for the vanishing of the reference matrix element, and shows how the asymmetric envelope modifies the transition elements under the chosen normalization.

At \(x_p = 21\), the numerical integration gives \(R_{13/12} \approx 0.60352\). The dependence of this ratio on \(x_p\) has been examined, and reproducible computations are provided.

Scope of the result: The reference model establishes that the vanishing of the transition element is due to the reflection symmetry under the stated definitions. Introducing the asymmetric envelope \(g\), and using the unweighted inner product, produces numerically a non-zero element and a ratio at \(x_p = 21\). That value depends on the choice of envelope, states, transition operator, and inner product; it is therefore presented as a result of the specified mathematical model, while its physical interpretation and the determination of the appropriate state space remain subjects for future investigation.

These results motivate further research into the associated spectral problem, the appropriate state space and inner product, and the model's possible significance in physical systems.