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Chapter 15: EPR Duality (ER=EPR)

15.2 Bell Violation

Bell Violation Theorem Overview

Having established the Bi-Metric structure of the entangled vacuum, we are immediately confronted with the necessity of reconciling this topology with the empirical reality of Bell's Theorem. The standard interpretation of Bell inequality violations posits a breakdown of "Local Realism," suggesting that the universe is either fundamentally non-local or non-real. In the Quantum Braid Dynamics (QBD) framework, we reject this dichotomy. We assert that Realism is preserved—the graph state is definite—and Locality is preserved—information travels exclusively edge-to-edge. The violation arises because "Locality" is historically defined by the emergent manifold metric (dgeod_{geo}), while the quantum system operates according to the intrinsic graph metric (dtopod_{topo}).

We restrict our analysis to the idealized bipartite system (the EPR pair), ignoring detector inefficiencies or loop-hole closures, to isolate the structural mechanism of correlation. We proceed by constructing the causal path of the shared signal, demonstrating that what appears to the relativistic observer as an instantaneous connection across spacelike separation is, in the graph frame, a strictly local interaction mediated by a topological bridge. This derivation effectively demystifies the "spooky action" by proving that the correlation limit is determined not by the distance through the bulk, but by the hop-count of the shortest path. This construction validates the ER=EPR conjecture as a necessary consequence of the graph topology.


15.2.1 Theorem: Violation of Metric Locality (Bell's Theorem)

Establishment of the CHSH Bound Divergence via Topological Shortcuts

It is herein established that for a bipartite system consisting of subsystems AA and BB connected by a topological bridge ABE\ell_{AB} \in E, the correlations between local measurements are bounded exclusively by the algebraic connectivity of the graph GG and are independent of the geodesic separation defined on the emergent manifold MM. Let SS denote the Clauser-Horne-Shimony-Holt (CHSH) correlation parameter derived from the expectation values of local observables. The existence of the bridge edge condition dtopo(A,B)=1d_{topo}(A, B) = 1 necessitates that the upper bound of SS saturates the Tsirelson bound of quantum mechanics rather than the Bell bound of classical local realism:

2<S222 < |S| \le 2\sqrt{2}

provided that the metric divergence condition dgeo(A,B)dtopo(A,B)1\frac{d_{geo}(A, B)}{d_{topo}(A, B)} \gg 1 holds. The violation of the classical inequality S2|S| \le 2 constitutes the physical signature of the topological bridge bypassing the bulk manifold metric.

15.2.1.1 Commentary: Argument Outline

Structure of the Violation of Metric Locality Argument via Path Integral Dominance, Correlation Persistence, and Unitary Constraints

The proof proceeds via Direct Construction, showing that topological shortcuts bypass the bulk metric to violate local realism bounds while respecting algebraic causality.

  1. Path Integral Dominance §15.2.2: The argument demonstrates that transition amplitudes are dominated by paths of minimal hop-count, routing correlations through the shortcut.
  2. Correlation Bridge §15.2.3: The argument derives correlation decay along the graph, proving that topological adjacency preserves quantum coherence across spatial separations.
  3. Tsirelson Bound §15.2.4: The argument applies unitary bounds to the braid algebra to establish the Tsirelson limit as the absolute algebraic correlation ceiling.
  4. Formal Synthesis of Bell Violation §15.2.5: The argument unifies these discrete constraints to calculate the CHSH score, verifying the bi-metric resolution of the EPR paradox.

15.2.2 Lemma: Path Integral Dominance

Establishment of the Shortest Path Principle for Graph Amplitudes in the Geometrogenesis Limit

It is herein established that the transition amplitude A(AB)\mathcal{A}(A \to B) mediating the interaction between two subsystems AA and BB within the causal graph GG is determined strictly by the summation over all directed paths connecting the subsystems. In the Geometrogenesis limit defined by high inverse temperature β\beta \to \infty, this summation is asymptotically dominated by the subset of paths minimizing the topological hop-count. Specifically, if there exists a bridge edge AB\ell_{AB} such that dtopo(A,B)dgeo(A,B)d_{topo}(A, B) \ll d_{geo}(A, B), the transition probability P(AB)P(A \to B) satisfies the dominance condition:

P(AB)ψbridge2[1+O(eα(dgeodtopo))]P(A \to B) \approx |\psi_{bridge}|^2 \cdot \left[ 1 + \mathcal{O}\left( e^{-\alpha(d_{geo} - d_{topo})} \right) \right]

where α\alpha is the action cost per graph edge. This condition enforces that the causal influence propagates effectively exclusively along the topological shortcut.

15.2.2.1 Proof: Amplitude Weight of the Shortest Path

Derivation of Exponential Suppression for Bulk Trajectories

I. The Path Integral Formulation

The propagator K(A,B)K(A, B) on the graph is defined as the sum over all possible causal histories (paths) γ\gamma connecting vertex set AA to vertex set BB, weighted by the complex action S[γ]S[\gamma]:

K(A,B)=γΓ(A,B)eiS[γ]eβE[γ]K(A, B) = \sum_{\gamma \in \Gamma(A, B)} e^{i S[\gamma]} e^{-\beta E[\gamma]}

In the discretized causal graph, the action for a path is proportional to its length (hop-count) L(γ)L(\gamma):

S[γ]L(γ)S[\gamma] \propto L(\gamma)

Assuming a Wick-rotated Euclidean regime for the vacuum state (tunneling amplitude), the weight becomes real and exponential:

W(γ)=eμL(γ)W(\gamma) = e^{-\mu L(\gamma)}

where μ\mu is the mass-gap parameter per edge.

II. Partition of Path Space

The set of all paths Γ(A,B)\Gamma(A, B) is partitioned into two disjoint subsets:

  1. The Bridge Set (Γbridge\Gamma_{bridge}): Paths utilizing the direct topological link AB\ell_{AB}.

    γΓbridge,L(γ)=dtopo1\forall \gamma \in \Gamma_{bridge}, \quad L(\gamma) = d_{topo} \approx 1
  2. The Bulk Set (Γbulk\Gamma_{bulk}): Paths restricted to the emergent manifold geometry (excluding the bridge).

    γΓbulk,L(γ)dgeoN\forall \gamma \in \Gamma_{bulk}, \quad L(\gamma) \ge d_{geo} \approx N

III. Comparative Weight Evaluation

The total amplitude is the sum of contributions from both sets:

Atotal=Abridge+AbulkNbridgeeμ1+Npaths(bulk)eμN\mathcal{A}_{total} = \mathcal{A}_{bridge} + \mathcal{A}_{bulk} \approx N_{bridge} e^{-\mu \cdot 1} + N_{paths}(bulk) e^{-\mu \cdot N}

where Npaths(bulk)N_{paths}(bulk) represents the entropy of paths through the bulk.

IV. Asymptotic Dominance

We evaluate the ratio of contributions in the limit of large bulk separation NN \to \infty:

AbulkAbridgeeSentropy(N)eμNeμ=exp(Sentropy(N)μN)\frac{\mathcal{A}_{bulk}}{\mathcal{A}_{bridge}} \propto \frac{e^{S_{entropy}(N)} e^{-\mu N}}{e^{-\mu}} = \exp\left( S_{entropy}(N) - \mu N \right)

Provided the mass gap μ\mu exceeds the path entropy growth rate (a condition satisfied in the ordered phase of Geometrogenesis Discrete Divergence-Free Geometry §12.3.2), the exponent is negative and scales linearly with NN:

limNAbulkAbridge=0\lim_{N \to \infty} \frac{\mathcal{A}_{bulk}}{\mathcal{A}_{bridge}} = 0

V. Conclusion

The transition amplitude is functionally indistinguishable from the single-edge amplitude. The bulk contribution is exponentially suppressed, confirming that the effective causal channel is the topological bridge.

Q.E.D.

15.2.2.2 Commentary: The Signal Takes the Bridge

Physical Interpretation: The Principle of Least Action in Network Topology

We are witnessing the "Principle of Least Action" in its rawest, most discrete form. In classical mechanics, a particle takes the path that minimizes the action integral. In Quantum Braid Dynamics, the "particle" (the correlation) explores every path, but the "action" is simply the number of rewrite steps required to transport the information.

Consider the choice facing the quantum state:

  1. Path A (The Bulk): Transmit the qubit state by swapping it neighbor-to-neighbor through a billion intermediate nodes (dgeod_{geo}). Each swap introduces a chance for decoherence and costs thermodynamic action. The probability amplitude for this path is ehuge numbere^{-\text{huge number}}.
  2. Path B (The Bridge): Transmit the state across the single stabilizer link (dtopod_{topo}). One swap. Done. The probability amplitude is esmall numbere^{-\text{small number}}.

The math in Proof 15.2.2.1 (§15.2.2.1)is simply formalizing the obvious: the universe is efficient. It doesn't "know" that the bulk path corresponds to a straight line in our emergent 3D space. It only knows that the bridge path is cheaper. The signal "tunnels" through the bulk not because it violates the speed limit, but because it found a wormhole where the speed limit (c=1c=1 hop/tick) gets you there in one tick. To the graph, AA and BB are not far apart; they are touching. The mystery of Bell non-locality is resolved by realizing that "distance" is an emergent statistical cost function, and entanglement is a subsidy that sets that cost to zero.

15.2.2.3 Visual: Bell Shortcut

This visualizes the Path Integral Dominance §15.2.2(Path Integral Dominance)**. In the Bell experiment, a "signal" (correlation) seems to travel instantaneously. QBD resolves this by showing that the "signal" travels at speed (1 hop per tick) along the shortcut. It does not traverse the bulk. The violation of Bell's Inequality is simply the observation that the Graph Metric () creates shorter loops than the Riemannian Metric () allows, bypassing the light cone defined by the bulk.

                  [ SPATIOTEMPORAL GRAPH ]

Time
^
| (Measurement A) (Measurement B)
t=1 | O <=== [1] ===> O
| / \ Bridge / \
| / \ / \
| / \ / \
t=0 | O-------O-------O-------O
| (Bulk) (A) (B) (Bulk)
|
+---------------------------------------------> Space (x)

[1] THE SHORTCUT:
The correlation travels along the bridge edge.
Graph Distance: 1 step.
Time Elapsed: 1 tick.

[2] THE MANIFOLD ILLUSION:
An observer in the Bulk sees A and B separated by
thousands of nodes (Space).

To them, a signal moving from A to B in 1 tick
implies v = dist/time >> c.

QBD Resolution: The speed limit 'c' applies to edges,
not Euclidean distance. The path was just short.


15.2.3 Lemma: Correlation Bridge

Establishment of Correlation Decay Dependence on Topological Adjacency

It is herein established that the magnitude of the connected correlation function C(A,B)C(A, B) between two local observables O^A\hat{O}_A and O^B\hat{O}_B is strictly bounded by the exponential decay of information along the geodesic of the causal graph GG. Let ξ\xi denote the correlation length of the vacuum state. The correlation magnitude satisfies the inequality:

C(A,B)Kexp(dtopo(A,B)ξ)|C(A, B)| \ge \mathcal{K} \cdot \exp\left( -\frac{d_{topo}(A, B)}{\xi} \right)

where K\mathcal{K} is a normalization constant determined by the operator norms. Consequently, the existence of a topological bridge AB\ell_{AB} such that dtopo(A,B)ξd_{topo}(A, B) \ll \xi guarantees the persistence of macroscopic correlations C(A,B)O(1)|C(A, B)| \sim \mathcal{O}(1), irrespective of the divergence of the geometric distance dgeo(A,B)ξd_{geo}(A, B) \gg \xi defined on the emergent manifold.

15.2.3.1 Proof: Correlation Magnitude Calculation

Formal Derivation of the Correlation Function via Minimal Path Dominance

I. Definition of the Correlation Function

The connected correlation function for Pauli observables σ^A\hat{\sigma}_A and σ^B\hat{\sigma}_B acting on qubits at vertices uAu \in A and vBv \in B is defined as the expectation value in the graph state ΨG|\Psi_G\rangle:

C(A,B)=ΨGσ^Aσ^BΨGΨGσ^AΨGΨGσ^BΨGC(A, B) = \langle \Psi_G | \hat{\sigma}_A \otimes \hat{\sigma}_B | \Psi_G \rangle - \langle \Psi_G | \hat{\sigma}_A | \Psi_G \rangle \langle \Psi_G | \hat{\sigma}_B | \Psi_G \rangle

For the stabilizer vacuum state, the expectation value is non-zero if and only if the operator product σ^Aσ^B\hat{\sigma}_A \otimes \hat{\sigma}_B commutes with the stabilizer group S\mathcal{S}.

II. Path Decomposition of the Operator Product

The operator product σ^Aσ^B\hat{\sigma}_A \otimes \hat{\sigma}_B corresponds to the endpoint excitations of a Wilson line (a string of Pauli operators) WγW_{\gamma} extending along a path γ\gamma connecting uu and vv. The correlation magnitude is proportional to the amplitude of the minimal weight string:

C(A,B)maxγΓ(u,v)Wγ|C(A, B)| \propto \max_{\gamma \in \Gamma(u,v)} \left| \langle W_{\gamma} \rangle \right|

The expectation value of a Wilson line of length L(γ)L(\gamma) in a massive phase decays exponentially with length:

WγeL(γ)/ξ\langle W_{\gamma} \rangle \sim e^{-L(\gamma) / \xi}

III. Application of the Bridge Topology

By Path Integral Dominance §15.2.2, the set of paths is dominated by the topological bridge. We evaluate the decay function for the two relevant metrics:

  1. Geometric Decay (The Manifold Limit):

    Lgeo=dgeo(u,v)N    CgeoeN/ξ0L_{geo} = d_{geo}(u, v) \approx N \implies C_{geo} \sim e^{-N/\xi} \to 0
  2. Topological Decay (The Graph Limit):

    Ltopo=dtopo(u,v)=1    Ctopoe1/ξL_{topo} = d_{topo}(u, v) = 1 \implies C_{topo} \sim e^{-1/\xi}

IV. Ratio and Preservation

Assuming the standard ordered phase where ξ1\xi \ge 1 (lattice spacing), the topological correlation evaluates to a constant of order unity:

C(A,B)e1/ξ1|C(A, B)| \approx e^{-1/\xi} \approx 1

This confirms that the topological bridge effectively "short-circuits" the exponential decay that characterizes the bulk manifold, preserving the quantum information against spatial decoherence.

Q.E.D.

15.2.3.2 Commentary: Tunneling Through the Bulk

Physical Interpretation: The Bulk as an Information Insulator

To understand why Bell correlations persist across vast distances, we must view the bulk geometry not as "empty space," but as a physical medium—a "dielectric" of causality. In the QBD framework, the bulk is composed of a dense network of local interactions (the vacuum foam). Transmitting a signal through this medium is expensive; the signal must hop from node to node, and at each step, the noise of the vacuum (the mass gap) eats away at the correlation amplitude. This is why standard correlations decay exponentially with distance (er/ξe^{-r/\xi}). The bulk is an Information Insulator.

An entanglement bridge, however, acts as a Superconducting Wire that punctures this insulator. Because the bridge edge is a direct topological link, the signal bypasses the dissipative medium of the bulk entirely. It does not travel through the intervening space; it travels around it, utilizing a higher-dimensional connection that the 3D manifold cannot represent.

The "Tunneling" metaphor here is topological, not potential-based. The signal doesn't overcome a barrier; it ignores the existence of the barrier. To the entangled particles, the light-years of spacetime separating them are a fiction created by the path-integral statistics of the bulk. They remain in direct contact, shaking hands through the tunnel while the universe expands around them.

15.2.3.3 Visual: Hub-and-Spoke vs Distributed Mesh

This illustrates the Teleportation Protocol §15.3.4(Multipartite Topology)**. It compares two extreme forms of entanglement: the GHZ state (Star Graph) and the W-state or Cluster State (Mesh). This topological distinction determines how "robust" the geometry is. A Hub-and-Spoke geometry is fragile (cut the hub, space collapses), while a Mesh geometry (spacetime) is resilient.

    TYPE A: HUB-AND-SPOKE (GHZ-like)        TYPE B: DISTRIBUTED MESH (Cluster-like)
"Fragile Topology" "Robust Geometry (Spacetime)"

(P2) (P1)--(P2)--(P3)
\ | | |
\ | | |
(P1)----(HUB)----(P3) (P4)--(P5)--(P6)
/ | | |
/ | | |
(P4) (P7)--(P8)--(P9)

* Distance d(P1, P3) = 2 * Distance d(P1, P3) = 2
* DELETE HUB: * DELETE P5:
Total disconnection. P1 can still reach P9 via P4-P7-P8.
Space ceases to exist. Geometry curves, but survives.

=> Gravity requires Mesh Topology (Redundancy).


15.2.4 Lemma: Tsirelson Bound

Establishment of the Maximum Quantum Correlation Limit via Unitary Constraints

It is herein established that while the existence of a topological bridge allows the correlation parameter SS to exceed the classical local realism bound (S2|S| \le 2), the magnitude of SS remains strictly bounded by the geometric constraints of the graph Hilbert space HG\mathcal{H}_G. Specifically, for any set of local observables defined by the braid group algebra BN\mathcal{B}_N, the CHSH correlation is bounded by the Tsirelson limit:

S22|S| \le 2\sqrt{2}

This bound arises from the unitarity of the stabilizer generators and the finite dimensionality of the local link Hilbert space, prohibiting arbitrary "super-quantum" correlations regardless of the graph topology.

15.2.4.1 Proof: Geometric Limits of Braid Deformation

Formal Derivation of the Operator Norm Limit

I. The CHSH Operator Construction

Let A1,A2A_1, A_2 be local observables on subsystem AA, and B1,B2B_1, B_2 be local observables on subsystem BB, corresponding to braid measurements along distinct axes. The Bell operator B\mathcal{B} is defined:

B=A1B1+A1B2+A2B1A2B2\mathcal{B} = A_1 \otimes B_1 + A_1 \otimes B_2 + A_2 \otimes B_1 - A_2 \otimes B_2

The observables satisfy the involutory condition of Pauli operators: Ai2=Bj2=IA_i^2 = B_j^2 = I.

II. The Squared Operator Variance

We evaluate the square of the Bell operator, B2\mathcal{B}^2. Expanding the terms and utilizing the commutativity [Ai,Bj]=0[A_i, B_j] = 0 (enforced by the spatial separation of AA and BB on the graph):

B2=4I+[A1,A2][B1,B2]\mathcal{B}^2 = 4I + [A_1, A_2] \otimes [B_1, B_2]

This step reduces the correlation bound to a geometric limit on the non-commutativity of local measurements.

III. Maximization via Braid Deformation

The commutator of two unitary observables is bounded by the operator norm:

[A1,A2]2and[B1,B2]2\| [A_1, A_2] \| \le 2 \quad \text{and} \quad \| [B_1, B_2] \| \le 2

However, the geometric structure of the local Hilbert space (the Bloch sphere) links these commutators. The maximum eigenvalue of the product term [A1,A2][B1,B2][A_1, A_2] \otimes [B_1, B_2] is achieved when the measurement bases are maximally complementary (rotated by π/4\pi/4). The supremum of the operator square is:

B2=4+4=8\| \mathcal{B}^2 \| = 4 + 4 = 8

IV. The Tsirelson Limit

The bound on the correlation expectation value S=BS = \langle \mathcal{B} \rangle is the square root of the operator norm:

SB2=8=22|S| \le \sqrt{\| \mathcal{B}^2 \|} = \sqrt{8} = 2\sqrt{2}

Thus, even with a direct topological bridge (dtopo=1d_{topo}=1), the algebraic structure of the braid operators prohibits correlations exceeding this value.

Q.E.D.

15.2.4.2 Commentary: Finite Correlation from Finite Connectivity

Physical Interpretation: The Structural Rigidity of Quantum Logic

The Tsirelson Bound (222.8282\sqrt{2} \approx 2.828) is one of the most profound numbers in physics. It asks: "If we can break the speed of light limit using entanglement (violating S2|S| \le 2), why can't we violate it infinitely? Why not S=4|S| = 4?"

The answer lies in the "pixelation" of the graph. The topological bridge is a connection, yes, but it is a connection with a specific, finite bandwidth. It is built from Qubits (two-level systems), not continuous variables. The algebra of these qubits—the way rotations A1A_1 and A2A_2 interact—has a rigid geometry. You cannot align vectors in a Hilbert space to be "more than parallel" or "more than orthogonal."

The bridge bypasses the spatial distance (dgeod_{geo}), allowing the signal to survive. But it cannot bypass the logical geometry of the operators themselves. The value 222\sqrt{2} represents the maximum "tension" the graph can support before the logical consistency of the measurement outcomes breaks down. It is the "speed limit" of the graph's internal logic, distinct from the speed limit of the bulk's external geometry.


15.2.5 Proof: Formal Synthesis of Bell Violation

Formal Verification of the CHSH Inequality Violation via Bi-Metric Topologies

I. The Metric Locality Premise Let the classical bound for the CHSH parameter SclassicalS_{classical} be defined under the assumption of Metric Locality, where the correlation magnitude C(A,B)|C(A, B)| is constrained by the geodesic distance dgeo(A,B)d_{geo}(A, B) through the bulk manifold.

  1. Separation: dgeo(A,B)=Nξd_{geo}(A, B) = N \gg \xi.
  2. Decay: Assuming bulk propagation, C(A,B)eN/ξ0|C(A, B)| \propto e^{-N/\xi} \to 0.
  3. Result: Under the manifold metric constraint, Sclassical02S_{classical} \to 0 \le 2.

II. The Topological Dominance The QBD framework establishes that the physical correlation is governed by the graph action, not the manifold embedding.

  1. Path Selection: By Path Integral Dominance §15.2.2, the transition amplitude is dominated by the topological bridge AB\ell_{AB} where dtopo(A,B)=1d_{topo}(A, B) = 1.
  2. Preservation: By Correlation Bridge Lemma §15.2.3, the short path preserves the correlation magnitude C(A,B)1|C(A, B)| \sim 1 despite the macroscopic geometric separation.

III. The CHSH Evaluation We evaluate the correlation parameter SS for the state Ψbridge|\Psi_{bridge}\rangle using the maximal violation measurement settings (Bell Basis).

S=A1B1+A1B2+A2B1A2B2S = \langle A_1 B_1 \rangle + \langle A_1 B_2 \rangle + \langle A_2 B_1 \rangle - \langle A_2 B_2 \rangle

Substituting the topologically preserved expectation values derived from the braid algebra:

Sgraph=12+12+12(12)=42=22S_{graph} = \frac{1}{\sqrt{2}} + \frac{1}{\sqrt{2}} + \frac{1}{\sqrt{2}} - \left( -\frac{1}{\sqrt{2}} \right) = \frac{4}{\sqrt{2}} = 2\sqrt{2}

IV. Formal Conclusion The effective correlation SgraphS_{graph} satisfies the inequality:

2<Sgraph222 < S_{graph} \le 2\sqrt{2}

The violation of the classical Bell inequality (S2|S| \le 2) is the direct necessary consequence of the Bi-Metric Anomaly. The system violates "Locality" only with respect to the emergent manifold metric dgeod_{geo}; it strictly obeys locality with respect to the intrinsic graph metric dtopod_{topo}.

Q.E.D.

15.2.5.1 Calculation: CHSH Score Verification

Verification of Non-Local Graph Correlation Statistics via CHSH Inequality Testing

Verification of the metric locality violation established in the Bell Violation Theorem Violation of Metric Locality (Bell's Theorem) §15.2.1 is based on the following protocols:

  1. State Preparation: The algorithm initializes the maximally entangled Bell state on a graph topology containing a single stabilizer bridge.
  2. Basis Measurement: The protocol applies rotated local Pauli operators to the boundary vertices to maximize the geometric conflict between measurement bases.
  3. CHSH Parameter Evaluation: The metric computes the four joint correlation expectation values to evaluate the Clauser-Horne-Shimony-Holt parameter. :::
import numpy as np

def verify_chsh_violation():
"""
Simulation 15.2.5.1: CHSH Inequality Verification.

This routine computes the Bell-CHSH correlation parameter S for a bipartite
system connected by a topological bridge (Entangled Singlet/Triplet).
It verifies that the correlation magnitude exceeds the classical manifold
bound (|S| <= 2) and saturates the quantum graph bound (|S| <= 2sqrt(2)).
"""

# -------------------------------------------------------------------------
# 1. State Initialization (The Topological Bridge)
# -------------------------------------------------------------------------
# We define the Bell State |Phi+> = (|00> + |11>) / sqrt(2).
# In QBD, this represents a single edge connecting A and B (d_topo = 1).
psi = np.array([1, 0, 0, 1]) / np.sqrt(2)

# -------------------------------------------------------------------------
# 2. Measurement Operator Definition
# -------------------------------------------------------------------------
# Pauli matrices for spin measurement
Z = np.array([[1, 0], [0, -1]])
X = np.array([[0, 1], [1, 0]])

# Function to create a measurement operator rotated by theta in X-Z plane
def measure_op(theta):
return np.cos(theta) * Z + np.sin(theta) * X

# -------------------------------------------------------------------------
# 3. Experimental Setup (Optimal Violation Angles)
# -------------------------------------------------------------------------
# Alice's settings (Standard basis and Rotated basis)
theta_A1 = 0 # 0 radians (Z-basis)
theta_A2 = np.pi / 2 # 90 degrees (X-basis)

# Bob's settings (Rotated by 45 degrees relative to Alice)
theta_B1 = np.pi / 4 # 45 degrees
theta_B2 = -np.pi / 4 # -45 degrees

# -------------------------------------------------------------------------
# 4. Correlation Evaluation
# -------------------------------------------------------------------------
print(f"{'Correlation Term':<20} | {'Angle Diff (deg)':<18} | {'Expectation Value'}")
print("-" * 60)

# List of measurement pairs corresponding to the CHSH terms
# We calculate S = E(A1, B1) + E(A1, B2) + E(A2, B1) - E(A2, B2)
measurement_configs = [
("E(A1, B1)", theta_A1, theta_B1),
("E(A1, B2)", theta_A1, theta_B2),
("E(A2, B1)", theta_A2, theta_B1),
("E(A2, B2)", theta_A2, theta_B2)
]

expectations = []

for label, tA, tB in measurement_configs:
# Construct local operators
Op_A = measure_op(tA)
Op_B = measure_op(tB)

# Construct global operator via Kronecker product
Op_Global = np.kron(Op_A, Op_B)

# Calculate Expectation <psi | Op | psi>
E_val = np.vdot(psi, np.dot(Op_Global, psi)).real
expectations.append(E_val)

# Calculate relative angle for display
diff = np.degrees(tA - tB)
print(f"{label:<20} | {diff:<18.1f} | {E_val:.4f}")

# -------------------------------------------------------------------------
# 5. CHSH Parameter Calculation
# -------------------------------------------------------------------------
# S = E1 + E2 + E3 - E4
S = expectations[0] + expectations[1] + expectations[2] - expectations[3]

print("-" * 60)
print(f"Calculated S Parameter: {S:.4f}")
print(f"Classical Bound (Local): 2.0000")
print(f"Tsirelson Bound (Graph): {2 * np.sqrt(2):.4f}")

if __name__ == "__main__":
verify_chsh_violation()

Simulation Output

Correlation Term     | Angle Diff (deg)   | Expectation Value
------------------------------------------------------------
E(A1, B1) | -45.0 | 0.7071
E(A1, B2) | 45.0 | 0.7071
E(A2, B1) | 45.0 | 0.7071
E(A2, B2) | 135.0 | -0.7071
------------------------------------------------------------
Calculated S Parameter: 2.8284
Classical Bound (Local): 2.0000
Tsirelson Bound (Graph): 2.8284

The tabulated data indicates a calculated S-parameter of S2.8284S \approx 2.8284. This value strictly exceeds the classical bound of 2.00002.0000, confirming that the correlations cannot be explained by any local hidden variable theory constrained to the emergent bulk geometry. Furthermore, the value precisely saturates the Tsirelson bound, verifying that the correlation is constrained by the unitary geometry of the graph algebra (SU(2)SU(2)) rather than the spatial separation of the manifold.