Experimental Resolution of Temporal Paradoxes and Retrocausal Loops on NISQ Superconducting Hardware: A Comprehensive Study on Deutsch's Consistency Condition
محمد عيسى
Published: 2026/07/30 · PUB-2026-000047
Abstract
The physical realization of Closed Timelike Curves (CTCs) and temporal paradoxes remains a central challenge at the intersection of general relativity and quantum mechanics. While classical general relativity admits solutions with closed causal loops that induce logical inconsistencies (e.g., the Grandfather Paradox), quantum mechanical formulations—most notably Deutsch's self-consistency model—predict that quantum interference and state mixedness eliminate temporal inconsistencies. Here, we present a comprehensive experimental implementation and empirical validation of quantum retrocausal loops and paradox resolutions executed on Noisy Intermediate-Scale Quantum (NISQ) superconducting processors. Utilizing IBM Quantum hardware (ibm_kingston and ibm_fez), we implement two distinct protocols: a four-qubit discrete-time quantum walk simulation incorporating retrocausal feedback via conditional phase alignments, and a two-qubit logical representation of the Grandfather Paradox. Our empirical results validate Deutsch's theoretical fixed-point condition: the four-qubit retrocausal loop converges to an equitable mixed-state distribution (≈ 25%) on ibm_kingston (measured counts: |00⟩:268, |10⟩:265, |01⟩:254, |11⟩:213), while the Grandfather Paradox circuit settles into a stable maximal superposition (≈50/50) on ibm_fez (|11⟩:484, |00⟩:485, |10⟩:18, |01⟩:13). The results demonstrate high temporal fidelity under hardware noise and provide empirical evidence that physical quantum processors natively resolve causal paradoxes.
Keywords: Temporal Paradoxes، Retrocausal Loops، NISQ Hardware، Superconducting Qubits، Deutsch's Consistency Condition، Quantum Computing، Closed Timelike Curves، Grandfather Paradox