Quantum Circuit Reasoning Models: A Variational Framework for Differentiable Logical Inference
Andrew Kiruluta
TL;DR
Quantum Circuit Reasoning Models (QCRM) recast logical inference as unitary evolution in a Hilbert space, encoding propositions as qubits and rules as entangling unitaries with phase penalties to enforce consistency. The framework combines variational optimization with a modular Quantum Reasoning Layer (QRL) consisting of Entangling Rule, Phase Penalty, and Mixing sublayers, enabling differentiable training and multi-hop reasoning. By simulating on classical hardware and outlining future directions for noise modeling, Hamiltonian-rule templates, and perception-to-reasoning transfer, the work outlines a path toward physically interpretable, reversible, interference-driven reasoning that can complement symbolic and neural approaches. The proposed architecture targets chemical inference, clinical decision support, and symbolic benchmarks, offering a principled quantum-algebraic alternative to address coherence, causality, and compositional reasoning in AI systems.
Abstract
This report introduces a novel class of reasoning architectures, termed Quantum Circuit Reasoning Models (QCRM), which extend the concept of Variational Quantum Circuits (VQC) from energy minimization and classification tasks to structured logical inference and reasoning. We posit that fundamental quantum mechanical operations, superposition, entanglement, interference, and measurement, naturally map to essential reasoning primitives such as hypothesis branching, constraint propagation, consistency enforcement, and decision making. The resulting framework combines quantum-inspired computation with differentiable optimization, enabling reasoning to emerge as a process of amplitude evolution and interference-driven selection of self-consistent states. We develop the mathematical foundation of QCRM, define its parameterized circuit architecture, and show how logical rules can be encoded as unitary transformations over proposition-qubit states. We further formalize a training objective grounded in classical gradient descent over circuit parameters and discuss simulation-based implementations on classical hardware. Finally, we propose the Quantum Reasoning Layer (QRL) as a differentiable hybrid component for composable reasoning models applicable to scientific, biomedical, and chemical inference domains.
