QuantumSuperposition and PositronicVariables

This paper presents QuantumSuperposition and PositronicVariables, two interlinked .NET libraries for modelling uncertainty, quantum-style superposition, and time-looped convergence in ordinary C# code.

QuantumSuperposition provides (1) a generic superposition engine in the form of QuBit<T> and Eigenstates<T> with complex amplitudes, arithmetic, LINQ integration and non-destructive sampling, and (2) a physicsflavoured quantum layer with multi-qubit QuantumSystem, entanglement management, gate catalogues, canonical states, and bundled implementations of the Quantum Fourier Transform (QFT) and Grover’s search algorithm.

PositronicVariables builds on the same superposition semantics to model reversible temporal logic: variables that can participate in feedback loops, roll their state backwards and forwards through hypothetical timelines, and converge to a consistent fixed point (or, in pathological cases, a politely documented paradox).

The resulting ecosystem lets .NET developers treat "maybe" and "many possible futures" as first-class values while still enjoying static typing, IDE autocompletion and the reassuring hum of the garbage collector. We describe the design and semantics of both layers, motivate their use as teaching and experimentation tools, and compare them to existing quantum SDKs and probabilistic programming languages.

Our guiding design principle is simple: make the multiverse feel like idiomatic C#, with just enough weirdness to be fun but not enough to summon an actual physicist.