Drift-Free Conservative Dynamics from Quantized Interaction Rules
This work provides a novel method for eliminating numerical drift in conservation law simulations, benefiting computational scientists in fluid dynamics and related fields.
The authors introduce an operator-level formulation for conservative dynamics using quantized state spaces and antisymmetric integer-transfer operators, achieving exact conservation without round-off drift. Numerical experiments demonstrate preservation of high-frequency transport and sharp discontinuities in Burgers dynamics.
Conservation laws are conventionally discretized through floating-point flux evaluation, with invariants obtained by cancellation of approximate interface contributions and admissible weak solutions selected by reconstruction and Riemann solvers. Here we introduce an operator-level formulation in which conservative dynamics is realized as an exact discrete interaction rule on a quantized state space. The update is defined by an antisymmetric integer-transfer operator, which enforces conservation exactly at the arithmetic level and eliminates round-off drift from the primitive evolution \cite{highamAccuracyStabilityNumerical2002}. For scalar laws, monotone order-preserving transfers select admissible shock structures within the primitive update, rather than through flux reconstruction. Numerical experiments show that the interaction rule preserves high-frequency transport near the Nyquist limit and maintains sharply localized discontinuities in Burgers dynamics. The same construction extends to multidimensional problems and systems of conservation laws through oriented, vector-valued integer transfers. These results indicate that conservative dynamics admits an exact discrete realization in which both invariance and entropy selection are encoded at the operator level, rather than arising from approximate flux cancellation.