Utilizing Monte Carlo Methods and Shifting to Preserve Causality in Particle Simulations

This thesis investigates the use of parton shifting technique facilitated by Monte Carlo methods to preserve causality in relativistic particle simulations, focusing on parton cascade models used in high-energy nuclear collisions. In such simulations, relativistic effects can lead to frame-dependent collision ordering, resulting in causality violations. To address this issue, a parton shifting method is implemented in which colliding partons are relocated to a common interaction point in their center-of-momentum frame. This ensures that collision sequences remain consistent across different reference frames. The results demonstrate that parton shifting successfully removes frame-dependent inconsistencies and preserves causal ordering, improving the physical reliability of relativistic transport simulations.