Qsim

Qsim is the name of several software tools used in different domains. The most widely referenced is a quantum circuit simulator for quantum computing research. It models the evolution of quantum states under unitary gates and measurements, supporting state-vector representations for small to mid-sized circuits and density-matrix methods for mixed states. Many versions incorporate simple noise models to study imperfect devices and provide scripting interfaces or Python bindings for integration with broader quantum software stacks. Qsim is often developed by academic researchers or open-source communities and is distributed under permissive licenses to support experimentation and benchmarking.

In other contexts, Qsim denotes a discrete-event simulation tool used to model queuing networks, service systems, and logistics processes. This usage emphasizes event-driven modeling, allowing users to define entities, resources, and routing rules to evaluate performance metrics such as wait times and throughput. The software is used in operations research and industrial engineering and may include a graphical interface or API for building and running multiple scenarios.

Because the name Qsim appears across domains, users should verify the exact project or repository to understand its scope, license, and supported features. See also quantum simulation and discrete-event simulation.