The Virgo Consortium

The SWIFT Code

Simulation setup test

A selection of simulation results obtained with the Swift code, illustrating the huge range of problems that have already been targeted and the flexibility of the solver.


SWIFT is a computer program designed for running on supercomputers that simulates forces upon matter due to two main things: gravity and hydrodynamics (forces that arise from fluids such as viscosity). The creation and evolution of stars and black holes is also modelled together with the effects they have on their surroundings. This turns out to be quite a complicated problem as we can’t build computers large enough to simulate everything down to the level of individual atoms. This implies that we need to re-think the equations that describe the matter components and how they interact with each other. In practice, we must solve the equations that describe these problems numerically, which requires a lot of computing power and fast computer code.

We use SWIFT to run simulations of astrophysical objects, such as planets, galaxies, or even the whole universe. We do this to test theories about what the universe is made of and how it evolved from the Big Bang up to the present day!


The paper for “The SWIFT code” has been submitted by Schaller et al. 2023. For more information and relevant publications please visit Leiden's description page or contact Matthieu Schaller.