"Less than a century ago it was realised that stars are still forming in our Galaxy today. Over the decades since, the questions of what physical processes dominate the star formation process and how the statistical properties of stars are determined have been some of the key questions in astrophysics. Recently, I have advanced numerical simulations of star formation to the point that, for the first time, we can reproduce a wide range of the observed statistical properties of stars and brown dwarfs.Here I propose an ambitious project that will make a step change in star formation theory and produce a truly predictive theory of star formation, as opposed to the past state of the field where we have been constantly searching for a mixture of initial conditions and physical processes that can reproduce the stellar properties that we observe. The project will involve substantial numerical code development, culminating in a fluid dynamical code that incorporates all of the major physical processes thought to influence star formation, including radiative transfer, non-ideal magnetohydrodynamics, dust, and chemistry. The scientific outputs will be the determination of how each physical process affects the star formation process, and a wide range of predictions of how stellar properties should vary in different environments and with different initial conditions. These predictions will give direction to, and be tested by, the next generation of observational surveys of star-forming regions and stellar systems, while at the same time may be employed to improve our understanding of how star formation affects galaxy formation and evolution and how the variation in stellar properties impacts the diversity of planetary systems."