Condensate: an interactive simulator of two-dimensional quantum fluids

Abstract

Condensate is an interactive simulator of two-dimensional quantum fluids that runs in a web browser on phones, tablets and computers, with no installation. It solves eight models built on the Gross-Pitaevskii equation: a `vanilla' condensate, a dipolar gas with tilted dipoles, a binary mixture with quantum droplets, Rabi and spin--orbit coupled gases, a self-gravitating (Schrödinger-Poisson) condensate, a driven-dissipative polariton fluid, a rotating condensate and a finite-temperature stochastic projected Gross--Pitaevskii equation. A split-step Fourier solver runs on the graphics processor through WebGPU at up to $1024^2$ grid points, with a double-precision CPU engine as a fallback and reference. Users stir the fluid with a laser-like beam, imprint quantised vortices and change parameters while the fluid evolves. Each model comes with a ``Learn'' panel written for graduate students, giving the equations, core physics, and activities that pair an analytic prediction with an experiment in the app, and references keyed to a standard textbook. The whole application is one self-contained HTML file. In this accompanying text, we describe the models, the numerical method and the teaching material.