Demos & Tutorials

End-to-end examples that show Tesseracts in action — from optimization workflows to data assimilation.

Tip

For more community-contributed examples, check out the Tesseract Showcase on the forum.

Data assimilation demo

A complete 4D-Variational data assimilation scheme for a chaotic dynamical system, built with differentiable Tesseracts.

4D-Var Data Assimilation

Full walkthrough of a 4D-Var scheme using a differentiable Lorenz-96 Tesseract — from building the Tesseract to running the optimization loop.

4D-Variational Data Assimilation for a Chaotic Dynamical System
Lorenz Tesseract

Detailed implementation of the JAX-based Lorenz-96 solver Tesseract used in the 4D-Var demo.

Building the JAX Solver Tesseract for Lorenz-96
Bayesian Inference

Use the same Lorenz-96 Tesseract as the forward model inside a NumPyro probabilistic workflow — recover the posterior over an unknown forcing parameter with gradient-based MCMC.

Simulator-in-the-Loop Bayesian Inference with Tesseract

Simulation & design optimization demos

End-to-end differentiable optimization through physics simulators, composing Tesseracts with JAX or PyTorch code via Tesseract-JAX and Tesseract-Torch.

CFD Flow Optimization

Optimize the initial velocity field of a 2D Navier-Stokes simulation so its vorticity evolves into a target image — gradient-based optimization through a JAX-CFD Tesseract.

Gradient-Based Optimization of Fluid Flows
FEM Shape Optimization

Compose a geometry Tesseract (PyVista, finite-difference gradients) with a FEM Tesseract (jax-fem) to optimize structural bar configurations for minimum compliance.

Parametric Shape Optimization with Differentiable FEM Simulation
Multi-Physics Optimization

Couple two independently built thermal and structural Tesseracts with two-way thermoelastic feedback, and differentiate through the resulting equilibrium to solve an inverse-design problem — with constant-memory gradients via implicit differentiation.

Multi-Physics Pipeline with End-to-End Gradient Optimization
Differentiable Fortran (Enzyme)

Solve two inverse heat-transfer problems by differentiating a Fortran solver end-to-end: Enzyme generates exact derivatives at the LLVM IR level, and jax.value_and_grad drives the optimization through Tesseract-JAX.

Inverse Heat Transfer with Automatic Differentiation
Learned Closure (PyTorch)

Train a native PyTorch neural viscosity closure end-to-end through a containerized Burgers’ equation solver Tesseract used as a differentiable layer. Gradients flow from the loss through the solver’s VJP, over HTTP, into the network using Tesseract-Torch.

Learned Closure: Training a Neural Viscosity Model Through a PDE Solver (PyTorch)

Optimization tutorials

These tutorials walk through complete optimization workflows using Tesseracts with different autodiff frameworks:

JAX Rosenbrock Minimization

End-to-end function minimization using JAX autodiff with Tesseract-JAX.

https://si-tesseract.discourse.group/t/jax-based-rosenbrock-function-minimization/48
PyTorch Rosenbrock Minimization

End-to-end function minimization using PyTorch autodiff.

https://si-tesseract.discourse.group/t/pytorch-based-rosenbrock-function-minimization/44
JAX RBF Fitting

Gaussian radial basis function fitting with JAX automatic differentiation.

https://si-tesseract.discourse.group/t/jax-auto-diff-templates-gaussian-radial-basis-function-fitting/51