Branching Flows

Discrete, Continuous, and Manifold Flow Matching with Splits and Deletions.

Overview

Flow matching with stochastic splits and deletions.

Branching Flows augments a base Markov generator with split and deletion events. A forest of binary trees couples roots sampled from a simple initial distribution to leaves from the data distribution.

Along each branch, elements evolve according to the chosen base process. At split events an element is duplicated in place; at deletion events it is removed. The model learns the base generator together with the split and deletion rates.

Graphical abstract showing Branching Flows transporting variable-length states through splits and deletions.

QM9

Small molecules.

QM9 provides a benchmark for multimodal (continuous atom positions and discrete atom types) variable-length distribution learning.

QM9 molecule generation trajectories.
QM9 summary metrics.
Small-molecule trajectories and summary metrics from the QM9 setting. Note: metrics are from more (and newer) models than in the PDF. Multimodal FM is an architecture-matched "oracle length" Flow Matching baseline, and a number of Branching Flows (BF) variants are shown.

New results: Branching La Proteina

Branching Flows finetunes into La Proteina.

La Proteina (Geffner et al., 2025) uses a latent side chain representation for all-atom structure generation. Branching Flows finetunes retain exceptionally high designability. Examples below from a finetune of the LD3 variant.

La Proteina branching trajectory with multiple protein samples.
Generated La Proteina protein samples.

Resources

Paper, code, and model links.