Borrowing the mathematics of a swing
HamVision: Hamiltonian dynamics as inductive bias for medical image analysisMedical Image Analysis, 2026
Start here
Push a child on a swing and you are using one of the oldest equations in physics. The swing has a rhythm of its own, it stores the energy you give it and hands it back, and friction slowly settles it. Three hundred years of mathematics describe that behaviour exactly.
What we did
We built that swing into a neural network. Every image the model looks at has to pass through a narrow point in the middle of the network, and at that point we put a damped oscillator: a small piece of physics with position, momentum and energy. Instead of the model having to learn from nothing how information ought to move, it starts with a physical habit already in it.
What happened
It needs four times fewer parameters and seven times fewer arithmetic operations than the best previous model, and still leads or matches it on eight of nine medical imaging benchmarks, across nine different kinds of image. On skin lesions the margin is nearly 18 percentage points. On the smallest benchmark, 546 training images, it loses, which is what you would expect of a model that has structure to fill in.
Why it matters
A model this small can run on the hardware a hospital already owns, which is the difference between a result and a tool.
The part worth pausing on
The oscillator's energy map, which is just a picture of where the model is spending effort, settles on the part of the image that decides the diagnosis. Nobody told it where to look. It was never given a single outline to copy.