# Techniques: Dagger categories and the complex numbers

## What the paper contributes (one paragraph)
An axiomatisation of the category of finite-dimensional Hilbert spaces and linear contractions.

## Techniques offered
- **Categorical axiomatisation** - axioms characterising the dagger category of Hilbert spaces.
  - guarantee: none.
  - quote: "axioms for the category of finite-dimensional Hilbert spaces"

## Where it could apply
- Target primitive(s): none
- Target application group(s): platforms_tooling
- Code family / hardware assumptions: none

## Caveats
Pure foundations; nothing directly suppliable.