QED as the tensionless limit of the spinning string with contact interaction

Understand

We outline how QED with spinor matter can be described by the tensionless limit of spinning strings with contact interactions.

• The strings represent electric lines of force with charges at their ends.
• The contact interaction is constructed from a delta-function on the world-sheet which, although off-shell, decouples from the world-sheet metric.
• Integrating out the string degrees of freedom with fixed boundary generates the super-Wilson loop that couples spinor matter to electromagnetism in the world-line formalism.