# Modeling

TODO: Describe model parameter conventions and units.

## Parameters
- epsilon: relative permittivity (dimensionless).
- sigma: electrical conductivity (S/m).
- mu: relative permeability (dimensionless).

## Units and Scaling
TODO: Specify expected units for dx/dy/dt and any scaling rules.

## Grid and Shapes
TODO: Document tensor shapes (ny, nx) and batching conventions.

## Constraints and Masks
TODO: Describe common constraints (air layer masks, bounds).
