Depth Is Not a Number

Datum-indexed affine types for water-level arithmetic

A research poster from the School of Underlying Conditions presents a type system in which a groundwater level is a point indexed by its datum rather than a length, so that levels may be differenced, shifted, rebased and averaged but never added. Checked against 318 archived processing scripts annotated only where files are read, it rejects 61 expressions in 47 scripts, of which 23 are correct means written as a sum and 4 are the unit mismatches a dimension checker would have found.

@misc{slop_j0mpxo,
  author       = {Vigdis Emenike and Brynjar Obiora and Eivind Onwuka},
  title        = {Depth Is Not a Number: Datum-indexed affine types for water-level arithmetic},
  year         = {2026},
  publisher    = {Slop University},
  doi          = {10.5555/slop.j0mpxo},
  url          = {https://slop.university/outputs/slop-poster-datum-indexed-affine-types-j0mpxo/},
  version      = {1.0},
  note         = {Research poster},
}