An isoperimetric profile gives the least possible perimeter of a set with a prescribed volume.
For an open set , its relative isoperimetric profile is
where
is relative perimeter and
is Lebesgue measure.
For the unit cube , Deng et al. (2026) reported
where
and
.
Up to isometries of the cube,
complementation, and changes on sets of measure
zero, the minimizers are corner eighth-balls, edge
quarter-cylinders, and coordinate slabs. The transitions
occur at
and
,
with both adjacent types minimizing at each transition (Deng et al. 2026).
Deng et al. (2026) report mathematical assistance from ChatGPT with proof strategies and calculations.