The law is Boyel's law.
One of the primary laws of material science that impacts the submerged jumping condition for scuba jumpers is Boyle's law.
The law states that as weight changes, the volume of gases in a jumper's body pits and adaptable gear changes as well. Where the water weight builds, 'air spaces' reduces in size, yet as water weight diminishes, the 'air spaces' increments in size. Where the two changes are in direct extent to the weight increment or lessening, the temperature is held consistent.