a vacuum
it is called white space and should be 20-30% in a page
Radiation.
The transfer of heat energy through empty space is called radiation.
The empty space in a container is referred to as "void space" or "headspace". It is the area within a container that is not filled with the product.
A region empty of matter is called a vacuum. It is a space devoid of particles, atoms, and molecules.
"radiation"
Conduction
Venus
vacuum
Radiation.
A mold fossil is formed when an organism dissolves and leaves an empty space in a rock. This empty space can later be filled by other minerals, forming a cast fossil.
That is called "Negative Space", and it's just as important to the layout of a drawing as any positive (drawn) space.