Although Italian by birth, maritime explorer Christopher Columbus sailed across the Atlantic Ocean and discovered the Americas under the Spanish emperorâs name. During his first voyage, he led three Spanish galleons, the NiÃ±a, Pinta, and the Santa Maria.
Instead of the general notion that a void is a region of space with a low cosmic mean density; a hole in the distribution of galaxies, it defines voids to be regions in which matter is escaping; which corresponds to the Dark Energy equation of state, w.
Porosity or void fraction is a measure of the void (i.e., empty) spaces in a material, and is a fraction of the volume of voids over the total volume, between 0 and 1, or as a percentage between 0 and 100%. There are many ways to test porosity in a substance or part, such as industrial CT scanning.