A finite universeâthat is, a universe of limited sizeâeven one with trillions and trillions of stars, just wouldn't have enough stars to light up all of space. Although the idea of a finite universe explains why Earth's sky is dark at night, other causes work to make it even darker.Not only is the universe finite in size, it is also finite in age.lthough the idea of a finite universe explains why Earth's sky is dark at night, other causes work to make it even darker. Not only is the universe finite in size, it is also finite in age.
Noun. 1. litmus-a coloring material (obtained from lichens) that turns red in acid solutions and blue in alkaline solutions; used as a very rough acid-base indicator. litmus test. acid-base indicator-an indicator that changes color on going from acidic to basic solutions.
a: a substance (as litmus) used to show visually (as by change of color) the condition of a solution with respect to the presence of a particular material (as a free acid or alkali) b: tracer 4b. 3.