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.
1. 1  Chemistry. the use of litmus paper or solution to test the acidity or alkalinity of a solution. 2  a crucial and revealing test in which there is one decisive factor. 3  a test to establish the acidity or alkalinity of a mixture.  a critical indication of future success or failure.