Zero

Zero is a number that is not exactly nothing but the absence of something. Nothing is an empty set which has zero elements within. On the number line, zero separates positive and negative numbers, and extends natural or counting numbers into a set of integers, critical to mathematics. Zero is also important in the decimal numbering system for multiplication and factor placeholders, and in binary for representing one of two states.

History
In the seventh century, Indian mathematician Brahmagupta wrote: “When zero is added to a number or subtracted from a number, the number remains unchanged; and a number multiplied by zero becomes zero.” Brahmagupta’s text Brahmasphutasiddhanta, written in AD628, was the first written description of zero as a number.

In AD773 Mohammed ibn-Musa al-Khowarizmi took Indian arithmetic and showed how the zero could function in algebraic equations, and by the ninth century the zero had entered the Arabic numeral system in an oval shape.

Eventually the use of zero as a mathematical function became increasingly widespread, was employed in graphing in the 17th century, and spawned calculus which was a whole new field of mathematics that depended on zero. This was the foundation on which physics, engineering, astronomy, computers, financial and economic theory developed.

Impact
The uses of zero have gone well beyond simple mathematics. Computers use binary code, the system on which the principle of two possible states exist, “on” and “off”. The ‘on’ state is assigned the value ‘1’, while the ‘off’ state is assigned the value ‘0’ - that is, zero. Without zero, modern electronics wouldn’t exist. Without zero, there’s no calculus, which means no modern engineering or automation. Without zero, much of our modern world literally falls apart.

Understanding how and why the great inventions were made that made modern science and technology possible, concerns all mankind. And the invention of zero certainly ranks among the greatest.