There is no consensus as to who invented zero. The general belief is that the number as we know it today originated in 9th century India. However, there are researchers who do not agree with this view. There are no questions on its widespread use during ancient times though.
The Babylonians had a mathematical system in place by the second millennium BC. A space between the numbers was used to express lack of positional value. In 300 BC, two slanted wedges were in place. By 700 BC, zero was expressed using three hooks instead of the wedges. However, the placeholder cannot be considered a real zero because it was always used in conjunction with other numerals. It was also never used at the end of numbers.
As stated, the idea of zero as an actual number and not placeholder took hold in India. By the 9th century, mathematical calculations were being done using zero. The Hindus used zero the same way as other numbers. The Indian scholar Pingala is one of the most notable users of the number.
The term for zero was the Sanskrit word sunya. Usage of blanks in counting can be traced back to the 4th century BC. Decimal based place value notation was developed by the Indian mathematician and astronomer Aryabhata.
The Jain text (458 AD) is the oldest written document to use zero. The Chaturbhuja Temple has a stone inscription depicting zero as a small circle. Located in Gwalior, it dates from 875 AD. There are also several documents with copper plates depicting small circles. These date from the 6th century. However, there are historians who have expressed doubt on their authenticity.
Blank spaces have been used since the 4th century BC. During this time, counting rods were employed for calculating decimals that involved blanks. The ancient Chinese used the word wuru for zero. The 0 symbol came into use sometime in the 8th century courtesy of Gautama Siddha. The oldest Chinese text with a zero is the Mathematical Treatise in Nine Sections by Ch’in Chu-shao dating from 1247. Zero was symbolized by a round figure.
In the Arab World
The concept of the zero was introduced to the Arabs c. 500 AD. In 825 AD, the Persian scientist al-Khwarizmi published a book explaining the concept of zero. The book combined Hindu and Greek knowledge. While this does not help in determining who invented zero, it is important because of the key concepts he explained. The Arabic numeral system would be introduced to the West in the 12th century via Latin versions of his book.
Greece and Rome
The Greeks were uncertain about the place of zero in relation to other numbers. Zero and its concept was often the subject of religious and philosophical discussions. By 130 AD, Ptolemy had begun using zero for their numeral system.
The symbol was a circle with an over bar. Unlike the one in Babylon, it could be used independently and not just a placeholder. For this reason, many historians point to this as the first instance of Old World usage of zero. But the placements were usually confined to fractional components of numbers. It was not an integral component of a number.
Byzantine versions of Ptolemy’s Syntaxis Mathematica depict the zero as the micron of Greece. Zero was utilized in Roman numerals around 525. However, it was in the form of the word nulla. “N” was the first symbol of zero.
In the Americas
Zero was used by the Maya civilization. It is a placeholder in their
Mesoamerican Long Count calendar. Numerous glyphs were used to denote zero. The oldest goes back to 36 BC. Some of the most ancient applications of zero have been found outside Maya territory. That is why researchers presume that the number predated the Maya civilization.
The consensus is that the number was first used by the Olmecs. A lot of Long Count dates have been found in Olmec territory. Although zero became integral to the Maya, it had little effect on other numeral systems in the Old World.
Zero has numerous applications. It is used as a number and a year label. It is also a symbol and has plenty of applications in different mathematical branches. It is used as a symbol in physics and chemistry. It is also found in computer science. In many countries, dialing zero on phones is the number of operator assistance.
DVDs that are playable in all regions are labeled region 0. Roulette wheels usually have a 0 too. In many place value systems, it is employed as a placeholder. Sometimes it is called nought, naught or nil. The number is given to one of the members of an F1 team if the reigning champion the previous year is no longer in the sport.
The question of who invented zero may never be settled. However, there is no questioning its importance and relevance.