Who discovered zero?

The concept of zero evolved over time and across different cultures, so its "discovery" isn't attributable to a single person. There are two key aspects to consider: zero as a placeholder and zero as a number.

• Zero as a Placeholder: The Babylonians, around 300 BCE, used a placeholder (like a space or a specific symbol) within their sexagesimal (base-60) number system to denote the absence of a unit in a particular place (e.g., to distinguish 36 from 306). The Mayans also independently developed a placeholder zero for their calendar system.
• Zero as a Number: The concept of zero as an actual number that could be used in calculations (addition, subtraction, multiplication, division) was developed in India.
• Brahmagupta (c. 598–668 CE): In his work Brahmasphutasiddhanta (628 CE), Brahmagupta was one of the first to explicitly define rules for arithmetic operations with zero (e.g., a + 0 = a; a - 0 = a; a × 0 = 0). He also discussed division by zero, though his understanding here was incomplete by modern standards.
• Earlier Roots in India: The use of a small circle symbol for zero and its integration into the decimal place-value system in India predates Brahmagupta, with inscriptions showing its use by the 7th century and evidence suggesting earlier development.
• Global Spread: The Indian concept of zero, along with the decimal number system, was later transmitted to the Arab world (notably by scholars like al-Khwarizmi) and then to Europe, revolutionizing mathematics.
• Key Takeaway: While placeholder zeros were used by Babylonians and Mayans, the crucial development of zero as a number, with defined arithmetic properties, originated in India, with Brahmagupta being a key figure in formalizing its use.