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Who figured it out first — and who figured it out again, centuries later, somewhere else? Experli traces what each civilization contributed to mathematics and astronomy, down to the exact sentence in the primary source. Tier-rated, re-verified every night. The Indian tradition is live; more civilizations are coming.

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MathematicsT1

In 628 CE, Brahmagupta wrote the world's first explicit arithmetic of zero. Add zero, subtract zero, multiply by zero — he gave each operation a rule. He also wrote down a rule for dividing by zero. He got that one wrong, but he tried — and 'tried' is exactly the achievement: Western mathematics wouldn't treat zero as a number with its own arithmetic for another thousand years.

Algebra, with Arithmetic and Mensuration, from the Sanscrit of Brahmegupta and Bháscara · tr. H. T. Colebrooke, 1817

AstronomyT1

In 499 CE, Aryabhata wrote down a 7-word analogy that explains why we don't feel the Earth move: As a man in a boat going forward sees a stationary object moving backward. He said the stars appear to circle westward not because they move but because the Earth rotates eastward — 1,582,237,500 rotations per yuga. Copernicus published the heliocentric idea in 1543. Aryabhata published the rotation hypothesis 1,044 years earlier.

The Aryabhatiya of Aryabhata · tr. W. E. Clark, 1930

MathematicsT1

Divide three by zero. A modern calculator returns an error; Bhāskara II's Bījagaṇita (1150 CE) returns an answer: khahara, "termed an infinite quantity." He writes that this quantity is unaltered when anything finite is added to it or taken away — and compares it to the changeless deity in whom worlds are absorbed and re-created. Europe had no working symbol for infinity until Wallis introduced ∞ in 1655.

Algebra, with Arithmetic and Mensuration, from the Sanscrit of Brahmegupta and Bháscara · tr. H. T. Colebrooke, 1817

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Mathematics

Indian mathematics, 500 BCE–1200 CE. Pingala, Aryabhata, Brahmagupta, Mahāvīra, Bhāskara II.

29 verified claims

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Astronomy

Indian astronomy, 400 CE–1200 CE. Sūrya-Siddhānta, Aryabhata, Varāhamihira, Brahmagupta, Bhāskara II.

21 verified claims