Aryabhata

Aryabhata ( ISO: ) or Aryabhata I (476–550 CE) was an Indian mathematician and astronomer of the classical age of Indian mathematics and Indian astronomy. He flourished in the Gupta Era and produced works such as the '' Aryabhatiya'' (which mentions that in 3600 ''Kali Yuga'', 499 CE, he was 23 years old) and the ''Arya-siddhanta.''

Aryabhata created a system of phonemic number notation in which numbers were represented by consonant-vowel monosyllables. Later commentators such as Brahmagupta divide his work into ''Ganita ("Mathematics"), Kalakriya ("Calculations on Time") and Golapada ("Spherical Astronomy")''. His pure mathematics discusses topics such as determination of square and cube roots, geometrical figures with their properties and mensuration, arithmetric progression problems on the shadow of the gnomon, quadratic equations, linear and indeterminate equations. Aryabhata calculated the value of pi (''π)'' to the fourth decimal digit and was likely aware that pi (''π)'' is an irrational number, around 1300 years before Lambert proved the same. Aryabhata's sine table and his work on trignometry were extremely influential on the Islamic Golden Age; his works were translated into Arabic and influenced Al-Khwarizmi and Al-Zarqali. In his spherical astronomy, he applied plane trigonometry to spherical geometry and gave calculations on solar, lunar eclipses. He discovered that the apparent westward motion of stars is due to the spherical Earth's rotation about its own axis. Aryabhata also noted that the luminosity of the Moon and other planets is due to reflected sunlight.

Biography

Name

While there is a tendency to misspell his name as "Aryabhatta" by analogy with other names having the " bhatta" suffix, his name is properly spelled Aryabhata: every astronomical text spells his name thus, including Brahmagupta's references to him "in more than a hundred places by name". Furthermore, in most instances "Aryabhatta" would not fit the metre either.

Time and place of birth

Aryabhata mentions in the ''Aryabhatiya'' that he was 23 years old 3,600 years into the ''Kali Yuga'', but this is not to mean that the text was composed at that time. This mentioned year corresponds to 499 CE, and implies that he was born in 476. Aryabhata called himself a native of Kusumapura or Pataliputra (present day Patna, Bihar).

Other hypothesis

Bhāskara I describes Aryabhata as ''āśmakīya'', "one belonging to the ''Aśmaka'' country." During the Buddha's time, a branch of the Aśmaka people settled in the region between the Narmada and Godavari rivers in central India.

It has been claimed that the ''aśmaka'' (Sanskrit for "stone") where Aryabhata originated may be the present day Kodungallur which was the historical capital city of ''Thiruvanchikkulam'' of ancient Kerala. This is based on the belief that Koṭuṅṅallūr was earlier known as Koṭum-Kal-l-ūr ("city of hard stones"); however, old records show that the city was actually Koṭum-kol-ūr ("city of strict governance"). Similarly, the fact that several commentaries on the Aryabhatiya have come from Kerala has been used to suggest that it was Aryabhata's main place of life and activity; however, many commentaries have come from outside Kerala, and the Aryasiddhanta was completely unknown in Kerala. K. Chandra Hari has argued for the Kerala hypothesis on the basis of astronomical evidence.

Aryabhata mentions "Lanka" on several occasions in the ''Aryabhatiya'', but his "Lanka" is an abstraction, standing for a point on the equator at the same longitude as his Ujjayini.

Education

It is fairly certain that, at some point, he went to Kusumapura for advanced studies and lived there for some time. Both Hindu and Buddhist tradition, as well as Bhāskara I (CE 629), identify Kusumapura as Pāṭaliputra, modern Patna. A verse mentions that Aryabhata was the head of an institution (') at Kusumapura, and, because the university of Nalanda