|Born: about 1690 in Amber (now Jaipur), India
Died: about 1750 in India Jagannatha had Jai Singh Sawai as his
patron. Jai Singh Sawai was the ruler of Amber, now Jaipur, in
eastern Rajasthan. He began his rule in 1699 and by clever use of tax
rights on land that was rented by the state to an individual person
he became the most important ruler in the region. His financial
success let him finance the scholarly works of people such as
Jagannatha. It is worth noting that Jai Singh's importance was
recognised by Amber which was then called Jaipur in his honour.
Jai Singh ruled Amber throughout the period in which Jagannatha was
producing his scientific work. He realised that the health of the
country required Indian culture and science to be revitalised and
returned to its position of leading importance which it had
possessed. So Jai Singh employed Jagannatha to make Sanskrit
translations of the important Greek scientific works which at that
time were only available in Arabic translations.
translated Euclid's Elements from the Arabic translation by Nasir
al-Din al-Tusi made nearly 500 years earlier. His Sanskrit version
was called Rekhaganita and it was completed by 1727. We know this
date since a copy was made by a scribe and he dated the start of his
work as 1727.
Ptolemy's Almagest had been one of the works
which Arabic scientists had studied intently and, in 1247, al-Tusi
wrote Tahrir al-Majisti (Commentary on the Almagest) in which he
introduced various trigonometrical techniques to calculate tables of
sines. Jagannatha translated al-Tusi's Arabic version but he did more
than this for he included in the same work, which he called
Siddhantasamrat, his own comments on related work of other Arabic
mathematical astronomers such as Ulugh Beg and al-Kashi.
is clear from Jagannatha's work that he is working as one of a group
of mathematicians and astronomers gathered by Jai Singh in his scheme
to bring the best in scientific ideas from outside India to
reinvigorate the scientific scene in India.
In  Gupta
looks at the history of the result
sin(p/10) = (v5 - 1)/4
in Indian mathematics. The result appears for the first time in the
work of Bhaskara II, but there were a number of interesting proofs of
the result by later Indian mathematicians. One of the proofs
presented by Gupta in  was by Jagannatha who gave a proof which
was essentially geometric in nature but, interestingly, contained an
analytic procedure in terms of trigonometric and algebraic steps.
Article by: J J O'Connor and E F Robertson