Khayām ,born on May,18, 1048 in Nichapur in Persia (present-day Iran) died on December,4, 1131, he is a renowned Persian scholar and writer.
In 1074, he was invited by the Seljuk Sultan Mālikshāh Jalāl al-Dīn to Isfahan to undertake the reform of the solar calendar which will last 5 years and organized astronomical observations. Director of the Observatory, he built astronomical tables known as Zidj-e Malikshahi and introduced, in the manner of the Julian calendar, a leap year and measured the length of the year as being 365,242 198,581 56 days.
After the death of Mālikshāh, he falls into disgrace, this should be the possible cause of some of his unorthodox poems . To cut short all suspicion, he undertakes a pilgrimage to Mecca. He lived later in Merv, the capital of the Seljuks empire and ended his days at Nishapur.
Omar Khayyâm is considered as"one of the great mathematicians of the Middle Ages" but his algebraic works were known in Europe only in the nineteenth century.
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Two important treatises in the history of mathematics: a classification written in 1070 in Samarcande about the equations of degree three with their positive roots and in his second treatise written in 1077 in Isfahan, he wrote a reflection on the axiom of the parallels .
Khayyam is also a poet and philosopher, his poems are called "rubaiyat", which means "quatrains". Khayyam's quatrains, often cited in the West for their skepticism, would, according to Idries Shah, contain "mystical pearls", making Khayyam a Sufi. He would have preached God's intoxication, and said he was unfaithful but believing. Beyond the first hedonistic degree, quatrains would therefore have a mystical dimension according to this commentator.
It presents without order and without method, to use an expression of Montaigne in the preface of the Essais - thus without a strategy to convince - his hopes, doubts and discouragements in what seems an effort of human truth. This is perhaps one of the reasons for the worldwide success of his quatrains.