Mathematicians Of The Day

23rd May

On this day in 1576, Tycho Brahe was given use of the island of Hven (now Ven in Sweden) for his astronomical observatory. He built two observatories: Uraniborg and Stjerneborg.

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Quotation of the day

From Augustin-Louis Cauchy
√-1 we can repudiate completely and which we can abandon without regret because one does not know what this pretended sign signifies nor what sense one ought to attribute to it.
Writing in 1847 in regard to the square root of negative one.