The famous German-born theoretical physicist, developer of the general theory of relativity, Mr Albert Einstein would be celebrating his 134th birthday today, had he not died in 1955.
Coincidentally, Einstein`s birthday falls on Pi day. What the hell is that, you are wondering...
Basically, it is the celebration of "The number π is a mathematical constant that is the ratio of a circle's circumference to its diameter, and is approximately equal to 3.14159."
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No surprise that this concept is American! It is using their date format that the chosen day for celebrating Pi is 14 March - 3/14.
Across the States, especially at universities, they organize Pi and Einstein tributes, whereby in turn American fashion, they eat pie and dress up.