3月14日是圆周率日，竟然也是爱因斯坦的生日和霍金的忌日

March 14, 2018, is Pi Day — that’s pi, not pie — and on Wednesday, Google marks the 30th anniversary of the math-inspired holiday with a special Doodle.

2018年3月14日，是Pi Day--这是圆周率，而不是馅饼 - 在周三，谷歌用特别的Doodle标志来纪念该数学假期的第30周年。

Pi, denoted by the Greek letter “π”, has been part of human knowledge for millennia, but it wasn’t until 1988 that physicist Larry Shaw organized what is now recognized as the first “Pi Day” celebration at the San Francisco Exploratorium science museum. Shaw chose March 14, or 3.14 — the first three digits of pi — as Pi Day.

圆周率以希腊字母“π”表示，几千年来一直是人类知识的一部分，但直到1988年，物理学家Larry Shaw才第一次组织了在旧金山探索科学博物馆举行的“圆周率日”庆典。 Shaw选择了3月14日，即3.14 - 圆周率的前三位数字 - 作为圆周率日。

Pi represents the ratio of a circle’s circumference to its diameter. It’s an important part of the foundation of mathematics, most importantly geometry, where pi is key to equations calculating the area of a circle, A = πr2, and the volume of a cylinder, V = πr2h.

圆周率代表圆的周长与其直径的比值。它是数学基础的重要组成部分，特别是在几何学上，圆周率是计算圆的面积方程的关键，A =πr2，圆柱体积V =πr2h。

Pi is a mathematical constant, meaning it isn’t changed by the size of the numbers it’s used to equate, and it is irrational, meaning it has an infinite number of digits that never repeat.

圆周率是一个数学常数，意味着它不会被它等式中所用的数字大小所改变，而且它是非理性的，这意味着它有无限数量的数字而且不会重复。

The rise of computing technology has led to an arms race of sorts to calculate ever more digits of pi: the current record was set last year by Christian physicist Peter Trueb, calculated pi to 22.4 trillion digits — 22,459,157,718,361, to be exact — outpacing the previous record set in 2013 by 9 million digits.

计算技术的兴起导致了一场计算更多圆周率数字的军备竞赛：目前的纪录是由基督教物理学家Peter Trueb在去年设定的，计算出圆周率为22.4万亿位数 - 确切迪说是22,459,157,718,361 - 超过了之前2013年创纪录的900万位数字。

Pi Day was officially recognized by Congress in 2009, and it’s inspired quirky and pun-filled celebrations, including eating circular treats, from fruit pies to pizza, as well as dressing like Albert Einstein, whose birthday serendipitously falls on the math-imbued day.

圆周率日于2009年获得国会正式承认，它的灵感来自古怪且充满双重色彩的庆祝活动，包括吃圆形食物如水果派和比萨饼，或者穿得像阿尔伯特·爱因斯坦一样，因为他的生日偶然落在充满数学的这一天。