几个月前的一天,正在读一本电子版的“宝书”。突然收到提示到楼下取包裹。打开后,大惊,竟然是来自加州女儿的礼物,纸版的同一本“宝书”。“撞车”了,哈。
前天,将这本珍贵的宝书,转送给了多伦多的一位小朋友:
今天,读到了宝书的最后一章,关于 Cantor 的贡献。很高兴曾去过他出生和童年的地方俄罗斯的圣彼得堡。读着读着,突然一闪念,既然 √2 是无理数,那么那些数字的随机性怎样呢?
马上搜一下,不得了,居然是个让数学家汗颜的尚未证明的问题。
https://www2.lbl.gov/Science-Articles/Archive/pi-random.html
In fact, not a single naturally occurring math constant has been proved normal in even one number base, to the chagrin of mathematicians. While many constants are believed to be normal -- including pi, the square root of 2, and the natural logarithm of 2, often written "log(2)" -- there are no proofs.