translation.en: Richard Feynman compared the accuracy of quantum theories -- experimental predictions -- to specifying the width of North America to within one hair's breadth of accuracy.
translation.zh: 理查德.费曼曾经这样描述量子理论的精确性 —基于实验预测—量子理论的精确性就如同使用一根头发丝去 厘定整个北美洲的宽度。