World's Roundest Object!
6 人推荐 · 跨 4 个月 · 2013–2018
中文导读
Veritasium 详解千克重新定义的前因后果：从依赖物理原器铂铱合金千克原器，到借助阿伏伽德罗计划打磨出的几乎完美的高纯度单晶硅球，并顺带聊了聊这个单位名称背后的冷历史。
为什么 HN 推它
深入浅出科普普朗克常数与阿伏伽德罗方案的绝佳入门短片，直观易懂。
「这个视频绝对不容错过。」HN 网友原话：this video is an imperative watch
英文原摘要（HackerTube / Claude 整理）
Veritasium explains the effort to redefine the kilogram, which was still defined by a physical artifact, and how a near-perfect silicon sphere from the Avogadro project helps. It also covers the history of the unit's odd naming.
Recommended in kilogram-redefinition threads as a clear, short explainer of the Avogadro and Planck approaches.
HN 上的提及
there's a nice video on this
this video is an imperative watch
it is also very interesting in it's own right.
Fantastic video by Vertiasium on this