游戏/互动 Game / interactive 工具页 Tool
Relativity Park：光速降到步行时的狭义相对论 Relativity Park: special relativity when light walks
把光速降到步行，在公园里看见相对论。 Set the speed of light to a walking pace and watch relativity in a park.
详细介绍Details
Dmitry Brant 的公开互动演示：把光速压到 5 km/h（约步行速度），在公园视角里用 WASD 加速，观察洛伦兹收缩、光行差、多普勒变色与相对论光束效应，各效应可单独开关。Show HN 当日上过热榜；纯前端可打开，无需登录。 Dmitry Brant’s public interactive demo: the speed of light is set to 5 km/h (a brisk walk); accelerate with WASD through a park and watch length contraction, aberration, Doppler colour shift, and relativistic beaming, each toggleable. Hit the Show HN front page the same day; pure front-end, no login.
适合学什么What to learn
- 游戏/互动 Game / interactive
可直接玩或操作的教学游戏与 WebGL 演示。 Teaching games and WebGL demos you can play in the browser.
- 工具页 Tool
在浏览器里生成 CSS/HTML 的小工具。 In-browser tools that generate CSS or HTML.
为什么推荐Why we recommend it 演示公开可打开；物理教学用途，非论文复现。预览来自现场截图（无 og:image）。 Demo is publicly open; physics-teaching demo, not a paper reproduction.
核验记录：来源、抓取与截图说明Verification log: sources, checks, and captures
HN item 49637385（Show HN: What if the speed of light was 5 km/h?）。 （item 49637385）HN item 49637385 (Show HN: What if the speed of light was 5 km/h?). Preview is a live screenshot (site has no og:image). (item 49637385)
