其他2013spacex.com
Hyperloop Alpha 白皮书
Hyperloop Alpha
入门 · 约 60 分钟读完前置知识：基础物理常识、交通工程概念
导读
这是马斯克发布的 Hyperloop 概念论文，提出在洛杉矶与旧金山之间建造一种由低压管道和悬浮舱组成的超高速交通系统，宣称全程约 35 分钟、成本远低于加州高铁。论文详细讨论了管道支撑、舱体设计、太阳能供电等工程方案，并主张绕开人口密集区以降低征地成本。
HN 关注点：其成本估算是否现实，尤其是与加州高铁的对比以及站点选址远离市中心带来的实际可达性问题。
HN 评论精选
这几条评论里：质疑 1 补充 2 亲历 1
质疑Hyperloop 的低成本很大程度上靠绕开人口中心实现，站点远离市中心削弱了实际便利性
马斯克能宣称 Hyperloop 比高铁便宜，选址是关键原因。论文自己也指出征地成本极高，绕开主要人口中心是规避征收权和昂贵隧道的捷径。加州高铁受 1A 号提案约束必须经过多个城市中心并设约二十几个站，而 Hyperloop 提议绕过整个旧金山半岛、圣何塞以及弗雷斯诺、贝克斯菲尔德等中央谷地城市——高铁之所以在政治上可行，正是因为纳入了这些地区。此外 Hyperloop 的站点似乎远离市中心：'旧金山'站位于东湾，'洛杉矶'站更靠近伯班克。从城市规划角度看，这意味着多数乘客仍需短途接驳或开车，门到门总耗时反而更长。我不是说 Hyperloop 本身有缺陷，只是马斯克把问题过度简化了。
blackjack48查看英文原文
Location is a primary reason why Musk can claim Hyperloop will be cheaper than high speed rail. As the paper correctly points out, right-of-way acquisition is very expensive. Bypassing major population centers is an easy way out of using eminent domain or expensive tunneling to build the system. The HSR project is required by Proposition 1A to pass through several population centers in the state and have a couple dozen stops. Notably, Hyperloop proposes to bypass all of the SF peninsula, San Jose, and Central Valley cities like Fresno and Bakersfield. HSR was politically viable because these regions were included in the project. Furthermore, the route and station map appears to hint that Hyperloop's stations are positioned away from city centers. For example, the "San Francisco" station appears to be located in the East Bay and the "Los Angeles" station is closer to Burbank. This is quite significant from an urban planning perspective as it means that short haul transit or car trips have to be accommodated for a majority of those people who want to use the system. It also adds to the total travel time needed to get from door to door for a greater number of people than does HSR. I'm not saying that Hyperloop is an inherently flawed project or that HSR is the perfect solution to the state's long-haul transportation needs. I just think that Musk is oversimplifying the situation.
补充成本大头是支撑管道的混凝土支柱，约占总造价五分之二
有趣的是，成本中最大的单项既不是管道、舱体、真空泵、太阳能板，也不是土地，而是支撑管道的混凝土支柱——约占总成本五分之二。支柱计划每 30 米一个，共约 25000 个。
alex-g查看英文原文
It's interesting that the biggest line item in the costing is not the tube, nor the capsules, nor the vacuum pumps, nor the solar panels, nor the land, but the concrete pylons that support the tube - about two-fifths of the total. The pylons are planned to be 30m apart, making for about 25000 of them.
亲历35 分钟的行程不需要厕所，对厕所的担忧被夸大了
大家对厕所的关注让我困惑。我坐过没有卫生设施、连续几小时不停站的巴士。这只是 35 分钟、活动受限的行程，如果实在担心憋不住，还有其他效率较低的交通方式可选。
orofino查看英文原文
The focus from people on bathrooms is puzzling to me. I've been on buses, without facilities, that go for hours without stopping. This is a 35 minute ride with restricted movement, if you greatly fear being able to hold it for that long, there are other, less efficient methods of transport to accommodate you.
补充期待日本、韩国或中国这样有意愿的国家来推进 Hyperloop
如果美国不接手这个项目，我希望其他对大型公共交通项目有强烈兴趣的国家来做，比如日本、韩国和中国。
resu查看英文原文
If the U.S. doesn't take this on, I hope another country with a big appetite for enormous public transit projects takes this on. Japan, Korea, and China, I'm looking at you...
相关资源
从这篇论文所有 HN 讨论帖的全部评论里整理出来的链接。
历次讨论
- 2013Hacker News 讨论帖513 分 · 193 评
同领域还值得读
每个好的系统调节器都必须是该系统的一个模型 (1970)
Every Good Regulator of a System Must Be a Model of That System (1970)
这是控制论经典论文（Conant 与 Ashby，1970）：它试图论证，任何“好的”调节器都必须是其所调节系统的模型——即调节器与被控系统之间必须存在同构或模型关系。
其他2018 · 202 分 · 59 评进阶 · 约 45 分钟编辑精选复杂系统如何失效
How complex systems fail (2002)
总结了复杂系统如何失败的若干条经验法则：系统总是在多重故障的边缘运行，事故是多重因素叠加的结果，操作者实际上同时承担着维持生产与防范故障的双重角色，而事后归因往往把事故简化为某个…
其他2017 · 154 分 · 19 评入门 · 约 30 分钟编辑精选如何阅读论文
How to Read a Paper (2016)
介绍如何高效阅读学术论文，提出“三遍阅读法”：先快速浏览摘要、结论和图表把握概览，再理解主要内容，最后深入细节。
其他2017 · 715 分 · 80 评入门 · 约 10 分钟公元 1021 年欧洲人已在美洲存在的证据
Evidence for European presence in the Americas in AD 1021
这篇 Nature 论文用树木年轮定年，并结合公元 993 年宇宙射线事件标记，把纽芬兰 L'Anse aux Meadows 的 Norse 活动精确到公元 1021 年，为欧…
其他2021 · 655 分 · 391 评进阶 · 约 45 分钟一次通古斯级空爆摧毁了约旦河谷青铜时代城市 Tall el-Hammam
A Tunguska size burst destroyed Tall el-Hammam, Bronze Age city in Jordan Valley
研究约旦河谷青铜时代城市 Tall el-Hammam 被毁的原因。
其他2021 · 653 分 · 342 评入门 · 约 45 分钟