物理与天文2021arxiv.org
黑洞周围的戴森球
A Dyson sphere around a black hole
进阶 · 约 60 分钟读完前置知识:黑洞物理基础、吸积盘与相对论喷流、戴森球概念
导读
这篇论文探讨围绕黑洞建造戴森球以获取能量的设想。作者分析了黑洞周围各种能量来源(如吸积盘、相对论喷流、霍金辐射、CMB 等)的可利用功率,指出吸积盘和喷流能提供大量能量,而霍金辐射和宇宙微波背景几乎可忽略。
HN 关注点:戴森球通常与恒星联系在一起,围绕黑洞这一非常规设想以及其作为潜在技术文明迹象的可探测性引发了 HN 读者的兴趣和讨论。
HN 评论精选
这几条评论里:质疑 2 补充 1 亲历 1
质疑质疑论文忽略了彭罗斯过程这一更可靠的黑洞能量提取方式
为什么他们不提从黑洞旋转中提取能量(彭罗斯过程或类似机制)?我以为那才是从黑洞获取能量最可靠的方式。
eterevsky查看英文原文
Why aren't they mentioning extracting energy from black hole rotation (Penrose process [1] or something similar)? I thought it was the most reliable way of extracting energy from a black hole. [1] https://en.wikipedia.org/wiki/Penrose_process [2] https://www.popularmechanics.com/space/a14524087/black-holes-mass-energy/
质疑认为戴森球在科学上不合理:能建造它的文明早已掌握更高效的聚变能源
戴森球这个概念本身有点愚蠢。任何有能力建造戴森球的文明,大概率已经能高效地实现核聚变发电。没必要跑到几百万公里外去收集恒星的能量,直接在本地用更少的资源和材料生产即可——太阳本身产能效率其实很低。唯一合理的戴森球用途是给过热的恒星降温、反射掉多余能量,而不是收集能量。它是很好的科幻题材,但科学上讲不通。
ardit33查看英文原文
The whole concept of a Dyson sphere is kinda idiotic. Any civilization that is capable to build one, it is probably able to work out fusion energy very efficiently. There is no point to go and harness energy around a star or a black hole, when you can just produce it locally with a lot less resources/waste and materials. The sun itself is actually very inefficient in producing energy. There is no need to harness the sun million of km away, when you can recreate it in your home planet. The only way to produce a dyson like of sphere, is to tame an over-heated sun, and reflect away un-needed energy. But there is no point to build one to just harness it. It makes great sci-fi stories, but that's about it. Scientifically, it just doesn't make sense.
补充总结论文核心结论:吸积盘和喷流才是黑洞周边的主要可用能源
更好的链接是 arXiv 原文。结论相当直白:CMB 和霍金辐射提供的功率几乎为零,而吸积盘和相对论喷流可以提供大量能量。
saagarjha查看英文原文
Better link: https://arxiv.org/abs/2106.15181 The results are fairly obvious: CMB and Hawking radiation provide almost zero power output, while an accretion disk and relativistic jets can provide a lot of power.
亲历分享游戏《戴森球计划》中围绕黑洞建造戴森球的实况视频
天哪,我自己刚在游戏里建了一个小型黑洞戴森球!虽然没论文里那么宏伟(附多个《戴森球计划》游戏实况视频链接)。如果你不知道这个游戏——可以把它想象成太空版 3D Factorio。
DonHopkins查看英文原文
Holy plate of shrimp: I just built a small Dyson Sphere around a black hole, all by myself! Not quite as big and majestic as these though: Black Hole Dyson Sphere TIMELAPSE | Dyson Sphere Program https://www.youtube.com/watch?v=oEpTaXRIhE0&ab_channel=Nilaus [Timelapse] Dyson Sphere around Black Hole (Dyson Sphere Program) https://www.youtube.com/watch?v=HXwrePn_JJc&ab_channel=Pasukaru Dyson Sphere Program - FLYING INTO A BLACK HOLE! https://www.youtube.com/watch?v=nIYooegxSQI&ab_channel=OneLastMidnight In case you don't know what Dyson Sphere Program is -- think 3D Factorio in Space: Dyson Sphere Program Trailer https://www.youtube.com/watch?v=PJ3fDcm5qaQ&ab_channel=GameraGame Dyson Sphere Program Release Date Announcement Trailer https://www.youtube.com/watch?v=Eh-voJ3TSt8&ab_channel=GameraGame Katherine of Sky has some great DPS videos, and she also plays lots of Factorio and Satisfactory too: Dyson Sphere Program Ep 1 - Factorio + Satisfactory + Astroneer = FUN? - Let's Play, Early Access https://www.youtube.com/watch?v=fScIOw07QRw&list=PL4o6UvJIdPNpJIYf0NexLTLwk9UosUHMO&ab_channel=KatherineOfSky
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