万物简史 第177期:爱因斯坦的宇宙(20)(在线收听) |
Every object that has mass creates a little depression in the fabric of the cosmos. 凡有质量的物体在宇宙的底垫上都能造成一个小小的凹坑。
Thus the universe, as Dennis Overbye has put it, is "the ultimate sagging mattress."
因此,正如丹尼斯·奥弗比说的,宇宙是个“最终的下陷底垫”。
Gravity on this view is no longer so much a thing as an outcome,
从这个观点来看,引力与其说是一种东西,不如说是一种结果,
"not a 'force' but a byproduct of the warping of spacetime," in the words of the physicist Michio Kaku, who goes on:
用物理学家米奇奥·卡库的话来说:“不是一种‘力’,而是时空弯曲的一件副产品。”卡库接着又说:
"In some sense, gravity does not exist; what moves the planets and stars is the distortion of space and time."
“在某种意义上,引力并不存在;使行星和恒星运动的是空间和时间的变形。”
Of course the sagging mattress analogy can take us only so far because it doesn't incorporate the effect of time.
当然,以下陷的底垫来作比喻,只能帮助我们理解到这种程度,因为没有包含时间的作用。
But then our brains can take us only so far
话虽这么说,其实我们的大脑也只能想像到这个地步。
because it is so nearly impossible to envision a dimension comprising three parts space to one part time,
因为这几乎是不可能的——若要想像空间和时间以3:1的比例
all interwoven like the threads in a plaid fabric.
像线织成一块格子地垫那样织成一份时空。
爱因斯坦的珍贵照片
At all events, I think we can agree that this was an awfully big thought for a young man staring out the window of a patent office in the capital of Switzerland.
无论如何,我想我们会一致认为,对于一位凝视着瑞士首都专利局窗外的年轻人来说,这确实是个了不起的见解。
Among much else, Einstein’s general theory of relativity suggested that the universe must be either expanding or contracting.
爱因斯坦的广义相对论提出了许多见解。其中,他认为,宇宙心总是或者膨胀或者收缩的。
But Einstein was not a cosmologist, and he accepted the prevailing wisdom that the universe was fixed and eternal.
但是,爱因斯坦不是一位宇宙学家,他接受了流行的看法,即宇宙是固定的,永恒的。
More or less reflexively, he dropped into his equations something called the cosmological constant,
多少出于本能,他在自己的等式里加进了他所谓的宇宙常数。
which arbitrarily counterbalanced the effects of gravity, serving as a kind of mathematical pause button.
他把它作为一种数学暂停键,武断地以此来抵消引力的作用。
Books on the history of science always forgive Einstein this lapse,
科学史书总是原谅爱因斯坦的这个失误,
but it was actually a fairly appalling piece of science and he knew it.
但这其实是科学上一件很可怕的事。
He called it "the biggest blunder of my life."
他把它称之为“我一生中所犯的最大错误”。 |
原文地址:http://www.tingroom.com/lesson/syysdw/wwwjs/386334.html |