万物简史 第246期:马斯特-马克的夸克(18)(在线收听) |
This is counter to all expectations. It appears that the universe may not only be filled with dark matter, but with dark energy. Scientists sometimes also call it vacuum energy or, more exotically, quintessence. Whatever it is, it seems to be driving an expansion that no one can altogether account for. The theory is that empty space isn't so empty at all—that there are particles of matter and antimatter popping into existence and popping out again—and that these are pushing the universe outward at an accelerating rate. Improbably enough, the one thing that resolves all this is Einstein's cosmological constant—the little piece of math he dropped into the general theory of relativity to stop the universe's presumed expansion, and called "the biggest blunder of my life." It now appears that he may have gotten things right after all. 这与人们的期望是背道而驰的。看来宇宙不仅充满暗物质,而且充满暗能量。科学家们有时将这称之为真空能或第五元素。无论如何,宇宙似乎在不断膨胀,谁也说不清这是什么道理。有理论认为,空空荡荡的太空其实并不空空荡荡──物质和反物质的粒子在不停地产生和消失──是它们在把宇宙以越来越快的速度往外推移。令人不可思议的是,解决这一切的恰恰是爱因斯坦的宇宙常数──他为了驳斥关于宇宙在不断膨胀的假设而在广义相对论里顺便引入的,也是他自称是“我一生中最大的失误”的那个小小的算式。现在看来,他毕竟还是对的。
夸克星
The upshot of all this is that we live in a universe whose age we can't quite compute, surrounded by stars whose distances we don't altogether know, filled with matter we can't identify, operating in conformance with physical laws whose properties we don't truly understand.
归根结底,我们生活在一个宇宙里,它的年龄我们算不大清楚;我们的四周都是恒星,它们到我们的距离以及它们彼此之间的距离我们并不完全知道;宇宙里充满着我们无法识别的物质;宇宙在按照物理学定律运行,这些定律的性质我们并不真的理解。
And on that rather unsettling note, let's return to Planet Earth and consider something that we do understand—though by now you perhaps won't be surprised to hear that we don't understand it completely and what we do understand we haven't understood for long.
以这样的一种很不确定的基调,让我们再回到地球,考虑一下我们确实理解的东西──虽然到目前为止,要是你听到我们并没有完全理解它这类话,你也许不会再感到吃惊──以及我们长期以来不理解而现在理解了的东西。 |
原文地址:http://www.tingroom.com/lesson/syysdw/wwwjs/407098.html |