charles 2009-3-27 11:07
奇異宇宙的傳說
Rumors of a Strange Universe
[img]http://i9.tinypic.com/2lmaulf.jpg[/img]
影像提供: High-Z Supernova Search Team, HST, NASA
[color=navy]Explanation:[/color]
[color=dimgray]Eight years ago results were first presented indicating that most of the energy in our universe is not in stars or galaxies but is tied to space itself. In the language of cosmologists, a large cosmological constant is directly implied by new distant supernovae observations. Suggestions of a cosmological constant (lambda) are not new -- they have existed since the advent of modern relativistic cosmology. Such claims were not usually popular with astronomers, though, because lambda is so unlike known universe components, because lambda's value appeared limited by other observations, and because less-strange cosmologies without lambda had previously done well in explaining the data. What is noteworthy here is the seemingly direct and reliable method of the observations and the good reputations of the scientists conducting the investigations. Over the past eight years, independent teams of astronomers have continued to accumulate data that appears to confirm the unsettling result. The above picture of a supernova that occurred in 1994 on the outskirts of a spiral galaxy was taken by one of these collaborations. [/color]
[color=navy]說明:[/color]
[color=dimgray]一些八年前的研究結果，首次透露出宇宙中的大部分能量，似乎並不在恆星與星系內，而是被束縛在太空中。以宇宙學家的語言來說，新的遙遠超新星觀測結果，意味著宇宙有一個很大的宇宙常數。宇宙常數並不是一個新的想法，它早在現代的相對論性宇宙論被提出時，就已經存在的。然而，宇宙常數的主張並不受天文學家的歡迎，因為宇宙常數和宇宙已知特性非常不同，觀測也顯示宇宙常數的值非常小，不需加入宇宙常數的宇宙論，也可以將先前的觀測資料解釋的很好。不過，由聲譽很好的研究團隊所進行的直接、可靠觀測顯示，宇宙常數可能是真實的。在過去八年中，數個獨立的天文研究團隊不間斷地累積觀測數據，證實了這項擾亂現有理論的推測。上面這張一顆1994年發生在螺旋星系外圍的超新星影像，就是由其中一個團隊所拍攝的。[/color]
[size=2]資料來源: Scientific American
Department of Physics, NCKU[/size][color=white][size=1]
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