我郑重说明，这些文章都是Rojer.自己翻译的！
为方便观看原文如下
Dark matter mapped
First three-dimensional picture of elusive matter throws up mystery.
Hot on the heels of evidence last year that dark matter really does exist (see 'Dark matter spied in galactic collision'), the same technique has been used to map this uncharacterized mass across half a million distant galaxies.
The map shows that, as predicted, the mysterious dark matter that makes up a quarter of the Universe forms a filamentous 'skeleton' upon which visible matter congregates, eventually producing stars. This is the first time such a large-scale three-dimensional picture of dark matter has been produced, and it will allow cosmologists to probe deeper into the nature of this elusive matter.
But the map, published in Nature1, also has a few puzzles within it. Some areas show clumps of dark matter that aren't accompanied by the bright features associated with conventional, visible material (made of baryonic matter), and vice versa.
"On the large scale the general picture is as expected, but there are some small-scale discrepancies," says Richard Massey at the California Institute of Technology, Pasadena, and one of the team members who pieced together the map from hundreds of slightly overlapping images from the Hubble Space Telescope's Cosmic Evolution Survey (COSMOS).
The existence of large clumps of isolated dark matter and visible matter flies in the face of everything we know, says cosmologist Carlos Frenk of the University of Durham, UK.
The discrepancies could be a simple error resulting from the way the observations were made. But if they are real, says Massey, they will bring a huge shock. "Baryonic structures are expected to form only inside the dark-matter scaffold," he says. "There will need to be a lot of follow-up work before we really believe any individual discrepancies."
A light pull
Massey used a technique called gravitational lensing, whereby the pull from dark matter caught in between a star and the observing telescope alters the path of the light, and allows the presence of dark matter to be inferred.
Eric Linder of the University of California, Berkeley, who was not involved with the work, agrees that the map backs up the favoured theory that dark matter forms a scaffold on which galaxies form.
He suggests possibilities for the more unusual spots in the map: one is that galaxies made of dark matter (dark galaxies) exist, but he thinks this is unlikely. Another possibility is that the discrepancies are errors in the data — which seem almost inevitable given that mapping the dark matter required a very sensitive measurement of an incredibly small signal. "Right now the discrepancies are curiosities rather than items of concern," Linder says.
Massey is also confident in the robustness of his map on the whole. "A couple of individual discrepancies in the map are not a huge surprise," he says. "The technique is intrinsically more noisy, and more prone to systematic errors, near the edges of the map." That is where most of the discrepancies are seen.
Blown away
There are plausible explanations for small areas of dark matter and visible matter existing in isolation.
Dark matter, if the clump is small enough, could have any accumulating visible matter blown out of it by a high-energy phenomenon such as a quasar or a supernova, for example. The collision of two galaxies could also blow an amount of visible matter out as a faint satellite galaxy that has no associated dark matter, suggests Frenk.
But these theories can't explain the large features visible on the COSMOS map, he adds.
Like Massey and Linder, Frenk also suspects that the discrepancies are due to errors: "We know too much about the Universe," he says, to have completely missed this phenomenon up till now. 在我看来（我的直觉是）,也许应当努力将暗物质的研究与中微子研究加以衔接.
通过这条途径,也许可以将在天上观察到模糊影象与地上测量中的、曾经的守恒漏洞连接起来.
但是中微子是暗物质的可能性已经很小了。
Re: 绘制暗物质图
绘制暗物质图首幅不宜被发现的神秘物质3维图像
http://www.nature.com/news/2007/070101/images/070101-7.jpg
暗物质（图中的等高线）的集中通常但并不总是与正常物质（图中色彩部分）相符。
紧追着去年暗物质确实存在的脚步，同样的技术被用来绘制50万光年远的星系中的这种毫无特征的物质。
该图如同预知的那样显示出占宇宙质量1/4的神秘暗物质形成纤维状“骨架”，在此之上可见物质聚集最终形成恒星。这是第一次制作出暗物质如此大尺度的三维图像，宇宙学家可以借此更深一步探查这种难以捉摸物质的本性。
但在《自然》上发表的这张图仍然存在一些谜团。一些成团块的暗物质并没有与明亮的普通可见物质相伴，反之亦然。
加州理工学院的 Richard Massey 表示：“在大尺度上该概要图与预期一致，但是在一些小尺度上有差异。”Richard Massey 所在的小组将数百幅互有重叠的“哈勃”宇宙演化考察(COSMOS)图拼在了一起。
英国 Durham 大学的 Carlos Frenk 认为，大团孤立的暗物质和可见物质的存在公然与我们所知的一切相违反。
此差异或许是观测方法产生的单纯误差。但如果它是真的，Massey 表示，那会带来巨大的震动。“重子结构被认为是只能在暗物质脚手架内部形成。在我们真正相信任何一个独立的差异之前还要做大量的工作。
Massey 用一种称为“引力透镜”的技术，就是在星体与观测的望远镜之间的暗物质会牵引改变光的路径，借此推断暗物质的存在。
加州大学伯克利分校的 Eric Linder 虽未参与此项工作，但同样认为此图是对流行的理论：暗物质为星系的形成搭了架子的支持。
他暗示图中比较的不寻常的点有可能是：存在由暗物物质形成的星系（暗星系），不过他觉得这个不太可能；另一个可能是数据误差引起的差异——绘制暗物质图需要一种对异常微弱的信号很敏感的测量方法，这几乎不可避免的会带来误差。Linder 说：“现在差异成了比项目本身还受关注的稀罕物。”
Massey 对他的图整体上的稳健性充满自信。“图中的几个差异并不是大的意外，技术本身就存在固有的噪声，并且在图的边缘更倾向于系统误差。”那里有较多的差异存在。
对小范围的暗物质与可见物质孤立的存在有着一些似是而非的解释。
Frenk 指出，如果暗物质的团块足够小，会把任何正在积聚的可见物质通过某种像类星体或超新星那样的高能现象吹出去。比如，两个星系的碰撞会把相当一部分可见物质作为一个黯淡的卫星星系刮出去，那与暗物质没有联系。
但他补充道，这种理论不能解释 COSMOS 图上出现的大特征。
与 Massey 和 Linder 一样，Frenk 也怀疑那些差异是误差造成的。
Original原文：http://www.nature.com/news/2007/070101/full/070101-7.html
楼主好样的,翻译得不错!赞一个! ^^ 在我看来（我的直觉是）,也许应当努力将暗物质的研究与中微子研究加以衔接.
通过这条途径,也许可以将在天上观察到模糊影象与地上测量中的、曾经的守恒漏洞连接起来.
但是中微子是暗物质的可能性已经很小了。
如果可能,请说得详细一些.
中微子如果是暗物质的话，应当时所谓“热”暗物质。但是热暗物质预言的结构形成是从大到小的一个过程，热暗物质会“抹平”小尺度的扰动。这与观测和理论均不吻合。 在你发言的时候,我在编辑前面的帖子,有一段值得抄过来:
"值得说明的是,人们默认中微子以光速运动,其实至尽并没有直接测量结果.被称为"中微子"那种东西在产生以后高速地离开了,还是留在原处,逐渐弥散,并没有直接测量结果."
如果是这样的话,也是可以比较凉的.
如果被称为"中微子"那种东西他们之间有比较强的相互作用,碰撞使其减速,甚至凝聚.
当然,这肯定与现代已经形成的观念相差许多.
但是,没有明确的实验数据否定这种可能性.
所以我说中微子作为暗物质的可能性很小，并没有说完全不可能。你完全可以构造各种奇怪粒子模型，用来迎合暗物质方面的观测和理论，事实上也确实有人在做这方面的研究，提出过一些复杂的奇怪的中微子模型。
但是我不太关注这个。
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