Dark matter is believed to be part of the missing mass.

暗物质也被认为是遗失质量的一部分。

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If so, the mystery of dark matter (much of the universe's missing mass) could be solved in addition to creating a more formidable standard model of physics.

如果是这样的话，暗物质(宇宙中遗失的大团中的很多)的神秘性在创造出一个物理学上更强大的标准模型的条件下就可以被揭开了。

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Astronomers have long speculated that the missing baryonic mass might eventually be discovered in intergalactic space or as some large population of galaxies that are difficult to detect.

天文学家长期以来都在推测，最终可能会在星际空间或者是在难以探测的大量星系中发现丢失的重子质量。

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The leading theory to explain the missing neutrinos was that neutrinos had a little mass, which it turns out would allow them to transform themselves as they traveled from one neutrino type to another.

NPR: Neutrinos: A Cursed Subatomic Particle?

For a few months in 2010 it looked as though the Tevatron might get a reprieve in order to find the last (and heaviest) missing bit of the model the Higgs boson, which is thought to give other particles their mass.

ECONOMIST: The future of physics (1)