一维或二维空间，引力波无法存在

双语：科学家称宇宙形成初期可能一维空间

教育中国-中国网 edu.china.com.cn　　时间： 2011-04-23 09:10　　责任编辑: 香颂

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Did the early universe have just one spatial dimension? That's the mind-boggling question at the heart of a theory scientists say they are on the brink of solving。 The theory was first proposed by physicist Dejan Stojkovic and colleagues from the University of Buffalo in 2010. They suggested that the early universe - which exploded from a single point and was tiny at first- was one-dimensional (like a straight line) before expanding to include two dimensions (like a plane) and then three, which is the world in which we live today. The theory, if valid, would address important conundrums facing particle physicists。 Now, in a new paper in Physical Review Letters, Stojkovic and colleagues have come up with a test that could prove or disprove the "vanishing dimensions" hypothesis. Because it takes time for light and other waves to travel to Earth, telescopes can, essentially, look back into time as they probe the universe's outer reaches. Gravitational waves can't exist in one or two-dimensional space. So Stojkovic reasons that a planned gravitational observatory (LISA) should not detect any gravitational waves emanating from the early universe。 Stojkovic says the theory of evolving dimensions represents a radical shift from the way we think about how our universe came to be. The theory also suggests that space has fewer dimensions at very high energies of the kind associated with the early, post-big bang universe。 If correct it may help to address the incompatibility between quantum mechanics (used to describe the universe of the very small) and general relativity (good at describing the universe on a large scale。) It could also explain why the expansion of the universe is speeding up with the addition of a fourth dimension。 宇宙形成初期是否只有一个空间维度？这已成为科学家即将攻克的某理论的核心问题。 这个想法最早由布法罗大学的理论物理学家德扬·斯托伊科维奇及其同事在2010年提出。他们认为，宇宙经由某点爆炸形成，初期微小且是一维(像一条直线)，随后膨胀成二维(像一个平面)，最后形成我们如今生活的三维空间。这个理论如能被证实，或许就能解决粒子物理学家面临的重要难题。 在《物理评论快报》的一份新论文中，斯托伊科维奇博士和他的同事们提出一种可证明“消失中的维度”这一假设是否正确的实验。因为光和波传播到地球需要时间，所以，当望远镜观测太空的时候，本质上是在回望过去。在一维或二维空间，引力波无法存在。所以，斯托伊科维奇博士认为，已计划完善的引力波观测站(LISA)无法发现任何早期宇宙的引力波。 斯托伊科维奇博士表示，维度变化的理论将彻底转变人们对宇宙演变的认识和想法。这个理论指出，大爆炸后的早期宇宙，充满了高能量，反而有较少的维数。 如果假设正确，便可以解释量子力学和广义相对论的不兼容原因。量子力学通常描述宇宙的小规模，而广义相对论擅长描述宇宙的大规模。该假设同时也指出随着宇宙的膨胀，将会增加第四个维度。