Probing the Equation of State of the Dark Energy with Supernovae.

AST-0507475 Stubbs当今物理学中最紧迫的未决问题之一涉及驱动宇宙加速膨胀的暗能量的性质。 尽管目前几乎没有人怀疑暗能量代表了一些新的和基本的物理学，但仍然需要区分其性质的各种可能性：它是引力，驻留在爱因斯坦的宇宙常数中，还是奇异物质，来自真空中的量子力学过程？ 该项目继续进行一项雄心勃勃的调查，目前已完成一半，使用大约200颗红移在0.2和0.8之间的Ia型超新星来绘制宇宙的膨胀历史。 它应该能够限制一个关键的暗能量参数，其分数不确定性仅为10%。许多本科生和研究生都参与了这个前沿研究项目，它所需的NSF支持的望远镜的增强功能使该设施的所有用户受益。 由于暗能量的本质是一个谜，吸引了公众的想象力，项目成员将继续积极参与关于这一主题的正式和非正式教育活动。

AST-0507475StubbsOne of today's most pressing open questions in physics concerns the nature of the dark energy driving the accelerating expansion of the Universe. Although there is currently little doubt that dark energy represents some new and fundamental physics, there is still a need to distinguish between various possibilities for its nature: is it gravitational, residing in Einstein's cosmological constant, or exotic matter, coming from quantum mechanical processes in the vacuum? This project continues an ambitious survey, currently about half complete, to use some 200 Type Ia supernovae between redshifts of 0.2 and 0.8 to map out the expansion history of the Universe. It should be able to constrain a critical dark energy parameter with a fractional uncertainty of only 10%.Many undergraduate and graduate students have been involved in this cutting-edge research project, and the enhanced capabilities it required at an NSF-supported telescope have benefited all users of that facility. Since the nature of the dark energy is a mystery that has captivated the imagination of the general public, project members will continue to be very engaged in both formal and informal educational activities on this topic.