Gravitational Radiation

将为2008- 2010年期间在LIGO（激光干涉仪引力波天文台）中运行的先进引力波探测器发明新的设计;将通过理论分析预测这些新探测器的性能。 这些新探测器的主要目标将是规避一种新型的噪声，这种噪声将在探测器改进到2008-2010年预期的水平时出现;噪声是由于LIGO中反射镜的量子力学行为引起的，它会响应通过的引力波而移动。 这些新的探测器被称为“量子非破坏”（QND）引力波探测器，因为它们将使引力波信号避免被镜子的量子力学行为破坏。 进一步的理论研究将集中在这些QND探测器（以及LIGO中的其他先进探测器）必须面对的其他类型的噪声，以及如何控制这些噪声。 这些其他噪音包括来自地球大气湍流的波动引力和探测器下方地面的微弱地震波，以及LIGO镜子中原子热振动的噪音。 最后，开展各种引力波源的理论研究，为LIGO数据分析软件的设计提供指导，为LIGO引力波搜索和观测的规划提供指导，为LIGO科学技术能力的长期提升奠定基础。 因此，它将有助于大大扩大宇宙的体积，LIGO可以通过它来搜索碰撞黑洞和其他引力波源。 QND的研究还具有更广泛的意义：它是“量子计量学”新领域的前沿部分-一种二十一世纪的技术，将利用、操纵和控制宏观物体的量子力学行为，并将操纵量子力学信息。

New designs will be invented for advanced gravitational-wave detectors to operate in LIGO (the Laser Interferometer Gravitational-Wave Observatory) in the 2008--2010 time frame; and the performance of these new detectors will be predicted by theoretical analyses. The principal goal of these new detectors will be to circumvent a new type of noise that will arise when the detectors are improved to the level expected in 2008-2010; noise due to the quantum mechanical behavior of the mirrors in LIGO, which move in response to passing gravitational waves. These new detectors are called "Quantum-Nondemolition" (QND) gravitational-wave detectors because they will enable the gravitational-wave signal to evade being demolished by the quantum mechanical behavior of the mirrors. Additional theoretical studies will focus on other types of noise that these QND detectors (and other advanced detectors in LIGO) must face, and on how to control these noises. These other noises include fluctuating gravitational forces from turbulence in the earth's atmosphere and from weak seismic waves in the ground beneath the detectors, and noise from thermal vibrations of atoms in LIGO's mirrors. Finally, theoretical studies of various sources of gravitational waves will be carried out, with the goal of providing guidance for the design of LIGO's data analysis software, and guidance for the planning of LIGO's gravitational-wave searches and observations.This research will lay foundations for long-term improvements of LIGO's scientific and technical capabilities. It will thereby help to expand greatly the volume of the universe through which LIGO can search for colliding black holes and other sources of gravitational waves. The QND research also has broader implications: It is a forefront portion of the new field of "quantum metrology"---a twenty-first century technology that will make use of, manipulate, and control the quantum mechanical behavior of macroscopic objects, and will manipulate quantum mechanical information.