Black holes and their boundaries: from equilibrium properties to how dynamical black holes interact with their environment

黑洞及其边界：从平衡特性到动态黑洞如何与其环境相互作用

• 批准号: 261429-2013
• 负责人: Booth, Ivan
• 金额: $ 3.21万
• 依托单位: Memorial University of Newfoundland
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2016
• 资助国家: 加拿大
• 起止时间: 2016-01-01 至 2017-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=594558
• 关键词: Black; holes; their; boundaries; equilibrium

As the moon orbits the Earth, its gravitational field raises the tides. As the tidal bulges flow around the globe, friction between the water and land slows the Earth's rotation. At the same time, the gravitational field of the bulges pulls back on the moon and so terran rotational angular momentum is transformed into lunar orbital angular momentum. As in any problem involving friction, energy is dissipated and a net effect of this gravitational coupling is that the moon recedes from the Earth at a rate of almost 4cm/year. This process nicely demonstrates how we reason in classical physics. The geometry (in this case the shape of the tidal bulge and orbital distance to the moon) interacts with the gravitational field and drives a transfer of energy and angular momentum around the system. Once we know about the forces and the flows of energy and momentum, we feel that we understand the system.

当月球绕地球运行时，它的引力场会引起潮汐。当潮汐隆起在全球流动时，水和陆地之间的摩擦减慢了地球的自转。同时，凸起的引力场向后拉月球，因此人类自转角动量转化为月球轨道角动量。与任何涉及摩擦的问题一样，能量会被耗散，这种引力耦合的净效应是月球以每年近 4 厘米的速度远离地球。这个过程很好地展示了我们如何在经典物理学中进行推理。几何形状（在本例中为潮汐隆起的形状和到月球的轨道距离）与引力场相互作用，并驱动系统周围的能量和角动量的转移。一旦我们了解了力以及能量和动量的流动，我们就会觉得我们了解了这个系统。