Measurements of Gravity-Like Forces at Small Distances

该项目使用一种新型仪器来测量10微米到100微米范围内的类重力力，在这个长度范围内，估计灵敏度为牛顿重力的阶。该技术类似于微型卡文迪许式实验，用悬臂梁的弹簧代替原来的扭转平衡。第一代仪器已经建成并经过测试，在一个新的排除范围内产生了第一组数据，该范围在大约10微米的长度范围内提高了四个数量级以上的相互作用强度。预计该项目将对各个层面的科学产生影响。首先，所有试图将万有引力与自然界其他力统一起来的理论都涉及到对牛顿万有引力定律的修正。因此，该实验将在目前最令人兴奋的长度尺度范围内指导理论。第一组数据对一大批弦理论提出了新的和重要的限制，在这些理论中，模态粒子有望作为超对称破缺的结果出现。由于牛顿的万有引力定律是年轻学生在小学学习的第一个自然概念之一，因此在短而易于理解的距离上对这一定律的可能修改将点燃年轻人的思想。这个问题变得更加有趣，因为实验中使用的技术处于微型制造设备的前沿。

This project uses a novel apparatus for the measurement of gravity-like forces in the 10 micrometer to 100 micrometer range, having an estimated sensitivity of order Newton's gravity at this range of length scales. The technique is similar to that of a miniature Cavendish-type experiment, with the original torsion balance replaced by the spring of a cantilever beam. A first generation of the apparatus was already built and tested yielding a first set of data in a new excluded range which improves previous bounds by more than four orders of magnitudes in interaction strength at the length scale of approximately 10 micrometers.The project is expected to impact science at all levels. First, all theories that attempt to unifygravity with the other forces in nature involve the modification of Newton's law of gravity. The experiment will therefore guide the theory in the currently most exciting range of length scales. The first set of data put new and important constraints on a large class of string theories wheremoduli particles are expected to appear as a consequence of broken supersymmetry. Since Newton's law of gravity is one of the first concepts of nature that young students learnat grade school, the possible modifications of this law at short, but mentally comprehensible, distances will ignite young peoples' minds. The problem becomes even more interesting as the technology used in the proposed experiment is at the cutting edge of micro-fabricated devices.