RUI: Continuation of Support for Short-range Tests of Gravity at Humboldt State University

RUI：继续支持洪堡州立大学的短程重力测试

基本信息

批准号：
1606988
负责人：
Charles Hoyle
金额：
$ 15.6万
依托单位：
Humboldt State University Foundation
依托单位国家：
美国
项目类别：
Continuing Grant
财政年份：
2016
资助国家：
美国
起止时间：
2016-08-01 至 2020-07-31
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=1606988&HistoricalAwards=false
关键词：
RUI Continuation Support Short range

项目摘要

Humboldt State University (HSU) is a federally-recognized Hispanic Serving Institution in a predominantly rural area of Northern California, and the Gravitational Physics Laboratory (GPL) is the only dedicated hands-on physics research laboratory in the Department of Physics and Astronomy. This award ensures that HSU undergraduates, many of whom are first-generation college students and members of underrepresented groups in STEM fields, gain valuable research skills necessary for the pursuit of graduate studies or careers in industry. Undergraduates will also be sent to perform research at the University of Washington through a collaboration formed with a gravity research group there. This collaboration gives the students experience working in a world-class research environment. Alumni of the laboratory have secured prestigious graduate fellowships and industrial positions. This award greatly contributes to the expansion of research at HSU in the STEM fields. Within the major program, software and hardware developed for this project will be transferable to educational opportunities in the upper division classroom. This award also allows undergraduates to participate in valuable dissemination efforts through presentations at national and regional conferences, as well as publication of research results. Finally, tests of gravity are of great interest to research in diverse fields ranging from astrophysics and cosmology to particle physics and precision measurement science. This award supports high-precision experiments that will test the Weak Equivalence Principle (WEP) of General Relativity and the gravitational Inverse-Square Law (ISL) at unprecedented levels. The WEP will be tested at the millimeter scale and the ISL will be probed over sub-millimeter distances with unmatched sensitivity down to approximately 25 microns. Both tests use a novel parallel-plate torsion pendulum and attractor mass design. In recent years the study of the gravitational interaction at short (sub-millimeter) distance scales has gained much attention due in a large part to unification scenarios arising in string or M theory that require more than three spatial dimensions, some of which could be macroscopic. Short-range tests of gravity and the WEP also investigate possible proposed mechanisms that attempt to explain the accelerated expansion of the universe, generally attributed to Dark Energy. Finally, such tests present the possibility to search for hypothetical new interactions due to exotic particles or other phenomena. Many scenarios concerning these effects predict a violation of the WEP or ISL at short distances. Since 1999, experimental limits have improved dramatically so that the ISL has proven valid over distances down to approximately 55 microns. A dedicated test of the WEP, however, has not been performed below the millimeter scale. The work described in this proposal will probe the WEP for test mass separations at the sub-millimeter scale. This measurement will be accomplished with a parallel-plate torsion pendulum design that will provide an essentially null experiment and use multiple composition dipole combinations. Similarly, an unparalleled test of the gravitational ISL will be pursued by decreasing the pendulum/attractor test mass separation to 100 microns.

洪堡州立大学（HSU）是一家在北加州一个主要农村地区的联邦认可的西班牙裔服务机构，重力物理实验室（GPL）是物理和天文学系中唯一的专门动手的物理研究实验室。该奖项可确保Hsu大学生，其中许多是第一代大学生和STEM领域代表性不足的团体成员，获得了从事研究生研究或行业职业所必需的宝贵研究技能。本科生还将通过与重力研究小组组成的合作，在华盛顿大学进行研究。这种合作使学生在世界一流的研究环境中工作的经验。实验室的校友已经确保了著名的研究生奖学金和工业职位。该奖项极大地有助于在STEM领域的HSU扩展研究。在主要计划中，为该项目开发的软件和硬件将可以转移到上层课堂上的教育机会。该奖项还允许大学生通过在国家和地区会议上的演讲以及研究结果的出版来参加有价值的传播工作。最后，重力测试对于从天体物理学和宇宙学到粒子物理学以及精确测量科学的各种领域的研究引起了极大的兴趣。该奖项支持高精度实验，这些实验将在前所未有的水平上测试一般相对论的弱等效原理（WEP）和重力逆方法律（ISL）。 WEP将以毫米尺度进行测试，ISL将在次毫米距离上进行探测，而无与伦比的灵敏度降至大约25微米。两种测试都使用新型的平行扭转摆和吸引子质量设计。近年来，对短（亚毫米）距离尺度的重力相互作用的研究在很大程度上引起了人们对统一场景的很大程度的关注，而弦乐情景或M理论需要三个以上的空间维度，其中一些可能是宏观的。重力和WEP的短距离测试还调查了试图解释宇宙加速膨胀的可能机制，通常归因于暗能量。最后，这样的测试提出了由于外来颗粒或其他现象而引起的假设新相互作用的可能性。有关这些效果的许多场景预测违反了WEP或ISL在短距离内。自1999年以来，实验极限已大大改善，因此ISL已证明在距离上有效至约55微米。但是，对WEP的专门测试尚未在毫米范围以下进行。本提案中描述的工作将探究WEP的测试质量分离，以次数级量表进行测试。该测量将通过平行板扭转摆设计实现，该设计将提供基本无效的实验并使用多个组成偶极组合。同样，将通过将摆/吸引子测试质量分离降低到100微米来进行重力ISL的无与伦比测试。