Effects of spacetime fluctuations

时空涨落的影响

• 批准号: 91114040
• 负责人: Professor Dr. Claus Lämmerzahl
• 金额: --
• 依托单位: Zentrum für angewandte Raumfahrttechnologie und Mikrogravitation (ZARM)
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2009
• 资助国家: 德国
• 起止时间: 2008-12-31 至 2010-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/91114040?language=en
• 关键词: Effects; spacetime; fluctuations

A theory of quantum gravity is far from being complete and experimental verifiable predictions of loop quantum gravity and string theory are still lacking. However, some general predictions are made by such approaches. In quantum gravity phenomenology the missing link between theoretical approach and experiment is overcome by working out possible scenarios in which some physical features are violated. The experimental techniques, necessary for the verification of such phenomenological models, have reached a high level of accuracy and are continuously developed further.The objective of this project is to extend a special model for space-time fluctuations, being a possible outcome of a underlying quantum theory of gravitation. This includes the application of the model to different branches of physics, namely the fermionic sector, photons and macroscopic quantum systems like Bose-Einstein condensates. This leads to modified Maxwell-equations, a modified Dirac equation, the appearance of decoherence and to a modified Gross-Pitaevski equation, where deviations from standard-physics are parameterized within the approach. By comparing with high-sensitivity experiments in the laboratory (e.g. Bose-Einstein condensates, matter-wave interferometry and Michelson-Morley type experiments) and with astrophysical observations (e.g. gamma-ray bursts), this approach allows to set quantitative bounds on possible modifications. The work to be done would lead to a comprehensive - of course not complete - overview over implications of space-time fluctuations on quantum- and classical systems. This is necessary in order to assist in the search for a theory of quantum gravity.

量子引力理论还远未完善，仍然缺乏对圈量子引力和弦理论的可实验验证的预测。然而，一些一般性的预测是通过这种方法做出的。在量子引力现象学中，理论方法和实验之间缺失的联系可以通过找出违反某些物理特征的可能场景来克服。验证此类现象学模型所需的实验技术已达到很高的准确性，并不断得到进一步发展。该项目的目标是扩展时空涨落的特殊模型，这是基础引力量子理论的可能结果。这包括将该模型应用于物理学的不同分支，即费米子扇区、光子和玻色-爱因斯坦凝聚等宏观量子系统。这导致了修改后的麦克斯韦方程、修改后的狄拉克方程、退相干的出现以及修改后的格罗斯-皮塔耶夫斯基方程，其中与标准物理的偏差在该方法中被参数化。通过与实验室中的高灵敏度实验（例如玻色-爱因斯坦凝聚、物质波干涉测量和迈克尔逊-莫雷型实验）以及天体物理观测（例如伽马射线暴）进行比较，这种方法可以对可能的修改设定定量界限。要做的工作将全面（当然不是完整）概述时空涨落对量子和经典系统的影响。为了帮助寻找量子引力理论，这是必要的。