Effects of spacetime fluctuations

量子引力的理论还远远不完整，环圈量子引力和弦理论的实验可验证预测仍然缺乏。然而，这些方法做出了一些一般性的预测。在量子引力现象学中，理论方法和实验之间缺失的联系是通过计算某些物理特征被破坏的可能场景来克服的。验证这些唯象模型所需的实验技术已经达到了很高的精度水平，并且还在不断地发展。这个项目的目标是扩展一个特殊的时空波动模型，这是一个潜在的量子引力理论的可能结果。这包括将该模型应用于物理学的不同分支，即费米子部门、光子和像玻色-爱因斯坦凝聚体这样的宏观量子系统。这导致了修正的麦克斯韦方程，修正的狄拉克方程，退相干的出现，以及修正的Gross-Pitaevski方程，其中对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-爱因斯坦凝聚体、物质波干涉测量和迈克尔逊-莫利类型实验)和天体物理观测(例如伽马射线暴)进行比较，这种方法允许对可能的修改设定定量界限。要做的工作将导致对时空涨落对量子系统和经典系统的影响的全面--当然不是完整的--概述。为了帮助寻找量子引力理论，这是必要的。

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.