标题： 区分来自伽马射线观测的不同修正色散关系 显示英文标题

标题： Discriminating between different modified dispersion relations from gamma-ray observations

摘要： 早在二十多年前就提出了这样一个事实：由于光子与时空的量子性质相互作用，真空中光子的标准色散关系可能会被修改。 一个定量模型 [Jacob & Piran, JCAP 01, 031 (2008)] 已经通过使用遥远的高能天体物理源进行了广泛的测试，寻找光子到达时间的能量相关延迟。 由于没有测量到明确的延迟，因此对与这些效应相关的能量尺度 $\Lambda$ 设定了下限。 然而近年来，获得了超越 Jacob 和 Piran 模型的不同但同样有根据的光子色散关系表达式，导致了滞后相对于红移依赖关系的不同表达式。 本文引入了一种宇宙学对称性下修正色散关系的通用参数化方法，这直接导致了涵盖现有和新模型的一般参数化的滞后相对于红移依赖关系。 这种参数化方法未来可用于比较不同模型预测的时间延迟，并将其与观测结果进行检验。 为了研究这种可能性，模拟了现实的数据集，模仿了当前和未来仪器检测到的不同类型的河外源。 当在模拟数据中未注入滞后时，正如预期的那样，每个滞后-红移模型都会得出 $\Lambda$ 的不同限制值，而 Jacob 和 Piran 模型给出了最严格的约束。 当在 Jacob & Piran 模型中注入 $\Lambda \sim E_P$ 处的滞后时，它在所有其他考虑的滞后-红移关系中都被检测到，尽管会导致不同的值。 最后，研究了区分几种滞后-红移模型的可能性，强调了在宽范围红移内均匀分布的源样本的重要性。 显示英文摘要

摘要： The fact that the standard dispersion relation for photons in vacuum could be modified because of their interaction with the quantum nature of spacetime has been proposed more than two decades ago. A quantitative model [Jacob \& Piran, JCAP 01, 031 (2008)], has been tested extensively using distant highly energetic astrophysical sources, searching for energy-dependent time delays in photon arrival times. Since no delay was firmly measured, lower limits were set on the energy scale $\Lambda$ related to these effects. In recent years, however, different but equally well-grounded expressions beyond the Jacob \& Piran model were obtained for the photon dispersion relation, leading to different expressions for the dependence of lag versus redshift. This article introduces a general parameterization of modified dispersion relations in cosmological symmetry, which directly leads to a general parameterized lag versus redshift dependence encompassing both existing and new models. This parameterization could be used in the future to compare the predicted time lags of the different models and test them against observations. To investigate this possibility, realistic data sets are simulated, mimicking different types of extragalactic sources as detected by current and future instruments. When no lag is injected in the simulated data, each lag-redshift model leads, as expected, to a different value for the limit on $\Lambda$, and the Jacob \& Piran model gives the most stringent bound. When a lag at $\Lambda \sim E_P$ in the Jacob \& Piran model is injected, it is detected for all the other lag-redshift relations considered, although leading to different values. Finally, the possibility to discriminate between several lag-redshift models is investigated, emphasizing the importance of an evenly distributed sample of sources across a wide range of redshifts.