Gravitational time delays, observed in strong lens systems where the variable background source is multiply imaged by a massive galaxy in the foreground, provide direct measurements of cosmological distance that are very complementary to other cosmographic probes. The success of the technique depends on the availability and size of a suitable sample of lensed quasars or supernovae, precise measurements of the time delays, accurate modeling of the gravitational potential of the main deflector, and our ability to characterize the distribution of mass along the line of sight to the source. We review the progress made during the last 15 years, during which the first competitive cosmological inferences with time delays were made, and look ahead to the potential of significantly larger lens samples in the near future.

中文翻译：

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延时宇宙学

在强透镜系统中观察到的引力时间延迟，其中可变背景源被前景中的一个大质量星系多次成像，提供了与其他宇宙学探测器非常互补的宇宙距离的直接测量。该技术的成功取决于透镜类星体或超新星的合适样本的可用性和大小、时间延迟的精确测量、主偏转器引力势的准确建模，以及我们描述质量沿轨道分布的能力。视线到源头。我们回顾了过去 15 年取得的进展，在此期间首次进行了具有时间延迟的竞争性宇宙学推断，并展望了在不久的将来显着更大的透镜样本的潜力。