标题： 地外文明的探测极限 显示英文标题

标题： Limits of Detecting Extraterrestrial Civilizations

摘要： 寻找地外智慧生命（SETI）是一项科学探索，它面临着独特的难题——在寻找什么数据以及何时进行寻找方面存在强烈的不确定性。 这导致了对地外智慧与人类文明之间通信的基本极限的尝试性研究，以及设定基准以预测我们最可能期待的信号类型。 以前的工作是用信息论中的通信任务来表述的，但我们则认为它应该被看作一个检测问题，具体来说是一个一次性（非对称）假设检验。 通过这种新的解释，我们建立了基本极限，并提供了简单的例子，说明如何使用这个框架来分析和评估来自地外文明的不同可能信号。 我们证明了用于检测的电磁信号所需的功率远低于通信所需的功率，检测作为功率函数可以是非线性的，并且在这个框架中的大部分分析可以通过计算高效的优化问题来解决，从而展示了进一步探究的工具。 显示英文摘要

摘要： The search for extraterrestrial intelligence (SETI) is a scientific endeavor which struggles with unique issues -- a strong indeterminacy in what data to look for and when to do so. This has led to attempts at finding both fundamental limits of the communication between extraterrestrial intelligence and human civilizations, as well as benchmarks so as to predict what kinds of signals we might most expect. Previous work has been formulated in terms of the information-theoretic task of communication, but we instead argue it should be viewed as a detection problem, specifically one-shot (asymmetric) hypothesis testing. With this new interpretation, we develop fundamental limits as well as provide simple examples of how to use this framework to analyze and benchmark different possible signals from extraterrestrial civilizations. We show that electromagnetic signaling for detection requires much less power than for communication, that detection as a function of power can be non-linear, and that much of the analysis in this framework may be addressed using computationally efficient optimization problems, thereby demonstrating tools for further inquiry.