空间钟与基础物理测试

Space Clocks and Fundamental Physics Tests

原子钟当前已经发展到很高的水平,它们在空间科学试验中发挥了重要的作用．该文介绍了世界上正在开展的高精度空间钟计划及其对科学测量的意义．对应用空间钟可能进行的某些感兴趣的基础物理测试也进行了描述。

In the last decades since the advent of Einstein＇s General Theory ,astronomical observation has benefited greatly from the ongoing developments of high technology that has led to the discovery of many exciting new physical phenomena, such as the highly energetic apparently extremely distant quasi-steller objects, pulsars and the phenomena relating to superdense matter in the form of neutron stars and the discovery of black holes. All these have added to the interest in experimental tests of the General Theory of Relativity and its comestone, the Principle of Equivalence, and have led us to refocuse our attention on the validity of the Einstein Theory of Gravitation and Relativity and have led to a number of competing theories, which, in turn, have led us to continue thinking of experiments to confirm or deny the validity of these theories. Today, one of the most precise tools for testing these theories is the time or frequency standards（clock）. The last fifty years have been a period of outstanding developments in the field of atomic frequency standards. At the present day, frequency stabilities reach 10^-16 range in hydrogen masers and accuracies are better than 1× 10^-15 in cold atomic clock. They will play a fundamental role in the space scientific measurements. This paper introduces some space clock schemes and experiments with ACES （Atomic Clock Ensemble in Space） which are being proceeded abroad and are to be performed in the microgravity enviroment of the International Space Station as well as the significance of high precision space clocks to scientific testing. Several fundamental physics tests of current interest with space clocks, such as the test of universality of the gravitation red shift, the test of the constancy of the speed of light as well as the test of the time dependence of fine structure constant are also outlined in this paper.