Proposed Tests Of Relativity On The International Space Station

A recent paper published by Fundamental Physics investigator Alan Kostelecky of Indiana University and graduate student Matt Mewes examines tests of Einstein's Special Relativity using the Superconducting Microwave Oscillator (SUMO) experiment on the International Space Station (ISS).

Kostelecky's group has developed a general theoretical framework to study tiny violations of Relativity, spurred by the idea that new physics such as string theory may reveal itself in this way. The theory suggests various experiments to test Relativity and can be used to analyse them.

Among the traditional tests of Einstein's Special Relativity are the famous Michelson-Morley experiment and its variants. These tests establish a key element of special relativity: the speed of light is independent of the speed of the source and is the same in all directions.

The new paper studies the use of the SUMO apparatus as a refined Relativity test of this type. The exceptional sensitivity of the SUMO oscillator clock and its placement on the rapidly orbiting ISS lead to unique signals that are difficult to achieve on Earth.

The paper appears in the journal Physical Review D 66 056005 (2002) of 1 September 2002. The article is also available online at Background information can be found at