Feasibility for Testing the Equivalence Principle with Optical Readout in Space

A concept of testing the equivalence principle with optical readout in space (TEPO) has been proposed J. Jpn. Soc. Microgravity Appl. 25 (2008) 423. We further discuss the feasibility of TEPO using LISA (laser interferometer space antenna) Pathfinder technologies, such as a heterodyne interferometer, an inertial sensor, drag-free control and discharge technique, and determine that the equivalence principle could be tested at 8×10⁻¹⁷ with one day integration.