Recent VLBA/VERA/IVS Tests of General Relativity

TL;DR

This paper reviews recent high-precision VLBA, VERA, and IVS observational tests of General Relativity, including measurements of gravitational deflection and aberration of gravity, demonstrating the current capabilities and future potential of radio interferometry.

Contribution

It presents recent experimental results and discusses the limits and future prospects of using VLBA, VERA, and IVS arrays for testing General Relativity.

Findings

Measured gamma with 0.0003 accuracy in 2005 VLBA experiment

Upcoming experiments aim for 0.01 mas positional accuracy

Discussed limits and future improvements in radio-based tests of gravity

Abstract

We report on recent VLBA/VERA/IVS observational tests of General Relativity. First, we will summarize the results from the 2005 VLBA experiment that determined gamma with an accuracy of 0.0003 by measuring the deflection of four compact radio sources by the solar gravitational field. We discuss the limits of precision that can be obtained with VLBA experiments in the future. We describe recent experiments using the three global arrays to measure the aberration of gravity when Jupiter and Saturn passed within a few arcmin of bright radio sources. These reductions are still in progress, but the anticipated positional accuracy of the VLBA experiment may be about 0.01 mas.