Norbert Wex
Max-Planck-Institut für Radioastronomie, Bonn
Before the 1970s, precision tests for gravity theories were constrained
to the weak gravitational fields of the Solar system. Hence, only the
weak-field slow-motion aspects of relativistic celestial mechanics could
be investigated. Testing gravity beyond the first post-Newtonian
contributions was for a long time out of reach.
The discovery of the first binary pulsar by Russell Hulse and Joseph
Taylor in the summer of 1974 initiated a completely new field for
testing relativistic gravity. For the first time the back reaction of
gravitational wave emission on the binary motion could be studied, which
gave the first evidence for the existence of gravitational waves as
predicted by Einstein’s general relativity. Furthermore, the
Hulse-Taylor pulsar provided the first test bed for the gravitational
interaction of strongly self-gravitating bodies.
To date there are a number of radio pulsars known, which can be utilized
for precision test of gravity. Depending on their orbital properties and
their companion, these pulsars provide tests for various different
aspects of gravity. Besides tests of specific theories, like general
relativity or scalar-tensor gravity, there are pulsars that allow for
generic constraints on deviations of gravity from general relativity in
the quasi-stationary strong-field regime and in the generation of
gravitational waves.
I my talk I give an introduction to gravity tests with radio pulsars,
and highlight some of the most important results. In addition, I give a
brief outlook into the future of this exciting field of experimental
gravity.