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Tests of general relativity from timing the double pulsar
M Kramer1, I H Stairs, R N Manchester
1University of Manchester, Jodrell Bank Observatory, Macclesfield SK11 9DL, UK. mkramer@jb.man.ac.uk
Science (New York, N.Y.)
|September 16, 2006
Summary
The double pulsar system PSR J0737-3039A/B provides the most precise test of general relativity to date. Its unique orbital dynamics confirm Einstein's theory with 0.05% accuracy, advancing gravitational physics.
Area of Science:
- Astronomy and Astrophysics
- Gravitational Physics
Background:
- The double pulsar system PSR J0737-3039A/B is unique as both neutron stars are detectable radio pulsars.
- It exhibits higher orbital velocities and accelerations than other binary pulsars, making it ideal for strong-field gravity tests.
Purpose of the Study:
- To conduct precision timing observations of the double pulsar system.
- To perform strong-field tests of general relativity and alternative theories of gravity.
Main Methods:
- Utilized 2.5 years of precision timing observations of PSR J0737-3039A/B.
- Measured relativistic corrections to Keplerian orbital motion using a theory-independent mass ratio.
Main Results:
- Achieved the most precise test of general relativity to date, with the post-Keplerian parameter 's' agreeing with predictions to within 0.05% uncertainty.
- Determined an extremely small transverse velocity for the system's center of mass.
Conclusions:
- The double pulsar system offers unparalleled opportunities for future tests of gravitational theories, potentially surpassing current solar system tests.
- The findings suggest alternative formation scenarios for the second-born pulsar, challenging the core collapse of a helium star hypothesis.
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