Model-dependence of Shapiro time delay and the 'speed of gravity/speed of light' controversy

  title={Model-dependence of Shapiro time delay and the 'speed of gravity/speed of light' controversy},
  author={Steven Carlip},
  journal={Classical and Quantum Gravity},
  • S. Carlip
  • Published 14 March 2004
  • Physics
  • Classical and Quantum Gravity
Fomalont and Kopeikin have recently succeeded in measuring the velocity-dependent component of the Shapiro time delay of light from a quasar passing behind Jupiter. While there is general agreement that this observation tests the gravitomagnetic properties of the gravitational field, a controversy has emerged over the question of whether the results depend on the speed of light, c, or the speed of gravity, cg. By analysing the Shapiro time delay in a set of 'preferred frame' models, I… 
Comment on ‘Model-dependence of Shapiro time delay and the “speed of gravity/speed of light” controversy’
In a recent paper published in (2004 Class. Quantum Grav. 21 3803) Carlip used a vector–tensor theory of gravity to calculate the Shapiro time delay by a moving gravitational lens. He claimed that
A recent review article by S. Samuel "On the Speed of Gravity and the Jupiter/Quasar Measurement" published as Int. J. Mod. Phys. D13, 1753 (2004), provides the reader with a misleading "theory" of
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Reply to the comment on ‘Model dependence of Shapiro time delay and the “speed of gravity/speed of light” controversy’
I reply to a comment by Kopeikin (2005 Class. Quantum Grav. 22 5181) claiming that a previous paper of mine (Carlip 2004 Class. Quantum Grav. 21 3803) missed a hidden dependence of the Shapiro time
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