Are escape-trajectory-only forces possible?

[inottoe]

Just suppose for a moment that various discrepancies in spacecraft trajectories, such as the Earth flyby anomalies, are due to new physics. It’s been pointed out in various sources, for example http://arxiv.org/abs/astro-ph/0608087" , that the spacecraft happen to be on hyperbolic trajectories when the anomalies occur. Further, suppose that this new physics involves forces that only act on an object once it reaches escape velocity from a gravitational source such as the sun or a planet.

The question is: Would such a force cause any obvious violations of the known laws of physics? For example, would it break any conservational laws?

 

[Doc Al]

Just suppose for a moment that various discrepancies in spacecraft trajectories, such as the Earth flyby anomalies, are due to new physics.

If you're talking about the Pioneer anomaly, you might want to read this: https://www.physicsforums.com/showthread.php?t=486509"

 

[Janus]

There is also this:

http://www.universetoday.com/18337/flyby-anomalies-explained/

 

[inottoe]

Well, nothing's definitive just yet. There's http://arxiv.org/abs/1107.2886" from a few days ago.

The main question is whether or not a statistically significant anomalous acceleration signal still remains in the residuals after the thermal recoil force has been properly accounted for. Results of this meticulous study will be published soon.