Open AccessModelling the Pioneer anomaly as modified inertia
Author(s) -
McCulloch M. E.
Publication year - 2007
Publication title -
monthly notices of the royal astronomical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.058
H-Index - 383
eISSN - 1365-2966
pISSN - 0035-8711
DOI - 10.1111/j.1365-2966.2007.11433.x
Subject(s) - physics , unruh effect , anomaly (physics) , acceleration , inertia , inertial frame of reference , hubble's law , astrophysics , cosmology , classical mechanics , quantum , dark energy , quantum mechanics
This paper proposes an explanation for the Pioneer anomaly: an unexplained Sunward acceleration of 8.74 ± 1.33 × 10 −10 m s −2 seen in the behaviour of the Pioneer probes. Two hypotheses are made. (1) Inertia is a reaction to Unruh radiation and (2) this reaction is weaker for low accelerations because some wavelengths in the Unruh spectrum do not fit within a limiting scale (twice the Hubble distance) and are disallowed: a process similar to the Casimir effect. When these ideas are used to model the Pioneer crafts' trajectories, there is a slight reduction in their inertial mass, causing an anomalous Sunward acceleration of 6.9 ± 3.5 × 10 −10 m s −2 which agrees within error bars with the observed Pioneer anomaly beyond 10 au from the Sun. This new scheme is appealingly simple and does not require adjustable parameters. However, it also predicts an anomaly within 10 au of the Sun, which has not been observed. Various observational tests for the idea are proposed.