Gauge status of the additive constant in the potential two-point function
Establish whether the freedom to add an arbitrary constant to the weak-field potential two-point function G(x,x′) to ensure positive semidefiniteness is purely a gauge choice, and elucidate the resulting physical implications for measurable acceleration variances and spectral densities in tabletop and astrophysical settings.
References
While Eq. eq:freedom is not postive semidefinite, for any finite range of $x,x'$ one can add a large enough constant to insures that~eq:freedom is positive semi-definite. The constant does not effect the variance in acceleration which is the physically meaningful quantity. We conjecture that this is thus a gauge choice, but a fuller understanding of the physical implications is required.
— Anomalous contribution to galactic rotation curves due to stochastic spacetime
(2402.19459 - Oppenheim et al., 29 Feb 2024) in Appendix: Section “Comparison with tabletop experiments”