Earth-orbit bounds on screened dark energy

TL;DR

This work probes screened dark energy models—chameleon, symmetron, and dilaton—by computing leading 1PN corrections to three Earth-orbit observables and mapping them onto model parameter spaces. Through Gravity Probe B, LAGEOS-2, and a projected Sagnac timing setup, it derives new Earth-based bounds that, in several cases, compete with or surpass solar-system constraints, especially given the Earth’s shallower potential relative to the Sun. The results show Sagnac-type measurements as particularly powerful for chameleon scenarios, while LAGEOS-2 provides the strongest constraints for symmetron and dilaton models, highlighting the value of low-density space-based tests. The findings motivate future improvements in geodetic data analyses and clock-based Sagnac experiments, potentially closing remaining regions of parameter space for these screened theories.

Abstract

We test dark-energy-motivated screening mechanisms with near-Earth space-based measurements. Within a post-Newtonian treatment, we compute leading corrections to three observables, namely geodetic precession (Gravity Probe B), pericenter advance of LAGEOS-2, and Sagnac time delay in a prospective orbital configuration. We then map these corrections to bounds on chameleon, symmetron, and dilaton models. LAGEOS-2 data yield the strongest Earth-orbit limits for symmetron and dilaton models, while a prospective Sagnac setup provides the tightest constraint for chameleons. These results highlight the relevance of low-density, space-based experiments as sensitive probes of screened dark energy and exclude previously allowed regions of parameter space.

Figures (6)

• Figure 1: GP-B schematic and geometry of the geodetic and frame-dragging effects. Adapted from Fig. 1 in Ref. Everitt2011.
• Figure 2: Secular pericenter precession of an Earth-orbiting satellite.
• Figure 3: Schematic of a Sagnac experiment around Earth. We denote by $R_{\text{orb}}$ the radius of the circular path, by $\Omega$ the satellite’s angular speed, and by $\omega_{+}$ and $\omega_{-}$ the angular velocities of the co- and counter-rotating light beams.
• Figure 4: Constraints on the chameleon parameter space in the plane $(n, \beta_m)$ for $\Lambda = \Lambda_{\text{DE}} \sim 2.4\,\text{meV}$. The shaded (colored) regions indicate the portions of parameter space that are excluded by the different experiments considered: GP-B, LAGEOS-2, and the Sagnac setup, together with the Solar System light-deflection constraints derived from the Cassini experiment Zhang2016. By assuming the sensitivities of current space-qualified clocks (see the discussion above Eq. \ref{['eq:deviationSagnac']} for further details), Sagnac experiment provides the most stringent bound among Earth-orbit tests. In this case, we assume a satellite orbit radius $R_{\text{orb}}$ corresponding to an altitude of approximately $500\,\text{km}$ above Earth’s surface.
• Figure 5: Constraints on the symmetron parameter space in the plane $(\log_{10}(M_{\text{sym}}/\mathrm{GeV}),\log_{10}(\lambda))$ with the tachyonic mass fixed to $\mu=1\,\mathrm{meV}$ (left panel) and $\mu=1\,\mathrm{eV}$ (right panel). Both axes are shown on a base-10 logarithmic scale. Shaded (colored) regions indicate exclusions from GP-B, LAGEOS-2, the orbital Sagnac setup, and, for comparison, the bounds from Mercury’s perihelion shift Zhang2016. For the Sagnac projection we assume an orbital radius $R_{\mathrm{orb}}$ corresponding to an altitude of approximately $500\,\mathrm{km}$.