Observational Constraints on the Completeness of Space near Astrophysical Objects

TL;DR

This paper uses astronomical observations of Mercury's orbit and a double pulsar system to place constraints on the possible topological deficit angle in space, finding bounds that are consistent with a nearly complete space topology.

Contribution

It provides new observational bounds on the deficit angle in space topology using solar system and pulsar data, extending constraints to different astrophysical environments.

Findings

Solar system bound: 0<(1-w)<10^(-9) at 95% confidence

Pulsar system bound: 0<(1-w)<2.4*10^(-8) at 95% confidence

Future data may tighten these constraints significantly.

Abstract

We consider the observational effects of a deficit angle, w, in the topology of the solar system and in the 'double pulsar' system PSR J0737-3039A/B. Using observations of the perihelion precession of Mercury, and the gravitational deflection of light due to the Sun, we constrain the magnitude of such a deficit angle in the solar system to be 2*pi*(1-w), with 0<(1-w)<10^(-9) at 95% confidence. We calculate the effects of a deficit angle on the periastron advance, geodetic precession rate and inclination angle of the double pulsar system and use the observational data to obtain the constraint 0<(1-w)<2.4*10^(-8) at 95% confidence. Although this result is weaker than the solar system bound, it is in a very different physical environment, where accumulating data is likely to lead to tighter constraints in the future.