A sensitive test of whether a black hole is a wormhole

A sensitive astronomical test for whether a black hole is a wormhole would be to look for perturbations in the orbit of a pulsar around the black hole, caused by a perturbing object on the other side of the wormhole. For a pulsar in an orbit like that of S2 around Sgr A* at the center of our Galaxy, the attainable mass limit on the perturber would be about 4 orders of magnitude better than derived from current observations of S2. For a stellar-mass black hole–pulsar binary, observations for 1 year could set a mass limit on a perturber more than 6 orders of magnitude better than for a pulsar orbiting Sgr A*.