"Every time this gets tested—presumably more and more carefully—the measured force gets smaller."
Uh oh. That's a classic sign of a bogus effect. It's like physicists at Stanford trying to replicate the Pons-Fleischmann cold fusion experiment. At first, they were enthusiastic, and expected big results. They started out with the apparatus surrounded with radiation alarms in case it generated dangerous amounts of neutrons. After a while, they discovered that the effect was at most twice background radiation. Since humans have water in them and water is a neutron reflector, just moving around the equipment could produce effects at that level. Then they moved the equipment to the inside of a cube of lead bricks, to eliminate external neutrons. No more neutrons, background or otherwise.
Uh oh. That's a classic sign of a bogus effect. It's like physicists at Stanford trying to replicate the Pons-Fleischmann cold fusion experiment. At first, they were enthusiastic, and expected big results. They started out with the apparatus surrounded with radiation alarms in case it generated dangerous amounts of neutrons. After a while, they discovered that the effect was at most twice background radiation. Since humans have water in them and water is a neutron reflector, just moving around the equipment could produce effects at that level. Then they moved the equipment to the inside of a cube of lead bricks, to eliminate external neutrons. No more neutrons, background or otherwise.