In an article on NewScientist, there are two proposals to detect whether antimatter is gravitationally repulsive to matter, or not. Fermilab in Chicago and CERN in Switzerland are proposing experiments, which they hope will detect the gravitational relationship of matter and antimatter.
The Aether Physics Model induces that matter and antimatter must be gravitationally repulsive. This can be determined from the observation that two photons can join together to produce a positron-electron pair. Positrons and electrons are massive particles with the same mass, but opposite spins. The two photons must be the source of the angular momentum needed to produce these two particles, which means the right and left spin must already exist in the photon in quantities equal to half the mass of the electron and half the mass of the positron.
Standard Model theory denies the existence of Aether. Yet, the Aether provides the quantifiable structure needed for understanding how electron and positron angular momentum can coexist in the same photon.
The photon and Aether structures are geometrically identical. If the positron and electron angular momentum coexist in an Aether unit, and the photon has zero mass, then in order for two photons to produce a positron-electron pair the positron and electron masses must be opposite and therefore be gravitationally repulsive.
Further evidence of antimatter repulsiveness is observed in positron clouds drifting through space. The only way positron clouds could congregate in the wide spaces is if they were repelled from normal matter at great distances. Although gravity is a weak force, it works at great distances.
This is one experiment I would like Fermilab and CERN to get funding for. Not only could it provide strong evidence in favor of the Aether Physics Model, but it could also reveal a great weakness of General Relativity theory.