Antimatter Gravity and the Results of the ALPHA-g Experiment
arXiv:2503.03846 · doi:10.1002/andp.202300519
Abstract
By combining general relativity and CPT symmetry, the theory of CPT gravity predicts gravitational repulsion between matter and CPT-transformed matter, i.e. antimatter inhabiting an inverted space-time. Such repulsive gravity turned out to be an excellent candidate for explaining the accelerated expansion of the Universe, without the need for dark energy. The recent results of the ALPHA-g experiment, which show gravitational attraction between antihydrogen atoms and the Earth, seem to undermine this success in the cosmological field. Analyzing the above theory, we find two solutions that can be consistent with the experimental results, while preserving the large-scale gravitational repulsion. The first highlights how repulsive gravity can be the result of the interaction with an inverted space-time, but occupied by matter and not antimatter, and therefore the antimatter present in our space-time has no reason to exhibit gravitational repulsion. The second retains the original CPT transformation, resulting in repulsive gravity between matter and antimatter, but with the caveat that antimatter immersed in our space-time cannot exhibit the PT transformation which is the cause of the repulsion. Finally, it is shown that, in a Newtonian approximation of the geodesic equation, time reversal is not a necessary operation for repulsive gravity, therefore opening the possibility of an expanding cosmos with a single time direction.
arXiv commentThis is the pre-peer-reviewed version of the article published in Annalen der Physik, which is downloadable in Open Access at https://doi.org/10.1002/andp.202300519
References in corpus (23)
- Observational Evidence from Supernovae for an Accelerating Universe and a Cosmological Constant
- Measurements of Omega and Lambda from 42 High-Redshift Supernovae
- 4D Gravity on a Brane in 5D Minkowski Space
- Is Cosmic Speed-Up Due to New Gravitational Physics?
- Reconciling dark energy models with f(R) theories
- Clues from nearby galaxies to a better theory of cosmic evolution
- Marginal evidence for cosmic acceleration from Type Ia supernovae
- Perturbations in a coupled scalar field cosmology
- CPT symmetry and antimatter gravity in general relativity
- Introducing the Dirac-Milne universe
- Is cosmic acceleration proven by local cosmological probes?
- Gravitational lensing shear by an exotic lens object with negative convergence or negative mass
- Testing Yukawa-like potentials from f(R)-gravity in elliptical galaxies
- Opposite Thermodynamic Arrows of Time
- Is dark matter an illusion created by the gravitational polarization of the quantum vacuum?
- Virtual gravitational dipoles: The key for the understanding of the Universe?
- On the nature of dark energy: the lattice Universe
- Microlensed image centroid motions by an exotic lens object with negative convergence or negative mass
- Gravity, antimatter and the Dirac-Milne universe
- "Dark energy" in the Local Void
- Cosmology under Milne's shadow
- On the gravitational field of a point-like body immersed in quantum vacuum
- The matter-antimatter interpretation of Kerr spacetime