http://www.physorg.com/news/2011-08-dark-illusion-quantum-vacuum.html
(PhysOrg.com) -- One of the biggest unsolved problems in astrophysics is that galaxies and galaxy clusters rotate faster than expected, given the amount of existing baryonic (normal) matter. The fast orbits require a larger central mass than the nearby stars, dust, and other baryonic objects can provide, leading scientists to propose that every galaxy resides in a halo of (as yet undetectable) dark matter made of non-baryonic particles. As one of many scientists who have become somewhat skeptical of dark matter, CERN physicist Dragan Slavkov Hajdukovic has proposed that the illusion of dark matter may be caused by the gravitational polarization of the quantum vacuum. “The key message of my paper is that dark matter may not exist and that phenomena attributed to dark matter may be explained by the gravitational polarization of the quantum vacuum,” Hajdukovic told PhysOrg.com. “The future experiments and observations will reveal if my results are only (surprising) numerical coincidences or an embryo of a new scientific revolution.” Like his previous study featured on PhysOrg http://www.physorg.com/news/2011-07-big-quick-conversion-antimatter.html about a cyclic universe successively dominated by matter and antimatter, Hajdukovic’s paper on a dark matter alternative is also an attempt to understand cosmological phenomena without assuming the existence of unknown forms of matter and energy, or of unknown mechanisms for inflation and matter-antimatter asymmetry. In the case of the fast rotational curves of galaxies, he explains that there are currently two schools of understanding the phenomenon. “The first school invokes the existence of dark matter, while the second school invokes modification of our law of gravity,” he said. “I suggest a third way, without introducing dark matter and without modification of the law of gravity.” His ideas (like those in the previous paper) rest on the key hypothesis that matter and antimatter are gravitationally repulsive, which is due to the fact that particles and antiparticles have gravitational charge of opposite sign. (Though like matter, antimatter is gravitationally attractive with itself.) Currently, it is not known whether matter and antimatter are gravitationally repulsive, although a few experiments (most notably, the AEGIS experiment at CERN) are testing related concepts. “Concerning gravity, mainstream physics assumes that there is only one gravitational charge (identified with the inertial mass) while I have assumed that, as in the case of electromagnetic interactions, there are two gravitational charges: positive gravitational charge for matter and negative gravitational charge for antimatter,” Hajdukovic explained. <end>