Reality, aren’t thou a heartless beast! A scientist from CERN, Dragan Slavkov Hajdukovic, has claimed that dark matter may be an illusion and that its supposed effect can be explained away by more known kinds of particles simple matter particles and their corresponding anti-particles.
Option 1: Dark Matter
A startling observation in astronomy set out the hunt for an unknown form of matter, just because the gravitating effect of such hypothetical matter could explain the observations. Galactic arms were seen to be moving too rapidly for them to stay attached to the rest of the galaxy, if Newton’s law of gravitation (or even Einstein’s General Relativity) is to hold. Scientists could save the situation by postulating the presence of a large amount of non-luminous or dark matter, interacting with the rest of the Universe only by the gravitational force. No candidate for this kind of matter was proposed and people have come up with various conjectures and models. Right now, we know nothing about the composition of dark matter. It is said that dark matter comprises 23% of the known matter of the Universe. 73% is dark energy and only the rest 4% is normal matter as we know it.
Option 2: Modified Newtonian Dynamics
There was another way to resolve the puzzle modify Newton’s law of gravity. This new school of thought, called MOND or MOdified Newtonian Dynamics, said that the power law dependence of the gravitational force on distance (which is inverse-square for Newton’s law) depends on acceleration. MOND doesn’t need any dark matter. The problem with MOND is that it doesn’t seem to work at all scales of acceleration. Inherent inconsistencies prevent MOND from taking over from Newton’s gravity law.
Option 3: Gravitational polarization of Quantum Vacuum
Now, Hajdukovic postulates another possibility that space itself might be repulsive. He says that if particles and anti-particles were to repel each other gravitationally, rather than universally attract, then it would solve the problem. Vacuum could be polarized, i.e. particles and anti-particles could be created at will, governed by the Heisenberg’s Uncertainty Principle. Now, if these were to act as gravitational dipoles that repel, then the problem of amplifying gravitational fields would be solved. He gives an example of a dielectric slab inserted inside a parallel plate capacitor as an example. In this case, the electric field within the dielectric would decrease. Hajdukovic argues that, if unlike charges repelled instead of attracting, the field would increase in strength. The same, he concludes, is true with gravity.
Hajdukovic put it precisely:
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
As alien as that might sound to a reader versed in Physics, mainstream labs are actually working to find out whether anti-matter repels matter gravitationally. Primary amongst these is the AEGIS experiment at CERN.
The proposal also has a very pleasing symmetry. Gravitational force is unlike the electromagnetic force, since electromagnetic forces both repel (like charges or magnetic poles) and attract (unlike charges/magnetic poles). If Hajdukovic is right, then even gravity will have a repulsive component, but this might mean that we have to take another look at Einstein’s equations of General Relativity.
There are many issues, however. Things like gravitational lensing is explained best by assuming dark matter than without it.
Hajdukovic published his paper Is dark matter an illusion created by the gravitational polarization of the quantum vacuum?in the journal Astrophysics and Space Science.