I’d like to present a brief outline of my idea.
 

Let’s start with the structure of black holes. The modern theory assumes that black holes have electric charges. I believe that electric charge is mandatory in a black hole. It becomes totally clear once you simulate the process of matter falling into a black hole and inevitably being destroyed by its gravitational force. As the smallest possible particles the hadron substance can fall into are protons and electrons the further simulation should be performed for these particles. As a proton’s mass is nearly a thousand times bigger than an electron’s one the proportional gravity pulling on it would also be a thousand times stronger which means the event horizon being proportionally smaller for a proton than for electrons. This means that the black hole will mainly swallow protons and inevitably gain electric charge. A black hole is a natural electrical machine and is always positively charged. Therefore, the nuclei of modern galaxies, for example, are not active: strong positive charge of a supermassive black hole does not let the ionized nuclei of hydrogen (the main substance of the Universe) – i.e. protons – get into the black hole with the electric field pushing them away.
 

The situation however will be different in case if a black hole was not formed from hadron substance or antimatter: in this case the intensity of swallowing hadron substance (including hydrogen) will be moderate to high (in case if a black hole is formed of antimatter it will have negative charge).
 

This assumption – that a hadron substance black hole necessarily has charge – implies some more significant conclusions which we are not going to discuss here.

From the fact that all the black holes made of regular hadron substance are always positively charged, it follows that aside from gravitational interactions in spiral galaxies electrical one can also be of importance. It can be easily seen if we assume that besides a supermassive black hole in the center of such a galaxy there is also a variety of stellar mass black holes located in spiral arms. If the black holes are positively charged the interstellar gas and the stars will inevitably gain negative charge and will be pulled to the black holes by means of not only gravitational but also electrostatic forces. The galaxy structure will thus have a layered look – a layer of black holes will be followed by one without them. The latest discoveries in galactic cosmology confirm this suggestion – the real structure of so called spiral galaxies has in fact a concentric, layered look. The same phenomenon can be seen in dielectric materials affected by electric field, it’s called electrostatic polarization.

These are the electric forces that preserve the stability of galaxies against the existing rotation rates of stars inside them along with the gravity force. There is no dark matter! Given that, the main structural components of a galaxy, its framework are concentrically located black holes and interstellar gas around them. They keep the galaxy structure by means of both gravity force and electrical interaction. In the process of maintaining the stability of galactic structure stars play a small part being involved in gravitational interaction and taking almost no part in electrical one.
 

Besides, if we go on proceeding from these assumptions, dark matter also considerably loses the sense of its existence. All the spiral galaxies, due to positively charged black holes in them, are also positively charged which means that similar charges will push them away from each other. There’s no dark energy! However, if a galaxy or a black hole in it are made of antimatter they will subsequently be negatively charged and in this case two nearby galaxies of matter and antimatter will be attracted to one another. It is quite possible that Andromeda galaxy is made of antimatter.