This is not a new theory. There are always several theories about these things. The original theory of the solar system is that it formed from a nebula of gas and fine dust. The dust became electrically charged, and electro-magnetic force then assisted gravity in the formation of the sun and planets. Gravity by itself is not strong enough. Large objects would not work; it requires dust.
It was thought that the Earth and Moon formed together just as other planets have moons too. However, it was found from the analysis of moon rocks that the Moon is much higher in titanium than the Earth so it is doubtful that they formed together.
In the early solar system there was a fifth planet where the asteroid belt is now. Using calculations based on Bodes Law early astronomers thought it should be there and called it Krypton for hidden. This would have been a gas giant planet about the size of Saturn and have its own moons. This planet exploded with debris flying away in all directions. The comets falling back from all directions in the sky are the remains of this planet. The asteroids are fragments of some of its moons.
However two moons remained intact and orbiting each other they moved toward the Sun and eventually did a dance with the earth. The interaction between the three objects allowed one to be captured by earth's gravity while the other was ejected. The Earth gained a little speed in the process and there was no collision as another theory would have happen. The most heavily cratered side of the Moon was facing Krypton when it exploded.
The other stray moon was sent toward the Sun where it may have also encountered Venus, but in any event went into an elliptical orbit and we now call it Mercury.
Dark Matter Missing Planets & New Comets: Paradoxes Resolved Origins Illuminated, By Tom Van Flandern, C 1993, North Atlantic Books, Berkeley
The Cosmic War: Interplanetary Warfare, Modern Physics and Ancient Texts, By Joseph P. Farrell, C 2007, Adventures Unlimited Press.