Do geons really exist?
John Archibald Wheeler, a physicist who coined many terms. You may have heard of some of them: wormhole, black hole, quantum foam and geon, wait, geon?
Wheeler was one of those people who seemed to be in the right place at the right time. After studying physics, he collaborated with Albert Einstein in his later years. Einstein spent a lot of time creating a unified field theory, the “theory of everything”, which many today reject, but even those who do not reject his theory do not believe that Einstein could work on it, having the data that he had at that time.
Wheeler continued the work of Einstein and seems to have used it well. He had tons of ideas, some of them filled the physical Universe, and some populated science fiction worlds from stories. He came up with the conditions for a black hole and a wormhole.
He also coined the term "geon." Geon is difficult to find in reality, and he would not have helped the crew of the starship to move to the edge of the Universe, so he did not receive such approval in the press as other ideas of Wheeler. Basically, it is an electromagnetic wave, and very energetic. As Einstein showed, mass and energy are equivalent, and this means that energy must gravitate in the same way as mass does. In Wheeler’s mind, a certain amount of energy, all in one place, could produce enough gravity to keep itself in a certain volume. Thus, a geon is a wave of energy stored in one “ball” and in one volume of space.
There is much debate about geons, in particular, about their stability. Stable or unstable, is that the question? Gravity, Einstein showed, radiates outward no faster than the speed of light. If a geon emits gravitational waves, then it must lose energy. One day, he will lose enough energy, lose the force of gravity necessary to hold it in a certain volume, and dissolve. So geon can be a very ephemeral thing.