Topics  >   What is a Geon?

In physics, the term "geon" refers to an entity consisting of only gravitational (GR) waves and/or electromagnetic (EM) waves which are held together in a confined region by their mutual attraction. It was first investigated in 1955 by John Wheeler, who coined the name for "gravitational-electromagnetic entity". If a geon consists of only GR waves, it is called a gravitational geon. The "electromagnetic geon" comprises only EM waves.


Figure 1. A geon can be imagined as an invisible, transparent balloon. In an ordinary balloon, gas molecules (helium, hydrogen, air, etc.) are confined by the rubber bag. In contrast, the GR and EM waves of a geon are confined in a small region exclusively by their own attraction.

Importance of Gravitational Force

GR waves are the carrier of attractive gravitational force. Their mutual attraction can easily be understood. But how can EM waves exert attractive interaction? We know that any particle with mass can experience gravitational force. Although the EM wave (photon) is massless, it has an energy of hν, where h is the Plank's constant and ν is its frequency. Through Einstein's famous equation, E = mc2, the photon also has an effective mass which can exhibit gravitational interaction. Such GR force, however, is very weak, unable to induce the formation of an "electromagnetic geon." The importance of gravitational force in the creation of a geon has been experimentally demonstrated in the study of Bose-Einstein condensates.

Bose-Einstein Condensate

A Bose–Einstein condensate (BEC) is the lowest quantum state of a group of bosons (with integer spin), such as rubidium, sodium and photons. When a gas of boson atoms are cooled to temperatures very close to absolute zero (-273.15 °C), microscopic quantum mechanical phenomena, particularly wavefunction interference, become apparent macroscopically, thus causing them to bunch together (see this article).

A geon may be regarded as a condensed state of GR and/or EM waves, much like the condensation of water molecules (H2O) into a water drop at room temperature. From this viewpoint, the electromagnetic geon is the BEC of photons (the quanta of EM waves) and the gravitational geon is the BEC of gravitons (the quanta of GR waves). As discussed above, the BEC of photons cannot be created by their own attraction. However, in 2010, Klaers et al. has managed to create the BEC of photons by confining photons in a dye-filled optical microcavity to increase the effective mass. This experimental finding demonstrates the importance of gravitational force in the creation of BEC and a geon.

The Mind Could be a Geon

The generation of action potentials is accompanied by ionic fluxes through ion channels. Physical laws dictate that any accelerating charged particle will radiate EM waves and any accelerating particle with mass should produce GR waves. An ion has both mass and charge. Before ions enter ion channels, they move slowly and randomly in the solution, with negligible acceleration. As a neuron fires, a large number of ions will pass through the channels, with strong acceleration driven by the electrochemical gradient. Because ions possess both mass and charge, their accelerated motion will produce both GR and EM waves. GR waves may play a key role in the creation of a geon. Further details are discussed in this article.


Author: Frank Lee
Last updated: 2020-09-16