Supreme consciousness is the source of everything in this universe. i.e. Everything in the universe has been created from Supreme conscious and ultimately returns back to the same entity. The supreme consciousness is all pervasive and its wave is of infinite length (i.e. is is straight and has no wave).
But when a curve develops and the frequency of the wave increases , the fundamental factors are created. From subtle to crude they are created in the order of etherial, aerial, luminous, liquid and solid factors. This half of the cycle, transmutating from the supreme consciousness all the way to the solid factor is known as saincara.
At the solid factor stage, the solid factor develops increased density, pressure and heat within the solid unit. At a critical mass the solid unit undergoes a violent reaction due to the increased pressure and heat. The explosion known as jadasphota, transforms the solid factor back into the liquid, heat and the more subtle factors marking the beginning of the return journey back to supreme consciousness.
During the process of transformation back to the Supreme Consciousness, the solid factor gets transformed through the liquid, luminous, aerial, and etherial factors and unit minds are also created during the process. This process of transfromation from solid factor back to Supreme Consciousness is known as pratisaincara.
Under special conditions of jadasphota, a controlled reaction may occur in which a unit mind may regulate some control over the physical body. Under these conditions the unit mind will develop, evolve as a species and reproduce its physical structure. Once rationality develops within the mind of a species, that species is known as a human form. The human form is able to perform spiritual practice which allows one to complete the journey back to Supreme Consciousness.
Brahmacakra means the full cycle of creation from Supreme Consciousness, through all the different fundimental factors, through the different forms of unit consiousness and ultimately back to Supreme Consciousness.