What is sol niger within?

Sol niger is a Latin phrase meaning "black sun." It is a symbolic representation of the "shadow" or "dark side" of the psyche. In alchemy, it represents the process of transformation and transmutation of the self. Sol niger is also associated with the concept of the unconscious, and the process of confronting and integrating one's shadow self. This concept is often explored in psychological and spiritual teachings, as a means of facilitating personal growth and development.