Sri Chinmoy: The physical or biological power and the spiritual power can go together. But if we see light or an aura around somebody's head, this is definitely spiritual light. It is not radiating on the physical plane; it is something spiritual. Each person has an aura. Some people have one, some people have two, some people have many. As you practise the spiritual life, you get many, many auras.
Similarly, each of us has an inner sun. Sri Ramakrishna saw one inner sun in Keshab Sen, a sage from Bengal, but in Swami Vivekananda he saw eighteen inner suns. Spiritual people who are very highly advanced or who are spiritual Masters have much more light around their heads than ordinary people. But it is not from the physical that this light or aura is coming. It is coming from beyond the physical.