Bharatiya Shakti Sadhna   (Swaroop Aur Siddhant)  :-
An authentic book on the Worship of Indian Goddeses Writen by Dr. Shyamakant Dwivedi.
In the 'birth' and 'spreading' of the universe, the power of grace remains active and in its 'mahapralaya', the power of oblivion remains active.  It is the prelude of the Agam that when the harmony state of Shiva Shakti is disturbed, 'for unknown reasons' Shakti gets a sense of independence and she comes out separated from the heart of Shiva.  This form of manifestation and expansion of the universe is that of 'subtle creation', it has five elements and three gunas, and lacks time and space divided into the triad of 'Kaal' and 'Kshetra'.  The knowledge tradition interprets it as 'Para Prakriti'.