a survey on upanishadic cosmogonical myths

this article has been dedicated to explain radical concepts of cosmogonical myths at one of the main periods of hindu thougth i.e upanishadic period and the most important text of this era i.e the upanishads(800-500 bce) have been examined. in regards to background of cosmogonical ideas at earlier eras, from vedic period to brahmanas, we can say that theme upanishads in this respect have been existed already in the vedas. but in the upanishads the ideas such as monotheism, pantheism, emanation of many from one, have been explicitly discussed. and there are debates about brahman and atman which are both the cause of creation & have identified with it. moreover atman & brahman have been identified with each other in this case they are also the cause of creation.