The Hindu cosmology and timeline is the closest to modern scientific timelinesand even more which might indicate that the Big Bang is not the beginning of everything, but just the start of the present cycle preceded by an infinite number of universes and to be followed by another infinite number of universes
The universe is cyclically created and destroyed in the timespan of 8.64 billion years
From the viewpoint of Hinduism, heaven and hell are merely different worlds, bound by time, space, and causality. According to Hinduism, desires are responsible for a person’s embodiment. Some of these desires can best be fulfilled in a human body, and some in an animal or a celestial body. Accordingly, a soul assumes a body determined by its unfulfilled desires and the results of its past actions. An animal or a celestial body is for reaping the results of past karma, not for performing actions to acquire a new body. Performance of karma to effect any change of life is possible only in a human body, because only human beings do good or evil consciously. Human birth is therefore a great privilege, for in a human body alone can one attain the supreme goal of life. Thus, in search of eternal happiness and immortality, the apparent soul is born again and again in different bodies, only to discover in the end that immortality can never be attained through fulfillment of desires. The soul then practices discrimination between the real and the unreal, attains desirelessness, and finally realizes its immortal nature. Affirming this fact, the Katha Upanishad says: “When all the desires that dwell in the heart fall away, then the mortal becomes immortal and here attains Brahman.”
is seen as a transitory place for righteous souls who have performed good deeds in their lives but are not yet ready to attain moksha, or elevation to Vaikunta
It is a heaven where the righteous live in a paradise before their next incarnation. During each pralaya, the great dissolution, the first three realms, Bhu loka (Earth), Bhuvar loka, Swarga loka, are destroyed.
constitute Brahmaloka, or the highest heaven, where fortunate souls repair after death and enjoy spiritual communion with the personal God, and at the end of the cycle attain liberation, though a few return to earth again.
is the lowest of the seven nether worlds, is the realm where wicked souls sojourn after death and reap the results of their unrighteous actions on earth.
is ruled by Bala – a son of Maya – who possesses mystical powers. By one yawn, Bala created three types of women – svairiṇīs (“self-willed”), who like to marry men from their own group; kāmiṇīs (“lustful”), who marry men from any group, and the puḿścalīs (“those who wholly give themselves up”), who keep changing their partners. When a man enters Atala, these women enchant him and serve him an intoxicating, cannabis drink that induces sexual energy in the man. Then, these women enjoy sexual play with the traveller, who feels to be stronger than ten thousand elephants and forgets impending death.
is ruled by the god Hara-Bhava – a form of Shiva, who dwells with attendant ganas including ghosts and goblins as the master of gold mines. Here he enjoys sexual union with his consort Bhavani and their sexual fluids flow as river Hataki here. When fire – fanned by wind – drinks from this river, it spits the water out as a type of gold called Hataka. The residents of this realm are adorned with gold from this region
is the kingdom of the pious demon king Mahabali. The dwarf Avatar of Vishnu, Vamanatricked Bali – who had conquered the three worlds – by begging for three paces of land and acquired the three worlds in his three paces. Vamana pushed Bali to Sutala, but when Bali surrendered to Vishnu and gave away all his belongings to him, Vishnu in return made Bali, richer than Indra, the god-king of heaven. Bali still prays to Vishnu in this realm.
is the home of the demons – Danavas and Daityas, who are mighty but cruel. They are the eternal foes of Devas(the gods). They live in holes like serpents.
is the realm of the demon-architect Maya, who is well-versed in sorcery. Shiva, as Tripurantaka, destroyed the three cities of Maya but was later pleased with Maya and gave him this realm and promised to protect him.
is the abode of many-hooded Nagas (serpents) – the sons of Kadru, headed by the Krodhavasha (Irascible) band of Kuhaka, Taksshaka, Kaliya and Sushena. They live here with their families in peace but always fear Garuda, the eagle-man.
Patala or Nagaloka =
is the lowest realm and the region of the Nagas, ruled by Vasuki. Here live several Nagas with many hoods. Each of their hood is decorated by a jewel, the light of which illuminates this realm.
The world of Mahah is located between Brahmaloka and Bhuh, Bhuuah, and Swah.