King Kakudmi & Revati visit Brahmā’s realm — return after 27 yuga cycles (Bhāgavata Purāṇa 9.8.26–28). King Muchukunda sleeps for an age; awakens after Manvantaras have passed (Mahābhārata 3.186). Vimānas described in Mahābhārata & Rāmāyaṇa — flying chariots with propulsion and weapon systems Brahmāstra & other astra weaponry reminiscent of nuclear weapons (Mahābhārata) Maya Dānava’s flying palaces & mechanical beings → engineered automatons and anti-gravity craft. Brahma’s day and night cycles — billions of human years each → cosmic time loops / cyclic universe.