mahavisnu

"This material world, it has got a date of its creation. Just like your body, it has got a date of its creation. It stays for some time, and again there is a date of its dissolution.

You take the history of everything material, either you take this body, or take this world, or take any empire or any… Just like your American country, oh, it has a date of its beginning.

Now it is staying. Now it will be, some day will come, there will be no more America.
You should know it. That means, that is nature's law. Everything. Everything is born, it stays for some time, then it is dissolute, dissolved.

That is explained in the Bhagavad-gita, bhutva bhutva praliyate (BG 8.19). All this thing, whatever material, that manifests, it comes out, it is manifested. It… Just like bubbles in the ocean. There are millions and millions bubbles created one second, and next second, it is finished."

Srila Prabhupada Lecture, San Francisco, February 6, 1967