Is the Cosmos really all it is, or ever was, or ever will be?

Question

Taken from "The Cosmos" by Carl Sagan.

Answer 1

Only if you can't think outside the box!

Do you not know? Have you not heard? Yahweh is the everlasting God, the Creator of the whole earth. He never grows faint or weary; there is no limit to His understanding.
Isaiah 40:28

Answer 2

In that personal abode of the Lord, the material modes of ignorance and passion do not prevail, nor is there any of their influence in goodness. There is no predominance of the influence of time, so what to speak of the illusory, external energy; it cannot enter that region. Without discrimination, both the demigods and the demons worship the Lord as devotees.
PURPORT
The kingdom of God, or the atmosphere of the Vaikuntha nature, which is called the tripäd-vibhüti, is three times bigger than the material universes and is described here, as also in the Bhagavad-gitä, in a nutshell. This universe, containing billions of stars and planets, is one of the billions of such universes clustered together within the compass of the mahat-tattva. And all these millions and billions of universes combined together constitute only one fourth of the magnitude of the whole creation of the Lord. There is the spiritual sky also; beyond this sky are the spiritual planets under the names of Vaikuntha, and all of them constitute three fourths of the entire creation of the Lord. God's creations are always innumerable. Even the leaves of a tree cannot be counted by a man, nor can the hairs on his head. However, foolish men are puffed up with the idea of becoming God Himself, though unable to create a hair of their own bodies. Man may discover so many wonderful vehicles of journey, but even if he reaches the moon by his much advertised spacecraft, he cannot remain there. The sane man, therefore, without being puffed up, as if he were the God of the universe, abides by the instructions of the Vedic literature, the easiest way to acquire knowledge in transcendence. So let us know through the authority of Srémad-Bhägavatam of the nature and constitution of the transcendental world beyond the material sky. In that sky the material qualities, especially the modes of ignorance and passion, are completely absent. The mode of ignorance influences a living entity to the habit of lust and hankering, and this means that in the Vaikunthalokas the living entities are free from these two things. As confirmed in the Bhagavad-gitä, in the brahma-bhüta [SB 4.30.20] stage of life one becomes free from hankering and lamentation. Therefore the conclusion is that the inhabitants of the Vaikuntha planets are all brahma-bhüta living entities, as distinguished from the mundane creatures who are all compact in hankering and lamentation. When one is not in the modes of ignorance and passion, one is supposed to be situated in the mode of goodness in the material world. Goodness in the material world also at times becomes contaminated by touches of the modes of passion and ignorance. In the Vaikunthaloka, it is unalloyed goodness only.

Answer 3

Depends what you mean by 'Cosmos'.
The Creator is all there is - and our 'cosmos' is a part of It.

Answer 4

Depending on how you define 'Cosmos', yes.

Answer 5

No