@Gabriel I see. Of course, I am already aware that any verbal description would be incorrect and that true knowledge can only be attained through direct experience.
But if it is as you say, then I wonder if these higher ayatana states were mistakenly introduced over the several hundred years from the death of the Buddha to the first writing of the Tipitaka. Anything can be described in language, even though the accuracy wildly varies. Zen koans are a good example of this, where the language itself has become near-nonsense but nonetheless can still be understood by those with direct experience.
So if no description has been given whatsoever-- not even a koan-like one-- then that implies it has not been actually experienced.
As a counterpoint, textual corruption is just as likely to result in the loss of a truth as it is to result in the gain of a falsehood; perhapes even moreso. Maybe later sources from other teachers, such as the Visuddhimagga, will have a description of these states that had been lost from the Tipitaka. Sadly I have not yet read that book.
@NgXinZhao That makes sense. If the “universe” is of mental states instead of physical ones, then perhaps “the infinitude of space” refers to the infinitude of possible mental states? Implying a higher vantage point from which to see the infinitely many possibilities and “move” among them?
I realize too much speculation on the specifics is a good way to become entangled in wrong view, but even this general conclusion is helpful, if it is generally correct.