The cardinality of ℝⁿ is the same though for all finite n (same for ℕ, ℤ, or ℚ), so it doesn’t make that much of a difference. ;)

Ah! I see I've found a cosmologist!

Why are you not using normal letters to denote Rⁿ and N, Z or Q?

They're using the typical symbols for denoting those sets, which are fancier than the symbols used for mere variables. One only resorts to using basic letters if the usual symbols aren't available.

https://en.wikipedia.org/wiki/Real_number

Isn't it much more work to find those symbols and copy and paste them though?

More work for the author, but nicer for the reader, and makes it more self-explanatory which sets are meant. The latter is what I cared about.

Also, if you’re on desktop with a suitably configured Compose key, it’s actually simple to type (Compose I R for example), no need for copy&paste.

Interesting, thanks.

I was not talking about the physicality of reality. They were saying people enter or see into another dimension.

I have no idea what "another dimension" means if we're not talking about degrees of freedom.

https://www.youtube.com/watch?v=qORYO0atB6g