Another book ID - multi-dimensional.

First, my apologies for making this listserv my regular hunting ground for hard-to-find obscure SF: it is impossible to resist your combined brain power, so I hope it is fun for you. Here's today's mystery:
A patron is looking for ascience fiction series, possibly published in 2000's, male author -- aboutmultiple layers of reality. Patron believes that there was a fourth/fifthdimensions of space included, an out-of-the-box innovative super universe wheresocieties can evolve to higher states of dimensions. Patron says “I cannotremember what makes the difference between the lower (us) and the higherdimensions. More of something: maybe brains, maybe spatial dimensions, maybetime dimensions…” Authors that aren’t the right match: Neil Gaiman, MichaelReaves, Victoria Schwab, Tad Williams, Kameron Hurley Hmmmm....?

David Wright http://shelftalk.spl.org/                            "Que Scay-Je?"