The short answer is no.  You can use the stainless steel nuts and bolts included in the kit without glue.  If you don't want the nuts and bolts, we still advise you to use the nuts and bolts when you glue, and then remove them once the glue has cured.  As for not using either glue or nuts and bolts, don't do it.  The hubs are designed to fit snugly, but it will only be a matter of time before the structure starts to work its way apart. Gluing the joints  precludes taking the dome apart and rebuilding it somewhere else, so think of that before you build. Bolting it doesn’t take that much time, and it definitely won’t work it’s way apart if you tighten the nuts firmly. You could also use cotter keys, or zip ties, or any other manner of connector, but if there’s going to be people around it, don’t risk it coming apart.