What a curious object. Designed by Jeremy Schafer, from his book “Origami to Astonish and Amaze”, this odd ripply mathematical conundrum hurts your brain to look at.
A fun paper manipulation first makes a nested tetrahedron, which is then accordion pleated to make the deltoid. You can then open it up like some surreal book, 4 separate rippled deltoids emerge – curious indeed.
Very heavy first week back from holidays, week 2 looks set to be worse. Folding is an interesting therapy after a busy day.