The first two digital revolutions — computing and communications — transformed society. Now comes the third, which is fabrication, argues the new book, Designing Reality. The authors say that computerized fabrication such as 3-D  printing is the beginning of a trend to change data into objects. But like any revolution, not all populations will benefit equally. The book, which is aimed at helping people prepare for the next tech wave, was written by three brothers: Alan Gershenfeld, president of E-Line Media and former chairman of Games for Change; Joel Cutcher-Gershenfeld, a professor at Brandeis University; and Neil Gershenfeld, who heads The Center for Bits and Atoms at MIT. Alan Gerhsenfeld and Cutcher-Gershenfeld talked about their book on the  Knowledge at Wharton show, which airs on SiriusXM channel 111.  (Listen to the full podcast using the player at the top of this page.) An edited transcript of the conversation follows.…