Most private firms have strict policies about salaries: Workers aren’t allowed to know how much money they make compared to their peers. But that’s an unrealistic and outdated notion, especially with so much information available online. Pay inequality is a persistent problem that is getting more exposure than ever before. In her latest research, Wharton management professor Claudine Gartenberg examines how inequality affects individual workers and entire companies. Her findings are outlined in three papers: “Pay Inequality and Reductions in Corporate Scope,” co-authored with Wharton management professor Emilie Feldman and Julie Wulf of the National Bureau of Economic Research; “Islands of Equality: Competition and Pay Inequality within and across Firm Boundaries,” co-authored with Wulf, and “Pay Harmony? Social Comparison and Performance Compensation in Multibusiness Firms,” co-authored with Wulf. She spoke to Knowledge at Wharton about why top-tier managers need to pay more attention to this issue.…