Bridge by Lauren Beukes

Bridge's maverick scientist mother Jo is dead. Now she's examining everything Jo left behind. Which is when she finds her big secret. Is it a drug? A gateway to other worlds? Jo believed so. Bridge is desperate to see her mother again. Will do anything, risk anything. Including search for her in those other realities. What she doesn't know is that others are after Jo's secret. And some believe anyone it touches must be destroyed. Bridge? She just wants to find her mom ...