Silvia De Bianchi is Ramón y Cajal Fellow at the Autonomous University of Barcelona, Spain. Her research interests cover epistemological questions emerging in Hermann Weyl”s scientific and philosophical works. She is interested in developing methodologies that integrate the history and philosophy of science and in exploring how models work in scientific practice. Currently, she is leading the ERC St G project PROTEUS “Paradoxes and Metaphors of Time in Early Universe(s)”. Claus Kiefer is Professor of theoretical physics at the University of Cologne. He does research on quantum gravity and the foundations of quantum theory as well as black holes and more general cosmological questions. In 2009, his essay, “Does Time Exist in Quantum Gravity?”, was awarded second prize by the Foundational Questions Institute, New York. In 2012, his essay, “Can Effects of Quantum Gravity Be Observed in the Cosmic Microwave Background?” (written together with Manuel Krämer), was awarded first prize by the Gravity Research Foundation, Wellesley Hills, USA.