Renowned cosmologist Brian Greene has spent a lifetime grappling with mind-bending theories and striving to understand the physical universe. And finally, he says, he was ready to tackle the search for meaning in his latest book “Until the End of Time.” In this conversation with Dan Porterfield, CEO of the Aspen Institute, the two friends of more than 30 years talk about Greene’s early education, his progression from reluctant reader to bestselling author, and his quest to understand our significance in the astoundingly vast universe. By popularizing science and demonstrating that time and space is governed by simple, elegant mathematical laws, Greene helps us understand our fleeting but utterly exquisite moment in the cosmos.