As well as being a staple of science-fiction, time travel is also the inspiration for serious (or at least semi-serious) speculation by theorists. Some have devoted themselves to working out how it might be possible in theory, if difficult in practice, to build a time machine using exotic configurations of black holes, wormholes or cosmic strings. Others have considered whether a “self-consistency principle” operates to ensure that time travellers cannot cause paradoxical situations by, for example, going back in time and murdering their own ancestors. Then there are those who have taken an experimental approach, and searched for time travellers directly. How do they do it? econ.st/1dWjdXe
Posted on: Fri, 17 Jan 2014 13:00:00 +0000