SpaceWe are about to hear echoes in the fabric of space for the first time Gravitational waves can be lensed by massive galaxies so that they repeat, like an echo. Scientists are now readying to snare their first one and explore the cosmic secrets it holds Features
MathematicsThe mathematician who worked out how to time travel Mathematics suggested that time travel is physically possible – and Kurt Gödel proved it. Mathematician Karl Sigmund explains how the polymath did it News