PhysicsThe string-loop theory that might finally untangle the universeCould two rival theories of the make-up of the cosmos really be the same thing? Pulling at the threads could reveal a deeper realityFeatures
HealthAnaesthesia: What really happens when the lights go outWe've used it for hundreds of years, but we still don't know how anaesthesia works. Finding out could lead to safer drugs and unlock the mystery of consciousnessFeatures