The properties of quantum information in space-time can be investigated by studying operational tasks, such as ‘summoning’, in which an unknown quantum state is supplied at one point, and a call is made at another for it ...

In a model of physics taking place on a discrete set of points that approximates Minkowski space, one might perhaps expect there to be an empirically identifiable preferred frame. However, the work of Dowker et al (2004 ...

We further investigate postulates for realist versions of r elativistic quantum theory and quantum field theory in Minkowski space and other background space-t imes. According to these postulates, quantum theory is ...

Digital signatures are widely used in modern communication to guarantee authenticity and transferability of messages. The security of currently used classical schemes relies on computational assumptions. We present a quantum ...

We introduce and physically motivate the following problem in geometric combinatorics, originally inspired by analysing Bell inequalities. A grasshopper lands at a random point on a planar lawn of area 1. It then jumps ...