The spectral gap is one of the most important physical properties of a quantum many-body system, determining much of its low-energy physics. Gapped systems exhibit non-critical behaviour (for example, ...

This is a preview. Log in through your library . Journal Information The Journal of Symbolic Logic (JSL) was founded in 1936 and it has become the leading research journal in the field. It is issued ...

This course gives an introduction to the mathematical foundations of computation. The course will look at Turing machines, universal computation, the Church-Turing thesis, the halting problem and ...

This article was published in Scientific American’s former blog network and reflects the views of the author, not necessarily those of Scientific American Julia Robinson was born on December 8, 1919.