383 citations · 1.1k across the 18 of their papers we have counts for
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Symmetric polynomials in information theory: entropy and subentropy
Richard Jozsa, Graeme Mitchison
Entropy and other fundamental quantities of information theory are customarily expressed and manipulated as functions of probabilities. Here we study the entropy H and subentropy Q…
Entropy, subentropy and the elementary symmetric functions
Richard Jozsa, Graeme Mitchison
We use complex contour integral techniques to study the entropy H and subentropy Q as functions of the elementary symmetric polynomials, revealing a series of striking properties.…
On exact quantum query complexity
Ashley Montanaro, Richard Jozsa, Graeme Mitchison
We present several families of total boolean functions which have exact quantum query complexity which is a constant multiple (between 1/2 and 2/3) of their classical query complex…
The hierarchical structure of local unitary invariants
Graeme Mitchison
Local unitary invariants allow one to test whether multipartite states are equivalent up to local basis changes. Equivalently, they specify the geometry of the "orbit space" obtain…
Cumulants and the moment algebra: tools for analysing weak measurements
Johan Aberg, Graeme Mitchison
Recently it has been shown that cumulants significantly simplify the analysis of multipartite weak measurements. Here we consider the mathematical structure that underlies this, an…
Weak measurement takes a simple form for cumulants
Graeme Mitchison
A weak measurement on a system is made by coupling a pointer weakly to the system and then measuring the position of the pointer. If the initial wavefunction for the pointer is rea…