Properties of QBist State Spaces (2009)
Appleby, D. M., Ericsson, Asa, Fuchs, Christopher A.
Every quantum state can be represented as a probability distribution over the outcomes of an informationally complete measurement. But not all probability distributions correspond to quantum states....
Effects of the $g$-factor in semi-classical kinetic plasma theory (2008)
Brodin, Gert, Marklund, Mattias, Zamanian, Jens, Ericsson, Asa, Mana, Piero L.
A kinetic theory for spin plasmas is put forward, generalizing those of previous authors. In the model, the ordinary phase space is extended to include the spin degrees of freedom. Together with...
Mubs and Hadamards of Order Six (2006)
Bengtsson, Ingemar, Bruzda, Wojciech, Ericsson, Asa, Larsson, Jan-Ake, Tadej, Wojciech, Zyczkowski, Karol
We report on a search for mutually unbiased bases (MUBs) in 6 dimensions. We find only triplets of MUBs, and thus do not come close to the theoretical upper bound 7. However, we point out that the...
Geodesics and the best measurement for distinguishing quantum states (2005)
From statistical distinguishability of probability distributions, one can define distinguishability of quantum states. A corresponding measurement to perform, optimal in a definite sense, for...
Mutually Unbiased Bases and The Complementarity Polytope (2004)
Bengtsson, Ingemar, Ericsson, Asa
A complete set of N+1 mutually unbiased bases (MUBs) forms a convex polytope in the N^2-1 dimensional space of NxN Hermitian matrices of unit trace. As a geometrical object such a polytope exists for...
Birkhoff's polytope and unistochastic matrices, N=3 and N=4 (2004)
Bengtsson, Ingemar, Ericsson, Asa, Kus, Marek, Tadej, Wojciech, Zyczkowski, Karol
The set of bistochastic or doubly stochastic N by N matrices form a convex set called Birkhoff's polytope, that we describe in some detail. Our problem is to characterize the set of unistochastic...
How to mix a density matrix (2002)
Bengtsson, Ingemar, Ericsson, Asa
A given density matrix may be represented in many ways as a mixture of pure states. We show how any density matrix may be realized as a uniform ensemble. It has been conjectured that one may realize...
Supervisors Mats Dahllof, Uppsala University (2001)
This thesis deals with the development of an Internet chat word predictor. A word predictor guesses what word a user is typing, based on previously written words and pre x letters of the current...
Claes-Goran Lofdahl, Asa Ericsson, Klas Svensson, Emma Andreasson
Objective: To compare the healthcare costs and effects of budesonide/formoterol in a single inhaler with those of budesonide and formoterol monotherapies, and placebo, in a multinational study in...