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Ulrika Magnea

Publications and source records attributed to Ulrika Magnea.

5 recordsLinked to original sources

Random matrices beyond the Cartan classification

It is known that hermitean random matrix ensembles can be identified with symmetric coset spaces of Lie groups, or else with tangent spaces of the same. This results in a classification of random matrix ensembles as well as applications in practical calculations of physical observables. In this paper we show that a large number of non-hermitean random matrix ensembles defined by physically motivated symmetries - chiral symmetry, time reversal invariance, space rotation invariance, particle-hole symmetry, or different reality conditions - can likewise be identified with symmetric spaces. We give explicit representations of the random matrix ensembles identified with lateral algebra subspaces, and of the corresponding symmetric subalgebras spanning the group of invariance. Among the ensembles listed we identify as special cases all the hermitean ensembles identified with Cartan classes of symmetric spaces and the three Ginibre ensembles with complex eigenvalues.

math-ph

Lectures on random matrix theory and symmetric spaces

In these lectures we discuss some elementary concepts in connection with the theory of symmetric spaces applied to ensembles of random matrices. We review how the relationship between random matrix theory and symmetric spaces can be used in some physical contexts.

math-ph

An introduction to symmetric spaces

Recently, the theory of symmetric spaces has come to play an increased role in the physics of integrable systems and in quantum transport problems. In addition, it provides a classification of random matrix theories. In this paper we give a self--contained introduction to symmetric spaces and their main characteristics. We take an algebraic approach; therefore it is not necessary to know almost anything about differential geometry to be able to follow the outline.

cond-mat

The orthogonal ensemble of random matrices and QCD in three dimensions

We consider the parity-invariant Dirac operator with a mass term in three-dimensional QCD for $N_c=2$ and quarks in the fundamental representation. We show that there exists a basis in which the matrix elements of the Euclidean Dirac operator are real. Assuming there is spontaneous breaking of flavor and/or parity, we read off from the fermionic action the flavor symmetry-breaking pattern $Sp(4N_f) \to Sp(2N_f) \times Sp(2N_f)$ that might occur in such a theory. We then construct a random matrix theory with the same global symmetries as two-color QCD$_3$ with fundamental fermions and derive from here the finite-volume partition function for the latter in the static limit. The expected symmetry breaking pattern is confirmed by the explicit calculation in random matrix theory. We also derive the first Leutwyler-Smilga-like sum rule for the eigenvalues of the Dirac operator.

hep-th