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Erika Meucci

Publications and source records attributed to Erika Meucci.

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Kraus operators and symmetric groups

In the contest of open quantum systems, we study a class of Kraus operators whose definition relies on the defining representation of the symmetric groups. We analyze the induced orbits as well as the limit set and the degenerate cases.

math-ph

Boundary of the Relative Outer Space

Let $\mathcal{A} = {A_1, ..., A_k}$ be a system of free factors of $F_n$. The group of relative automorphisms $\mathrm{Aut}(F_n; \mathcal{A})$ is the group given by the automorphisms of $F_n$ that restricted to each $A_i$ are conjugations by elements in $F_n$. The group of relative outer automorphisms is defined as $\mathrm{Out}(F_n; \mathcal{A}) = \mathrm{Aut}(F_n; \mathcal{A}) / \mathrm{Inn}(F_n)$, where $\mathrm{Inn (F_n)$ is the normal subgroup of $\mathrm{Aut}(F_n)$ given by all the inner automorphisms. This group acts on the relative outer space $\mathrm{CV}_n(\mathcal{A})$. We prove that the dimension of the boundary of the relative outer space is $\mathrm{dim}(\mathrm{CV}_n(\mathcal{A}))-1$.

math.GT

Relative outer automorphisms of free groups

Let $A_1,...,A_k$ be a system of free factors of $F_n$. The group of relative automorphisms $Aut(F_n;A_1,...,A_k)$ is the group given by the automorphisms of $F_n$ that restricted to each $A_i$ are conjugations by elements in $F_n$. The group of relative outer automorphisms is defined as $Out(F_n;A_1,...,A_k) = Aut(F_n;A_1,...,A_k)/Inn(F_n)$, where $Inn(F_n)$ is the normal subgroup of $Aut(F_n)$ given by all the inner automorphisms. We define a contractible space on which $Out(F_n;A_1,...,A_k)$ acts with finite stabilizers and we compute the virtual cohomological dimension of this group.

math.GT