7,050 research outputs found
Non Abelian structures and the geometric phase of entangled qudits
In this work, we address some important topological and algebraic aspects of
two-qudit states evolving under local unitary operations. The projective
invariant subspaces and evolutions are connected with the common elements
characterizing the su(d) Lie algebra and their representations. In particular,
the roots and weights turn out to be natural quantities to parametrize cyclic
evolutions and fractional phases. This framework is then used to recast the
coset contribution to the geometric phase in a form that generalizes the usual
monopole-like formula for a single qubit.Comment: 22 pages, LaTe
Fractional topological phase for entangled qudits
We investigate the topological structure of entangled qudits under unitary
local operations. Different sectors are identified in the evolution, and their
geometrical and topological aspects are analyzed. The geometric phase is
explicitly calculated in terms of the concurrence. As a main result, we predict
a fractional topological phase for cyclic evolutions in the multiply connected
space of maximally entangled states.Comment: REVTex, 4 page
Fraser of cryptophthalmosis syndrome: A case report
Fraser or cryptophthalmos syndrome is a rare autosomal recessive disorder characterized by major features such as cryptophthalmos, syndactyly, and abnormal genitalia. Consanguinity is reported in 15-24.8% of the cases. The diagnosis of this syndrome can be made on clinical examination; therefore we present the clinical findings of a rare case of Fraser syndrome in a female infant
DBI Realizations of the Pseudo-Conformal Universe and Galilean Genesis Scenarios
The pseudo-conformal universe is an alternative to inflation in which the
early universe is described by a conformal field theory on approximately flat
space-time. The fields develop time-dependent expectation values, spontaneously
breaking the conformal symmetries to a de Sitter subalgebra, and fields of
conformal weight zero acquire a scale invariant spectrum of perturbations. In
this paper, we show that the pseudo-conformal scenario can be naturally
realized within theories that would ordinarily be of interest for DBI
inflation, such as the world-volume theory of a probe brane in an AdS bulk
space-time. In this approach, the weight zero spectator field can be associated
with a geometric flat direction in the bulk, and its scale invariance is
protected by a shift symmetry.Comment: 34 page
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