64 research outputs found
N=1 reductions of N=2 supergravity in the presence of tensor multiplets
We consider consistent truncations of N=2 supergravites in the presence of
tensor multiplets (dual to hypermultiplets) as they occur in type IIB
compactifications on Calabi--Yau orientifolds. We analyze in detail the scalar
potentials encompassing these reductions when fluxes are turned on and study
vacua of the N=1 phases.Comment: 40 pages, LaTeX, typos corrected, references adde
N=2 Supergravity Lagrangian Coupled to Tensor Multiplets with Electric and Magnetic Fluxes
We derive the full N=2 supergravity Lagrangian which contains a symplectic
invariant scalar potential in terms of electric and magnetic charges. As shown
in reference [1], the appearance of magnetic charges is allowed only if tensor
multiplets are present and a suitable Fayet-Iliopoulos term is included in the
fermion transformation laws. We generalize the procedure in the quoted
reference by adding further a Fayet-Iliopoulos term which allows the
introduction of electric charges in such a way that the potential and the
equations of motion of the theory are symplectic invariant. The theory is
further generalized to include an ordinary electric gauging and the form of the
resulting scalar potential is given.Comment: 1+34 pages LaTeX, correction of a typo in the ungauged scalar
potentia
Consistent reductions of IIB*/M* theory and de Sitter supergravity
We construct consistent non-linear Kaluza Klein reduction ansatze for a
subset of fields arising from the reduction of IIB* and M* theory on dS_5 x H^5
and dS_4 x AdS_7, respectively. These reductions yield four and
five-dimensional de Sitter supergravities, albeit with wrong sign kinetic
terms. We also demonstrate that the ansatze may be used to lift multi-centered
de Sitter black hole solutions to ten and eleven dimensions. The lifted dS_5
black holes correspond to rotating E4-branes of IIB* theory.Comment: 27 pages, late
Scherk-Schwarz Reduction of D=5 Special and Quaternionic Geometry
We give the N=2 gauged supergravity interpretation of a generic D=4, N=2
theory as it comes from generalized Scherk-Schwarz reduction of D=5, N=2
(ungauged) supergravity. We focus on the geometric aspects of the D=4 data such
as the general form of the scalar potential and masses in terms of the gauging
of a ``flat group''. Higgs and super-Higgs mechanism are discussed in some
detail.Comment: final version to be published on Class.Quant.Gra
Understanding the Ultra-Rare Disease Autosomal Dominant Leukodystrophy: an Updated Review on Morpho-Functional Alterations Found in Experimental Models
Autosomal dominant leukodystrophy (ADLD) is an ultra-rare, slowly progressive, and fatal neurodegenerative disorder associated with the loss of white matter in the central nervous system (CNS). Several years after its first clinical description, ADLD was found to be caused by coding and non-coding variants in the LMNB1 gene that cause its overexpression in at least the brain of patients. LMNB1 encodes for Lamin B1, a protein of the nuclear lamina. Lamin B1 regulates many cellular processes such as DNA replication, chromatin organization, and senescence. However, its functions have not been fully characterized yet. Nevertheless, Lamin B1 together with the other lamins that constitute the nuclear lamina has firstly the key role of maintaining the nuclear structure. Being the nucleus a dynamic system subject to both biochemical and mechanical regulation, it is conceivable that changes to its structural homeostasis might translate into functional alterations. Under this light, this review aims at describing the pieces of evidence that to date have been obtained regarding the effects of LMNB1 overexpression on cellular morphology and functionality. Moreover, we suggest that further investigation on ADLD morpho-functional consequences is essential to better understand this complex disease and, possibly, other neurological disorders affecting CNS myelination
Pseudo-supersymmetry and a Tale of Alternate Realities
We discuss how all variant 10d and 11d maximal supergravities, including star
supergravities and supergravities in different signatures, can be obtained as
different real slices of three complex actions. As an application we study the
recently introduced domain-wall/cosmology correspondence in this approach. We
give an example in 9d and 10d where the domain-wall and corresponding cosmology
can be viewed as different real slices of the same complex solution. We argue
how in this case the pseudo-supersymmetry of the cosmological solutions can be
understood as the invariance under supersymmetry of a variant supergravity.Comment: 32 page
Supersymmetric solutions of gauged five-dimensional supergravity with general matter couplings
We perform the characterization program for the supersymmetric configurations
and solutions of the , Supergravity Theory coupled to an
arbitrary number of vectors, tensors and hypermultiplets and with general
non-Abelian gaugins. By using the conditions yielded by the characterization
program, new exact supersymmetric solutions are found in the
model for the hyperscalars and with as the gauge group. The
solutions also content non-trivial vector and massive tensor fields, the latter
being charged under the U(1) sector of the gauge group and with selfdual
spatial components. These solutions are black holes with
near horizon geometry in the gauged version of the theory and for the ungauged
case we found naked singularities. We also analyze supersymmetric solutions
with only the scalars of the vector/tensor multiplets and the metric
as the non-trivial fields. We find that only in the null class the scalars
can be non-constant and for the case of constant we refine
the classification in terms of the contributions to the scalar potential.Comment: Minor changes in wording and some typos corrected. Version to appear
in Class. Quantum Grav. 38 page
Analysis of LMNB1 Duplications in Autosomal Dominant Leukodystrophy Provides Insights into Duplication Mechanisms and Allele-Specific Expression
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