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Emilio Torrente-Lujan

Publications and source records attributed to Emilio Torrente-Lujan.

17 recordsLinked to original sources

Hawking--Page Universality, Thermodynamic Dipoles and Categorical Defects

We reconsider the Hawking--Page transition using the common thermodynamic vector field whose zeros include the Davies and Hawking--Page points. In the elementary AdS branch their winding numbers are $w_{\rm D}=-1$ and $w_{\rm HP}=+1$, so the pair has zero total charge but a non-zero signed first moment. After normalization by the Davies scales this moment gives the familiar universal ratios $C_S$ and $C_T$; in four dimensions $C_S=2$ and $C_T=2/\sqrt{3}-1$. We check the construction for Schwarzschild--AdS, grand-canonical Reissner--Nordström--AdS, charged non-rotating black holes in arbitrary dimension, and Kerr--AdS at fixed angular velocity. The same reduced geometry gives a barrier $B=1/3$ in four dimensions and $B(d)=1/[(d-1)(d-3)]$. Finally we propose a formulation involving a defect-resolved version for categorical or non-invertible symmetry sectors.

hep-th

Dissipative non-Abelian fluids from Scherk-Schwarz dimensional reduction

We construct a $d$-dimensional dissipative colored fluid by Scherk--Schwarz reduction of a neutral viscous conformal fluid in $D=d+n$ dimensions on an $n$-dimensional unimodular group manifold. The off-diagonal components of the higher-dimensional stress tensor become non-Abelian color currents, while the higher-dimensional shear tensor induces shear, bulk-like and vector-dissipative structures in the reduced theory. We derive the map for the equation of state, sound speed, color current, entropy current and first-order transport coefficients. In particular, \[ η=\ee^{αφ}\coshξ\,\heta,\qquad τ=η\,\frac{n}{(D-1)(d-1)},\qquad κ=η\sinh^2ξ. \] We also spell out the hydrodynamic-frame issue induced by dimensional reduction, discuss the status of the internal rapidity field $ξ$, and give a detailed account of how the second law descends from the parent theory, including the roles of temperature-dependent viscosity, non-unimodular groups and possible choices for $ξ$. The construction should be regarded as a toy model for non-Abelian dissipative hydrodynamics with the potential of paving the way to direct phenomenological model of, for example, quark--gluon plasma.

hep-th

Star-Shaped Integral Cartan-Type Matrices and an Egyptian-Fraction Classification of Affine Weighted Trees

We study a concrete family of symmetric integral $Z$-matrices attached to weighted star trees. The arms are ordinary type-$A$ chains and the central diagonal entry is an arbitrary positive integer $k$ rather than being fixed to the Cartan value $2$. This gives a matrix-theoretic and graph-theoretic version of the so called Berger construction: it extends the simply laced affine Dynkin stars while remaining accessible through elementary linear algebra. For a star with arm lengths $r_1,\ldots,r_m$ we compute the determinant, the inertia, the positive-definite and affine regimes, and the primitive positive null vector in the affine case. The affine condition is exactly the unit-fraction equation \[ \sum_{i=1}^m \frac{1}{r_i+1}=m-k, \] so the classification of these affine weighted trees reduces to a finite Egyptian-fraction enumeration for each fixed pair $(m,k)$. The classical affine diagrams $D_4^{(1)}$, $E_6^{(1)}$, $E_7^{(1)}$ and $E_8^{(1)}$ appear as small subfamilies, while higher-arm cases give new integral positive-semidefinite star matrices with explicit Coxeter labels.

math.CO

On Universal Constants of AdS Black Holes from Hawking-Page Phase Transition

We investigate the thermodynamic properties of the Hawking-Page phase transition of AdS black holes. We present evidence for the existence of two universal critical constants associated with the Hawking-Page (HP) and minimum black hole thermodynamical transition points. These constants are defined by C_S =\frac{S_{HP}-S_{min}}{S_{min}} and C_T =\frac{T_{HP}-T_{min}}{T_{min}} where S_{min}(S_{HP}) and T_{min}(T_{HP}) are the minimal (HP phase transition) entropy and temperature, respectively, below which no black hole can exist. For a large class of four dimensional non-rotating black holes, we find C_S =2 and C_T = \frac{2-\sqrt{3}}{\sqrt{3}}. For the rotating case, however, such universal ratios are slightly affected without losing the expected values. Taking small values of the involved rotating parameter, we recover the same constants. Higher dimensional models, with other universal constants, are also discussed in some details.

hep-th

Entanglement Renormalization for Interacting Field Theories

A general method to build the entanglement renormalization (cMERA) for interacting quantum field theories is presented. We improve upon the well-known Gaussian formalism used in free theories through a class of variational non-Gaussian wavefunctionals for which expectation values of local operators can be efficiently calculated analytically and in a closed form. The method consists of a series of scale-dependent nonlinear canonical transformations on the fields of the theory under consideration. Here, the $λ\, ϕ^4$ and the sine-Gordon scalar theories are used to illustrate how non-perturbative effects far beyond the Gaussian approximation are obtained by considering the energy functional and the correlation functions of the theory.

hep-th

Toward minimal renormalizable SUSY SU(5) Grand Unified Model with tribimaximal mixing from A4 Flavor symmetry

We address the problem of rationalizing the pattern of fermion masses and mixings by adding a nonabelian flavor symmetry in a grand unified framework. With this purpose, we include an A4 flavor symmetry into a unified renormalizable SUSY GUT SU(5) model. With the help of the "Type II Seesaw" mechanism we are able to obtain the pattern of observed neutrino mixings in a natural way, through the so called tribimaximal matrix.

hep-ph

Neutrino masses and tribimaximal mixing in the minimal renormalizable supersymmetric SU(5) grand unified model with A4 flavor symmetry

We analyze all possible extensions of the recently proposed minimal renormalizable SUSY SU(5) grand unified model with the inclusion of an additional A4 flavor symmetry. We find that there are five possible cases but only one of them is phenomenologically interesting. We develop in detail such case and we show how the fermion masses and mixing angles come out. As a prediction we obtain the neutrino masses of order of 0.1 eV with an inverted hierarchy.

hep-ph

Predictions from non trivial Quark-Lepton complementarity

The complementarity between the quark and lepton mixing matrices is shown to provide robust predictions. We obtain these predictions by first showing that the matrix V_M, product of the quark (CKM) and lepton (PMNS) mixing matrices, may have a zero (1,3) entry which is favored by experimental data. We obtain that any theoretical model with a vanishing (1,3) entry of V_M that is in agreement with quark data, solar, and atmospheric mixing angle leads to $θ_{13}^{PMNS}=(9{^{+1}_{-2}})^\circ$. This value is consistent with the present 90% CL experimental upper limit. We also investigate the prediction on the lepton phases. We show that the actual evidence, under the only assumption that the correlation matrix V_M product of CKM and PMNS has a zero in the entry (1,3), gives us a prediction for the three CP-violating invariants J, S_1, and S_2. A better determination of the lepton mixing angles will give stronger prediction for the CP-violating invariants in the lepton sector. These will be tested in the next generation experiments. Finally we compute the effect of non diagonal neutrino mass in "l_i -> l_j gamma" in SUSY theories with non trivial Quark-Lepton complementarity and a flavor symmetry. The Quark-Lepton complementarity and the flavor symmetry strongly constrain the theory and we obtain a clear prediction for the contribution to "mu -> e gamma" and the "tau" decays "tau -> e gamma" and "tau -> mu gamma". If the Dirac neutrino Yukawa couplings are degenerate but the low energy neutrino masses are not degenerate, then the lepton decays are related among them by the V_M entries. On the other hand, if the Dirac neutrino Yukawa couplings are hierarchical or the low energy neutrino masses are degenerate, then the prediction for the lepton decays comes from the CKM hierarchy.

hep-ph

A model for fermion masses and lepton mixing in SO(10) x A4

The discrete flavor symmetry A4 explains very well neutrino data at low energy, but it seems difficult to extend it to grand unified models since in general left-handed and right-handed fields belong to different A4 representations. Recently it has been proposed a model where all the fermions equally transform under A4. We study here a concrete SO(10) realization of such a model providing small neutrino masses through the seesaw mechanism. We fit at tree level the charged fermion masses run up to the unification scale. Some fermion masses properties come from the SO(10) symmetry while lepton mixing angles are consequence of the A4 properties. Moreover, our model predicts the absolute value of the neutrino masses, these ones are in the range $m_ν\simeq 0.005-0.052 eV$.

hep-ph

Quark-lepton complementarity, neutrino and standard model data predict $(θ_{13}^{PMNS}=9^{+1}_{-2})^\circ$

The complementarity between the quark and lepton mixing matrices is shown to provide a robust prediction for the neutrino mixing angle $θ_{13}^{PMNS}$. We obtain this prediction by first showing that the matrix $V_M$, product of the CKM and PMNS mixing matrices, may have a zero (1,3) entry which is favored by experimental data. Hence models with bimaximal or tribimaximal forms of the correlation matrix $V_M$ are quite possible. Any theoretical model with a vanishing (1,3) entry of $V_M$ that is in agreement with quark data, solar, and atmospheric mixing angle leads to $θ_{13}^{PMNS}=(9{^{+1}_{-2}})^\circ$. This value is consistent with the present 90% CL experimental upper limit.

hep-ph

Hamevol1.0: a C++ code for differential equations based on Runge-Kutta algorithm. An application to matter enhanced neutrino oscillation

We present a C++ implementation of a fifth order semi-implicit Runge-Kutta algorithm for solving Ordinary Differential Equations. This algorithm can be used for studying many different problems and in particular it can be applied for computing the evolution of any system whose Hamiltonian is known. We consider in particular the problem of calculating the neutrino oscillation probabilities in presence of matter interactions. The time performance and the accuracy of this implementation is competitive with respect to the other analytical and numerical techniques used in literature. The algorithm design and the salient features of the code are presented and discussed and some explicit examples of code application are given.

cs.CE

Baryon asymmetry at the weak phase transition in presence of arbitrary CP violation

We consider interactions of fermions with the domain wall bubbles produced during a first order phase transition. A new exact solution of the Dirac equations is obtained for a wall profile incorporating a position dependent CP violating phase. The reflection coefficients are computed, a resonance effect is uncovered for rapidly varying phases. This resonance effect happens when the energy and mass of the incident particles are $E/m=Δθ/2$. Where $Δθ$ is the phase variation across the wall width. We calculate the chiral charge flux through the wall surface and the corresponding baryon asymmetry of the Universe. It agrees in sign and magnitude with the observed baryonic excess $ρ_B/s\approx 10^{-10}$ for a large range of parameters and CP violation. As a function of $Δθ$, the ratio $ρ_b/s$ reach a maximum for $Δθ\approx 2-4π$ and $m\approx m_{top}$. PACS: 11.27.+d, 03.65.-w, 02.30.Hq, 02.30.Gp, 11.30.Fs, 98.80.Cq

hep-ph

Fermion Scattering in domain walls with a locally dependent phase

We consider interactions of fermions with the domain wall bubbles produced during a first order phase transition. A new exact solution of the Dirac equations is obtained for a wall profile incorporating a position dependent phase factor. The reflection coefficients are obtained.

hep-ph

A Quasi-maximal mixing ansatz for neutrino oscillations

Inspired by the atmospheric multi-GeV neutrino data, we consider neutrino flavor mixing matrices which are maximal in a $2\times 2$ subsector. This condition is a strong restriction: the full matrix including complex phases depends essentially on one parameter. The survival probability is an universal function of $L/E$, independent of generation, in the region of interest for the accelerator and atmospheric experiments. It is possible with the solar neutrino data alone to recover completely the mixing matrix suggested by the atmospheric data. The results are not essentially modified by the MSW effect in the solar data. Consequences for future experiments are considered.

hep-ph

An exact analytic description of neutrino oscillations in matter with exponentially varying density for arbitrary number of neutrino species

Exact analytical expressions in terms of generalized confluent hypergeometric functions for the transition amplitudes of neutrino oscillations in presence of matter are computed for an arbitrary number of species. The density of matter is assumed to be exponentially decaying. The results can be used for the description of matter-induced neutrino oscillations in the Sun which can take place when the solar neutrinos propagate radially from the interior to the surface. Expressions are particularly simple in the limit of infinite propagation time as is suitable for the case of detection at Earth. PACS: 14.60.Pq, 02.30.Gp, 02.30.Hq

hep-ph

Neutrino Oscillations and the MSW effect in Random Solar Matter

We investigate the effects of random density fluctuations on neutrino oscillations in the Sun environment. We show how the average of certain quantities which can be used to describe the MSW effect can be computed analytically. We examine also the hypothesis commonly accepted that only perturbations inside the resonance layer can have relevance. The average amplitud, which gives the ''coherent probability'', is computed in an analytical and exact way for the case of colored $δ$-correlated gaussian noise: the random perturbation induces a renormalization of the matter density which adquires an imaginary part proportional to the fluctuation amplitud at the resonance region. Integral equations are given for the density matrix of the system in the ''optical'' approximation. PACS: 96.60.Kx, 02.50.Ey, 14.60.Pq,95.30.Cq, 96.60.Hv,14.60.Gh.

hep-ph