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J. Mateos Guilarte

Publications and source records attributed to J. Mateos Guilarte.

At least 19 recordsLinked to original sources

The Jackiw-Rebbi model. Bose/Fermi one-loop Kink mass shifts

Scalar and spinor Kink fluctuations are summarized in the Jackiw-Rebbi model. Canonical quantization is conventionally achieved by promoting the coefficients of the scalar and spinor field expansions to bosonic/fermionic creation/annihilation operators. One-particle states for bosons, respectively for fermions, are supplied by the scalar eigenfunctions of the Schr$\ddot{\rm o}$dinger, respectively, the eigenspinors of the Dirac Hamiltonian, evaluated either on the ground state or the Kink background. One-loop kink mass shifts are computed induced either by bosons or fermions. Both bound and scattering states contribute when the quanta are trapped by or scattered off the Kink. Zero modes of Kink fluctuations bosonic and fermionic do not modify the Kink mass at one-loop order. The Dashed-Hasslacher-Neveu prescription, derived in the canonical quantization framework, is generalized to the fermionic realm. Alternatively, quantization à la Feynman of the Jackiw-Rebbi model in the spaces of Kink scalar and spinor fluctuations is developed. It is ensured that Berezin integration over the Grassmann coefficients of the Kink spinor fluctuations leads to identical scenario as that revealed by including Fermi statistics in the DHN paradigm, at least with respect to the computation of the Kink Casimir energy.

hep-th↗

Low energy dynamics of vibrating Kinks

Low energy dynamics of Kinks and Kink-AntiKink configurations in the Jackiw-Rebbi model is fully described. The strategy is based in the Collective Coordinates adiabatic approach. The necessary solution of Quantum Mechanical spectral problems, both for scalar and spinorial wave functions, is unveiled as an intermediate step.

hep-th↗

Dynamics of Excited BPS 3-Vortices

We analyze the dynamics of BPS 3-vortex solutions. First, for unexcited vortices, we study the 2-dimensional moduli space of centred vortices with $y \to -y$ symmetry, and its metric. We identify the 1-dimensional subspaces describing the head-on collisions of equidistant collinear and equilateral triangle configurations, where geodesic motion results in $90^\circ$ and 60^\circ$ scattering, respectively. Second, by studying the frequency spectrum of vibrational shape modes along these subspaces, we explain how the force-free, geodesic motion is modified by shape mode excitations into a pattern of chaotic multi-bounce collisions.

hep-th↗

Collective Coordinate Models for 2-Vortex Shape Mode Dynamics

Models are developed for the motion of charge-2 Abelian Higgs vortices through the 2-vortex moduli space $M$, with the vortices excited by their shape mode oscillations. The models simplify to the well-known geodesic flow on $M$, modified by a potential, when the mode oscillations are fast relative to the moduli space motion and their amplitudes are small. When the lowest-frequency mode is excited with a large amplitude, the geodesic flow is not a correct description. Instead, a chaotic, or even fractal, multi-bounce structure in vortex-vortex collisions is predicted.

hep-th↗

Spectral Flow of Vortex Shape Modes over the BPS 2-Vortex Moduli Space

The flow of shape eigenmodes of the small fluctuation operator around BPS 2-vortex solutions is calculated, as a function of the intervortex separation $2d$. For the rotationally-invariant 2-vortex, with $d = 0$, there are three discrete modes; the lowest is non-degenerate and the upper two are degenerate. As $d$ increases, the degeneracy splits, with one eigenvalue increasing and entering the continuous spectrum, and the other decreasing and asymptotically coalescing with the lowest eigenvalue, where they jointly become the eigenvalue of the 1-vortex radial shape mode. The behaviour of the eigenvalues near $d=0$ is clarified using a perturbative analysis, and also in light of the 2-vortex moduli space geometry.

hep-th↗

A Note on a Generalized AHM Model with Analytical Vortex Solutions

We study topological vortex solutions in a generalized Abelian Higgs model with non-polynomial dielectric and potential functions. These quantities are chosen by requiring integrability of the self-dual limit of the theory for all values of the magnetic flux. All the vortex profiles are described by exact analytical expressions that solve the self-dual vortex equations. There is only a symmetry-breaking superconducting phase and the model sustains regular phenomenology.

hep-th↗

Kinks in massive non-linear ${\mathbb S}^1\times{\mathbb S}^1$-Sigma models

In this paper the whole kink varieties arising in several massive non-linear Sigma models whose target space is the torus ${\mathbb S}^1\times{\mathbb S}^1$ are analytically calculated. This possibility underlies the construction of first-order differential equations by adapting the Bogomolny procedure to non-Euclidean spaces. Among the families of solutions non-topological kinks connecting the same vacuum are found. This class of solutions are usually considered to be not globally stable. However, in this context the topological constraints obtained by the non-simply connectedness of the target space turn these non-topological kinks into globally stable solutions. The analytical resolution of the equations allows the complete study of the linear stability for some basic kinks.

nlin.PS↗

Two species of semi-local cosmic strings in Abelian gauged $\mathbb{CP}^2$-sigma models coupled to gravity

We study a semi-local Abelian Higgs sigma model with $\mathbb{CP}^2$-valued scalar fields coupled to gravity. We establish the conditions needed for self-duality in this system and obtain cosmic strings, both of self-dual character and out of the self-dual point, in the reference chart of $\mathbb{CP}^2$. In any of the other two charts of a minimum atlas, the transition functions break the global $SU(2)$ symmetry to the Abelian subgroup $e^{i σ^3 α}$. In this context, using the transition functions a new self-dual structure can be constructed, which defines a second species of cosmic strings. Because of the presence of a potential energy for the scalar fields, each species takes values in a different bounded region of the target space and is most naturally described using a particular chart of $\mathbb{CP}^2$.

hep-th↗

One-dimensional scattering of fermions on $δ$-impurities

We study the spectrum of the 1D Dirac Hamiltonian encompassing the bound and scattering states of a fermion distorted by a static background built from $δ$-function potentials. We distinguish between "mass-spike" and "electrostatic" $δ$-potentials. Differences in the spectra arising depending on the type of $δ$-potential studied are thoroughly explored.

math-ph↗

On self-gravitating kinks in two-dimensional pseudo-riemannian universes

Two-dimensional scalar field theories with spontaneous symmetry breaking subject to the action of Jackiw-Teitelboim gravity are studied. Solutions for the $ϕ^4$ and sine-Gordon self-gravitating kinks are presented, both for general gravitational coupling and in the perturbative regime. The analysis is extended to deal with a hierarchy of kinks related to transparent Pöschl-Teller potentials

hep-th↗

Fractional Fermion Number and Hall Conductivity of Domain Walls

In this letter the fractional fermion number of thick domain walls is computed. The analysis is achieved by developing the heat kernel expansion of the spectral eta functon of the Dirac Hamiltonian governing the fermionic fluctuations around the domain wall. A formula is derived showing that a non null fermion number is always accompanied by a Hall conductivity induced on the wall. In the limit of thin and impenetrable walls the chiral bag boundary conditions arise, and the Hall conductivity is computed for this case as well.

hep-th↗

Electron-positron planar orbits in a constant magnetic field

The different types of orbits in the classical problem of two particles with equal masses and opposite charges on a plane under the influence of a constant orthogonal magnetic field are classified. The equations of the system are reduced to the problem of a Coulomb center plus a harmonic oscillator. The associated bifurcation diagram is fully explained. Using this information the dynamics of the two particles is described.

math-ph↗

Soliton Fermionic number from the heat kernel expansion

We consider different methods of calculating the (fractional) fermion number of solitons based on the heat kernel expansion. We derive a formula for the localized eta function a more systematic version of the derivative expansion for spectral assymmetry and that provides a more systematic version of the derivative expansion for spectral asymmetry and compute the fermion number in a multiflavour extension of the Goldstone-Wilczek model.We also propose an improved expansionof the heat kernelthat allows the tackling ofthe convergence issues and permits an automated computation of the coefficients

hep-th↗

Equivalence between Type I Liouville dynamical systems in the plane and the sphere

Separable Hamiltonian systems either in sphero-conical coordinates on a $S^2$ sphere or in elliptic coordinates on a ${\mathbb R}^2$ plane are described in an unified way. A back and forth route connecting these Liouville Type I separable systems is unveiled. It is shown how the gnomonic projection and its inverse map allow us to pass from a Liouville Type I separable system with an spherical configuration space to its Liouville Type I partner where the configuration space is a plane and back. Several selected spherical separable systems and their planar cousins are discussed in a classical context.

math-ph↗

Orbits in the problem of two fixed centers on the sphere

A trajectory isomorphism between the two Newtonian fixed center problem in the sphere and two associated planar two fixed center problems is constructed by performing two simultaneous gnomonic projections in $S^2$. This isomorphism converts the original quadratures into elliptic integrals and allows the bifurcation diagram of the spherical problem to be analyzed in terms of the corresponding ones of the planar systems. The dynamics along the orbits in the different regimes for the problem in $S^2$ is expressed in terms of Jacobi elliptic functions.

math-ph↗

Elementary solutions of the quantum planar two center problem

The quantum problem of an electron moving in a plane under the field created by two Coulombian centers admits simple analytical solutions for some particular inter-center distances. These elementary eigenfunctions, akin to those found by Demkov for the analogous three dimensional problem, are calculated using the framework of quasi-exact solvability of a pair of entangled ODE's descendants from the Heun equation. A different but interesting situation arises when the two centers have the same strength. In this case completely elementary solutions do not exist.

math-ph↗

Quantum magnetic flux lines, BPS vortex zero modes, and one-loop string tension shifts

Spectral heat kernel/zeta function regularization procedures are employed in this paper to control the divergences arising from vacuum fluctuations of Bogomolnyi-Prasad-Sommerfield vortices in the Abelian Higgs model. Zero modes of vortex fluctuations are the source of difficulties appearing when the standard Gilkey-de Witt expansion is performed. A modified GdW expansion is developed to diminish the impact of the infrared divergences due to the vortex zero modes. With this new technique at our disposal we compute the one-loop vortex mass shift in the planar AHM and the quantum corrections to the string tension of the magnetic flux tubes living in three dimensions. In both cases it is observed that weak repulsive forces surge between these classically non interacting topological defects caused by vacuum quantum fluctuations.

hep-th↗

A note on BPS vortex bound states

In this note we investigate bound states, where scalar and vector bosons are trapped by BPS vortices in the Abelian Higgs model with a critical ratio of the couplings. A class of internal modes of fluctuation around cylindrically symmetric BPS vortices is characterized mathematically, analysing the spectrum of the second-order fluctuation operator when the Higgs and vector boson masses are equal. A few of these bound states with low values of quantized magnetic flux are described fully, and their main properties are discussed.

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