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P. A. Horvathy

Publications and source records attributed to P. A. Horvathy.

At least 91 records · Page 5Linked to original sources

Helicity supersymmetry of dyons

The 'dyon' system of D'Hoker and Vinet consisting of a spin 1/2 particle with anomalous gyromagnetic ratio 4 in the combined field of a Dirac monopole plus a Coulomb plus a suitable $1/r^2$ potential (which arises in the long-range limit of a self-dual monopole) is studied following Biedenharn's approach to the Dirac-Coulomb problem: the explicit solution is obtained using the `Biedenharn-Temple operator', $Γ$, and the extra two-fold degeneracy is explained by the subtle supersymmetry generated by the 'Dyon Helicity' or generalized `Biedenharn-Johnson-Lippmann' operator ${\cal R}$. The new SUSY anticommutes with the chiral SUSY discussed previously.

hep-th↗

The Dirac equation in Taub-NUT space

Using chiral supersymmetry, we show that the massless Dirac equation in the Taub-NUT gravitational instanton field is exactly soluble and explain the arisal and the use of the dynamical (super) symmetry.

hep-th↗

Berry phase correction to electron density in solids and "exotic" dynamics

Recent results on the semiclassical dynamics of an electron in a solid are explained using techniques developed for ``exotic'' Galilean dynamics. The system is indeed Hamiltonian and Liouville's theorem holds for the symplectic volume form. Suitably defined quantities satisfy hydrodynamic equations.

cond-mat.mes-hall↗

On Schrödinger superalgebras

We construct, using the supersymplectic framework of Berezin, Kostant and others, two types of supersymmetric extensions of the Schrödinger algebra (itself a conformal extension of the Galilei algebra). An `$I$-type' extension exists in any space dimension, and for any pair of integers $N_+$ and $N_-$. It yields an $N=N_++N_-$ superalgebra, which generalizes the N=1 supersymmetry Gauntlett et al. found for a free spin-$\half$ particle, as well as the N=2 supersymmetry of the fermionic oscillator found by Beckers et al. In two space dimensions, new, `exotic' or `$IJ$-type' extensions arise for each pair of integers $ν_+$ and $ν_-$, yielding an $N=2(ν_++ν_-)$ superalgebra of the type discovered recently by Leblanc et al. in non relativistic Chern-Simons theory. For the magnetic monopole the symmetry reduces to $ø(3)\times\osp(1/1)$, and for the magnetic vortex it reduces to $ø(2)\times\osp(1/2)$.

hep-th↗

Enlarged Galilean symmetry of anyons and the Hall effect

Enlarged planar Galilean symmetry, built of both space-time and field variables and also incorporating the ``exotic'' central extension is introduced. It is used to describe non-relativistic anyons coupled to an electromagnetic field. Our theory exhibits an anomalous velocity relation of the type used to explain the Anomalous Hall Effect. The Hall motions, characterized by a Casimir of the enlarged algebra, become mandatory for some critical value(s) of the magnetic field. The extension of our scheme yields the semiclassical effective model of the Bloch electron.

hep-th↗

Non-commuting coordinates, exotic particles, & anomalous anyons in the Hall effect

Our previous ``exotic'' particle, together with the more recent anomalous anyon model (which has arbitrary gyromagnetic factor $g$) are reviewed. The non-relativistic limit of the anyon generalizes the exotic particle which has $g=0$ to any $g$.When put into planar electric and magnetic fields, the Hall effect becomes mandatory for all $g\neq2$, when the field takes some critical value.

hep-th↗

Symmetries of field theories on the non-commutative plane

New developments on the symmetries of non-relativistic field theoretical models on the non commutative plane are reviewed. It is shown in particular that Galilean invariance strongly restricts the admissible interactions. Moreover, if a scalar field is coupled to a Chern - Simons gauge field, a geometrical phase emerges for vortex - like solutions, transformed by Galilei boosts.

hep-th↗

Edge solitons in the QHE

The spacelike reduction of the Chern-Simons Lagrangian yields a modified Nonlinear Schrödinger Equation (jNLS) where in the non-linearity the particle density is replaced by current. When the phase is linear in the position, this latter is an ordinary NLS with time-dependent coefficients which admits interesting solutions. Their arisal is explained by the conformal properties of non-relativistic spacetime. Only the usual travelling soliton is consistent with the jNLS, but the addition of a six-order potential converts it into an integrable equation.

hep-th↗

New applications of the Biedenharn-Temple operator

The Biedenharn approach to the Dirac-Coulomb problem is applied to a system considered by D'Hoker and Vinet, which consists of a spin $\2$ particle in the combined field of a Dirac monopole plus a $λ^2/r^2$ potential. The explicit solution is obtained by diagonalizing the Biedenharn-Temple operator, $Γ$.

hep-th↗

Anyons with anomalous gyromagnetic ratio & the Hall effect

Letting the mass depend on the spin-field coupling as $M^2=m^2-(eg/2c^2)F_{αβ}S^{αβ}$, we propose a new set of relativistic planar equations of motion for spinning anyons. Our model can accommodate any gyromagnetic ratio $g$ and provides us with a novel version of the Bargmann-Michel-Telegdi equations in 2+1 dimensions. The system becomes singular when the field takes a critical value, and, for $g\neq2$, the only allowed motions are those which satisfy the Hall law. For each $g\neq2,0$ a secondary Hall effect arises also for another critical value of the field. The non-relativistic limit of our equations yields new models which generalize our previous ``exotic'' model, associated with the two-fold central extension of the planar Galilei group.

hep-th↗

Moving vortices in noncommutative gauge theory

Exact time-dependent solutions of nonrelativistic noncommutative Chern - Simons gauge theory are presented in closed analytic form. They are different from (indeed orthogonal to) those discussed recently by Hadasz, Lindstrom, Rocek and von Unge. Unlike theirs, our solutions can move with an arbitrary constant velocity, and can be obtained from the previously known static solutions by the recently found ``exotic'' boost symmetry.

hep-th↗

Noncommuting coordinates in the Hall effect and in vortex dynamics

Laughlin's Ansatz to explain the fractional Quantum Hall effect is derived by coupling a particle associated with ``exotic'' the two-fold central extension of the planar Galilei group. The reduced system is identical to the one used to describe the dynamics of vortices in an incompressible planar fluid.

hep-th↗

Chern-Simons vortices

In (2+1) dimensions, the Maxwell term $-(1/4) F_{αβ}F^{αβ}$ can be replaced by the Chern-Simons three-form $(κ/4)ε^{αβγ}A_αF_{βγ}$, yielding a novel type of `electromagnetism'. This has been proposed for studying the Quantum Hall Effect as well as High-Temperature Superconductivity. The gauge field can be coupled to a scalar field either relativistically or non-relativistically. In both cases, one admits finite-energy, vortex solutions.

hep-th↗

Galilean noncommutative gauge theory: symmetries & vortices

Noncommutative Chern-Simons gauge theory coupled to nonrelativistic scalars or spinors is shown to admit the ``exotic'' two-parameter-centrally extended Galilean symmetry, realized in a unique way consistent with the Seiberg-Witten map. Nontopological spinor vortices and topological external-field vortices are constructed by reducing the problem to previously solved self-dual equations.

hep-th↗

Vanishing of the conformal anomaly for strings in a gravitational wave

Using the non-symmetric-connection approach proposed by Osborn, we demonstrate that, for a bosonic string in a specially chosen plane-fronted gravitational wave and an axion background, the conformal anomaly vanishes at the two-loop level. Under some conditions, the anomaly vanishes at all orders.

hep-th↗