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J. W. van Holten

Publications and source records attributed to J. W. van Holten.

68 records · Page 4Linked to original sources
arXiv1995

D = 1 Supergravity and Spinning Particles

In this paper I review the multiplet calculus of $N = 1$, $D = 1$ local supersymmetry with applications to the construction of models for spinning particles in background fields, and models with space-time supersymmetry. New features include a non-linear realization of the local supersymmetry algebra and the coupling to anti-symmetric tensor fields of both odd and even rank. The non-linear realization allows the construction of a $D = 1$ cosmological-constant term, which provides a mass term in the equations of motion.

hep-th↗
arXiv1995

Killing tensors and a new geometric duality

We present a theorem describing a dual relation between the local geometry of a space admitting a symmetric second-rank Killing tensor, and the local geometry of a space with a metric specified by this Killing tensor. The relation can be generalized to spinning spaces, but only at the expense of introducing torsion. This introduces new supersymmetries in their geometry. Interesting examples in four dimensions include the Kerr-Newman metric of spinning black-holes and self-dual Taub-NUT.

hep-th↗
arXiv1995

Propagators and Path Integrals

Path-integral expressions for one-particle propagators in scalar and fermionic field theories are derived, for arbitrary mass. This establishes a direct connection between field theory and specific classical point-particle models. The role of world-line reparametrization invariance of the classical action and the implementation of the corresponding BRST-symmetry in the quantum theory are discussed. The presence of classical world-line supersymmetry is shown to lead to an unwanted doubling of states for massive spin-1/2 particles. The origin of this phenomenon is traced to a `hidden' topological fermionic excitation. A different formulation of the pseudo-classical mechanics using a bosonic representation of $\gam_5$ is shown to remove these extra states at the expense of losing manifest supersymmetry.

hep-th↗
arXiv1995

New Supersymmetry of the Monopole

The non-relativistic dynamics of a spin-1/2 particle in a monopole field possesses a rich supersymmetry structure. One supersymmetry, uncovered by d'Hoker and Vinet, is of the standard type: it squares to the Hamiltonian. In this paper we show the presence of another supersymmetry which squares to the Casimir invariant of the full rotation group. The geometrical origin of this supersymmetry is traced, and its relationship with the constrained dynamics of a spinning particle on a sphere centered at the monopole is described.

hep-th↗
arXiv1995

Domain boundaries, Goldstone bosons and gravitational waves

The dynamical behaviour of domain boundaries between different realizations of the vacuum of scalar fields with spontaneously broken phases is investigated. They correspond to zero-modes of the Goldstone fields, moving with the speed of light, and turn out to be accompanied by strongly oscillating gravitational fields. In certain space-time topologies this leads to a quantization condition for the symmetry breaking scale in terms of the Planck mass.

hep-th↗
arXiv1994

Killing-Yano tensors and generalized supersymmetries in black-hole and monopole geometries

New kinds of supersymmetry arise in supersymmetric $\sg$-models describing the motion of spinning point-particles in classical backgrounds, for example black-holes, or the dynamics of monopoles. Their geometric origin is the existence of Killing-Yano tensors. The relation between these concepts is explained and examples are given. --- Contribution to Proceedings Quarks-94; Vladimir, Russia (1994).

hep-th↗
arXiv1994

Supersymmetry and the Geometry of Taub-NUT

The supersymmetric extension of Taub-NUT space admits 4 standard supersymmetries plus several additional non-standard ones. The geometrical origin of these symmetries is traced. The result has applications to fermion modes in gravitational instantons as well as in long-range monopole dynamics.

hep-th↗
arXiv1994

Extended Geometry of Black Holes

We reconsider space-time singularities in classical Einsteinian general relativity: with the help of several new co-ordinate systems we show that the Schwarzschild solution can be extended beyond the curvature singularity at r=0. The extension appears as an infinite covering of standard Kruskal space-time. While the two-dimensional reduction of this infinite sequence of Kruskal-Szekeres domains obtained by suppressing the angular degrees of freedom is still a topological manifold - albeit one for which the metric structure is singular on one-dimensional submanifolds - we obtain for the full four-dimensional geometry the more general structure of a stratified variety.

gr-qc↗
arXiv1993

New supersymetries for spinning particles and black holes

The usual extensions of supersymmetry require the existence of a complex structure and the formulation of the theory on Kähler manifolds. It is shown, that by relaxing the constraints on the algebra of supercharges we can get new supersymmetries whenever a manifold possesses a structure admitting the existence of a Killing-Yano tensor field. Examples of such manifolds are the Kerr-Newman space-times describing spinning black holes in four dimensions.

hep-th↗
arXiv1993

Relativistic Dynamics of Spin in Strong External Fields

The dynamics of relativistic spinning particles in strong external electromagnetic or gravitational fields is discussed. Spin-orbit coupling is shown to affect such relativistic phenomena as time-dilation and perihelion shift. Possible applications include muon decay in a magnetic field and the dynamics of neutron stars in binary systems.

hep-th↗
arXiv1993

SUSY in the sky

Spinning particles in curved space-time can have fermionic symmetries generated by the square root of bosonic constants of motion other than the Hamiltonian. We present a general analysis of the conditions under which such new supersymmetries appear, and discuss the Poisson-Dirac algebra of the resulting set of charges, including the conditions of closure of the new algebra. An example of a new non-trivial supersymmetry is found in black-hole solutions of the Kerr-Newman type and corresponds to the Killing-Yano tensor, which plays an important role in solving the Dirac equation in these black-hole metrics.

hep-th↗
arXiv1992

Symmetries and Motions in Manifolds

In these lectures the relations between symmetries, Lie algebras, Killing vectors and Noether's theorem are reviewed. A generalisation of the basic ideas to include velocity-dependend co-ordinate transformations naturally leads to the concept of Killing tensors. Via their Poisson brackets these tensors generate an {\em a priori} infinite-dimensional Lie algebra. The nature of such infinite algebras is clarified using the example of flat space-time. Next the formalism is extended to spinning space, which in addition to the standard real co-ordinates is parametrized also by Grassmann-valued vector variables. The equations for extremal trajectories (`geodesics') of these spaces describe the pseudo-classical mechanics of a Dirac fermion. We apply the formalism to solve for the motion of a pseudo-classical electron in Schwarzschild space-time.

hep-th↗
arXiv1992

BRST Field Theory of Relativistic Particles

A generalization of BRST field theory is presented, based on wave operators for the fields constructed out of, but different from the BRST operator. We discuss their quantization, gauge fixing and the derivation of propagators. We show, that the generalized theories are relevant to relativistic particle theories in the Brink-Di Vecchia-Howe-Polyakov (BDHP) formulation, and argue that the same phenomenon holds in string theories. In particular it is shown, that the naive BRST formulation of the BDHP theory leads to trivial quantum field theories with vanishing correlation functions.

hep-th↗