Dynamical Supersymmetry Research Articles

Dynamical supersymmetry breaking due to vacuum tunneling.

Dynamical supersymmetry breaking due to vacuum tunneling.

Fermion number exchange processes and dynamical supersymmetry effects in the interaction of fermionic zero modes with matter

The influence of fermionic zero modes and fractional charges caused by a topological soliton on the dynamics of the system is considered.

Effective potential in N=1 supergravity de sitter space

The one-loop effective action for the gravitino scalar condensate σ= ϵ μϵ μ in N=1 supergravity in de Sitter space is obtained. The action turns out to be real for some σ. This indicates the possibility of dynamical supersymmetry breaking. The effective potential for the fields σ in N=1 supergravity in flat space is calculated. This potential always contains an imaginary part.

Strings and D=4

It is argued that the unique infrared behaviour of non-abelian gauge couplings in four dimensions could be responsible, in closed super- (or heterotic) string theory, for dynamical supersymmetry breaking and for compactification to D=4 with string-scale compactified radii.

Superrenormalizability in a model with supersymmetry breaking.

A well-known model, due to Zanon, which exhibits dynamical supersymmetry breaking at large N is reexamined. The breaking is known to be pathological because the Goldstone fermion has negative norm. Here the two-loop corrections to the large-N effective potential are computed, and it is seen that the effect of the negative-norm state is to soften ultraviolet divergences beyond what is found in perturbation theory, rendering the model superrenormalizable in the loop expansion.

Dynamical and kinematical supersymmetries of the quantum harmonic oscillator and the motion in a constant magnetic field

Dynamical and kinematical symmetries and supersymmetries of the n-dimensional harmonic oscillator are discussed in connection with two different supersymmetrisation procedures: the so-called standard and spin-orbit coupling procedures. The largest invariance structures appear within the standard procedure dealing with the same numbers of bosonic and fermionic degrees of freedom. The authors also obtain meaningful substructures within the spin-orbit coupling procedure dealing with fermionic degrees of freedom which are half of the bosonic ones. Finally the n=2 case is connected with the study of the motion in a constant magnetic field. Each procedure leads to a nice correspondence between the two systems under consideration.

Dynamical superalgebra and supersymmetry for a many-fermion system.

A linearization scheme is proposed for the general Hamiltonian of an interacting fermion system, consisting of a mean-field approximation in which pairing and umklapp play dominant roles. A variety of models emerge, characterized by a hierarchy of spectrum-generating algebras and superalgebras, of which some are supersymmetric. The superconducting phase transition is shown to be related to supersymmetry breaking.

SUSY QCD effective action in the large Nc limit

A low energy effective action for supersymmetric quantum chromodynamics (SUSY QCD) including anomalous terms is constructed in the leading order of the 1 N expansion. The absence of dynamical supersymmetry breaking is explicitly demonstrated.

Odd-odd nucleus198Au as first test of IBFFM (OTQM)

The levels of198Au have been calculated in IBFFM as a first application of the new model for odd-odd nuclei. The study of the Au (n, γ) spectrum has led to a large amount of data on the odd-odd nucleus198Au, with spin/parity assignments of numerous low-lying states /l/. In particular, fifteen 1−, 2− levels have been found below 500 keV. However, at that time a detailed comparison with nuclear structure theory was not possible. In last decade, the interacting boson model was extensively applied to description of even-even and odd-even nuclei /2,3/. Only recently, this approach was extended to odd-odd nuclei /4–8/. A new model /4,5/ for odd-odd nuclei was introduced, referred to as IBFFM or OTQM. In related development, a few dynamical symmetries and supersymmetries have been introduced, which encompass odd-odd nuclei. These supersymmetries are associated with Uν (6/4)×Uπ (6/4) /6/, Uν(6/12)×Uπ (6/4) /7/ and with a symplectic chain /8/.

Dynamical supersymmetries of the harmonic oscillator

The largest spectrum generating superalgebra of the one-dimensional harmonic oscillator is determined as a semidirect sum Osp( 2 2 ) □ Sh(1) where Sh(1) is called the Heisenberg supersubalgebra. Its representation within an energy basis is given.

Possible evidence for dynamical supersymmetry in the hadron spectrum.

A relativistic supersymmetric quantum mechanics is proposed which uses Osp(1,4)\ensuremath{\supset}SO(3,2) for the spectrum and constrained Hamiltonian quantum mechanics for the dynamics of one-hadron systems. It combines baryon and meson towers into infinite supermultiplets in a way similar to the use of supersymmetries in nuclear physics. The predicted mass formula is fitted to the masses of baryon and meson resonances.

Dynamical supersymmetry U(12/4) for boson-fermion systems.

A supersymmetry scheme for nuclei, where neutron and proton bosons are distinguished, is presented. The single j for this scheme is assumed to be (3/2) and therefore the resulting supergroup is U(12/4). The dynamical supersymmetry investigated is the Spin(6) chain. This scheme is a direct generalization of the U(6/4) supersymmetry scheme previously proposed by Iachello and co-workers. Comparisons of the energies between the theory and experiment seem to suggest that such a supersymmetry U(12/4) may be found in certain regions in nuclei.

Hidden sector of superstring models: An effective lagrangian analysis

The effective lagrangian for the strongly interacting E 8-sector of superstring-type supergravity models is constructed. Dynamical supersymmetry breaking and other nonperturbative effects are analysed.

Accidental degeneracies and supersymmetric quantum mechanics

Some recently given examples of accidental degeneracies are shown to arise from an underlying supersymmetry. The appropriate dynamical supersymmetries are identified. The relevant spectrum-generating superalgebras for these supersymmetric quantum-mechanical systems are introduced and studied.

Dynamical supersymmetry breaking in a two-dimensional field theory

It is shown that a supersymmetric two-dimensional field theory with quartic fermion interactions can be dynamically broken. As a consequence the fermion field acquires mass.

Dynamical supersymmetry of the magnetic monopole and the 1/r 2-potential

We examine the recently discovered dynamical OSp(1, 1) supersymmetry of the Pauli Hamiltonian for a spin 1/2 particle with gyromagnetic ratio 2, in the presence of a Dirac magnetic monopole. Using this symmetry and algebraic methods only, we construct the spectrum and obtain the wave functions. At all but the lowest angular momenta, the states transform under a single irreducible representation of OSp(1, 1). On the lowest angular momentum states, it is impossible to define self-adjoint supercharges, and the states transform under an irreducible representation of SO(2, 1) only. The Hamiltonian is not self-adjoint in thes-wave sector, but admits a one parameter family of self-adjoint extensions. The full SO(2, 1) algebra can be realized only for two specific values of the parameter.

Spectroscopy of the platinum isotopes and the dynamical supersymmetry U(6/12).

The search for the U(6/12) dynamical supersymmetry in the platinum isotopes is presented. The data closely examined are the energy levels and B(E2)'s for the odd- and even-mass platinums. The systematics of the data indicate that there is evidence of underlying dynamical supersymmetry.

The experimental physics of dynamical supersymmetry in nuclei

Supersymmetry ideas for nuclei are outlined in the context of traditional models. Following this, a detailed discussion of the structure of two types of nuclear supersymmetry schemes, based on the U(6/4) and U(6/12) supergroups, is given along with an explanation of the appropriate empirical probes for testing each scheme. The experimental evidence for supersymmetry in nuclei is presented with emphasis on areas of both agreement and disagreement and with a discussion of alternate schemes that can reduce the latter.

Supersymmetry in nuclear physics

Applications of supersymmetry considerations to problems in nuclear physics are briefly reviewed. A few, selected, examples are discussed, and it is shown that experimental evidence supports the occurrence of dynamic supersymmetries in nuclear spectra.

Dynamical supersymmetry breaking in four dimensions and its phenomenological implications

It is now established that the non-renormalization theorems are violated by non-perturbative effects in many four-dimensional supersymmetric theories, and that dynamical supersymmetry-breaking (DSB) occurs in some chiral gauge theories. Here we presenr a set of general techniques which allow one to determine whether or not supersymmetry is broken in almost any theory, and permit a quite detailed analysis of the dynamics of many theories. These techniques are illustrated by analysis of a wide variety of instructive models, including one in which DSB occurs and in which we compute the spectrum and ground state energy. A careful discussion of the prospects for realistic model building is presented, including: an argument that additional gauge interactions are required to build realistic theories; dynamical supersymmetry-breaking in N = 1 supergravity theories; a detailed discussion of the problems and prospects for dynamical supersymmetry-breaking in the multi-TeV energy range.