120591896
A note on supersymmetry and magnetic fields
ConclusionIn the present article we have considered two supersymmetric non-abelian gauge theories in the presence of an external magnetic field. In has been shown that the effect of the magnetic field breaks suppersymmetry at the one-loop level; however, if supersymmetry is already broken spontaneously at the tree level, then the magnetic field effect does not restore it at the one-loop level. These facts could be used in SUSY GUT models (which are used to describe the early universe), to study phase transition in those models.
121137215
Novel perturbation expansion for the Langevin equation
We discuss the randomly driven systemdx/dt= -W(x) +f(t), wheref(t) is a Gaussian random function or stirring force with〈f(t)f(t′)〉=2δ(t−t′), andW(x) is of the formgx1+2δ. The parameterδ is a measure of the nonlinearity of the equation. We show how to obtain the correlation functions〈x(t)f(t′)〉···x(t(n))〉f as a power series inδ. We obtain three terms in theδ expansion and show how to use Padé approximants to analytically continue the answer in the variableδ. By using scaling relations, we show how to get a uniform approximation to the equal-time correlation functions valid for allg andδ.
8406718
Motion of a spin-½ particle in shape invariant scalar and magnetic fields
We study the motion of a spin-½ particle in a scalar as well as a magnetic field within the framework of supersymmetric quantum mechanics. We also introduce the concept of shape invariant scalar and magnetic fields and it is shown that the problem admits exact analytical solutions when such fields are considered.
120571457
Supersymmetric anyon quantum mechanics
Abstract We develop a framework for anyons within supersymmetric quantum mechanics. We prove that supersymmetry can be realized spectrally but necessarily requires a contact interaction which modifies in a specific way the usual regularity condition of the wavefunction at the origin.
122355855
Comment on the ''Effect of a strong magnetic field and high temperature on broken gauge theories''
In a recent paper Chakrabarti has examined the effects of a strong magnetic field and high temperature on spontaneously broken gauge theories. We point out the invalidity of the approximation he has used to evaluate the one-loop effective potential. Using a rigorous and improved method, we obtain a result different from Chakrabarti's result. Further using this method we extend the results of the aforementioned paper by including fermions in the theory.
119312840
'Stringy' Coherent States Inspired By Generalized Uncertainty Principle
Abstract Coherent States with Fractional Revival property, that explicitly satisfy the Generalized Uncertainty Principle (GUP), have been constructed in the context of Generalized Harmonic Oscillator. The existence of such states is essential in motivating the GUP based phenomenological results present in the literature which otherwise would be of purely academic interest. The effective phase space is Non-Canonical (or Non-Commutative in popular terminology). Our results have a smooth commutative limit, equivalent to Heisenberg Uncertainty Principle. The Fractional Revival time analysis yields an independent bound on the GUP parameter. Using this and similar bounds obtained here, we derive the largest possible value of the (GUP induced) minimum length scale. Mandel parameter analysis shows that the statistics is Sub-Poissonian. Correspondence Principle is deformed in an interesting way. Our computational scheme is very simple as it requires only first order corrected energy values and undeformed basis states.
17998522
Constraining four neutrino mass patterns from neutrinoless double beta decay
All existing data on neutrino oscillations (including those from the LSND experiment) imply a four neutrino scheme with six different allowed mass patterns. Some of the latter are shown to be disfavored by using a conservative upper bound on the ββ0ν nuclear decay rate, if neutrinos are assumed to be Majorana particles. Comparisons are also made with restrictions from tritium β-decay and cosmology.
119693459
Radiatively broken symmetries of nonhierarchical neutrinos
Symmetry-based ideas, such as the quark-lepton complementarity principle and the tribimaximal mixing scheme, have been proposed to explain the observed mixing pattern of neutrinos. We argue that such symmetry relations need to be imposed at a high scale {lambda}{approx}10{sup 12} GeV characterizing the large masses of right-handed neutrinos required to implement the seesaw mechanism. For nonhierarchical neutrinos, renormalization group evolution down to a laboratory energy scale {lambda}{approx}10{sup 3} GeV tends to radiatively break these symmetries at a significant level and spoil the mixing pattern predicted by them. However, for Majorana neutrinos, suitable constraints on the extra phases {alpha}{sub 2,3} enable the retention of those high scale mixing patterns at laboratory energies. We examine this issue within the minimal supersymmetric standard model and demonstrate the fact posited above for two versions of quark-lepton complementarity and two versions of tribimaximal mixing. The appropriate constraints are worked out for all these four cases. Specifically, a preference for {alpha}{sub 2}{approx_equal}{pi} (i.e., m{sub 1}{approx_equal}-m{sub 2}) emerges in each case. We also show how a future accurate measurement of {theta}{sub 13} may enable some discrimination among these four cases in spite of renormalization group evolution.
122119900
Unitarity limit on the gaugino-gravitino mass ratio
Abstract The imposition of tree-level unitarity at all energies upto the Planck scale on the amplitude for the scattering of two gauge bosons into two gravitinos is shown to put an upper bound on the ratio between gaugino and gravitino masses. The absolute masses of the lightest gauge singlet scalar and pseudoscalar bosons are also bounded from above.
121475270
Compositeness Resolution of the Higgs Boson
An experimental study of the process ee-bar..-->..Z..-->..H..mu..mu-bar (for a Higgs boson H with a mass m/sub H/ less than 40 GeV) is likely to reveal the structure of the ZHZ* vertex. It is shown how this may help resolve the question of the compositeness of H.
14038906
Bilarge neutrino mixing from supersymmetry with high scale nonrenormalizable interactions
We suggest a supersymmetric (SUSY) explanation of neutrino masses and mixing, where nonrenormalizable interactions in the hidden sector generate lepton number violating Majorana mass terms for both right-chiral sneutrinos and neutrinos. It is found necessary to start with a superpotential including an array of gauge singlet chiral superfields. This leads to nondiagonal ΔL=2 mass terms and almost diagonal SUSY breaking A-terms. As a result, the observed pattern of bilarge mixing can be naturally explained by the simultaneous existence of the seesaw mechanism and radiatively induced masses. Allowed ranges of parameters in the gauge singlet sector are delineated, corresponding to each of the cases of normal hierarchy, inverted hierarchy, and degenerate neutrinos.