NONCOMMUTATIVE GEOMETRY, GEOMETRICAL ASPECTS OF SKYRMIONS AND STRING THEORY
It is pointed out here that noncommutative geometry having the space–time manifold X = M4 × Z2 leads to the description of a massive fermion as a skyrmion when the discrete space–time is incorporated as an internal variable. The inherent anisotropic feature of the internal space gives rise to the Skyrme term as well as the Wess–Zumino term. An array of such skyrmions may be considered as a three-dimensional Ising system. It is shown that the composite system of such skyrmions may be viewed as the (3 + 1)-dimensional relative of the Polyakov string theory when the associated Liouville field corresponds to the attachment of topological fixtures like vortex lines at the end points of an open string. These two systems are found to satisfy certain duality principles through conformal duality which are similar to T duality and S duality in conventional string picture.

title: QUANTUM HALL SKYRMIONS IN THE FRAMEWORK OF O(4) NONLINEAR SIGMA MODEL
abstract: A new framework for quantum Hall skyrmions in O(4) nonlinear sigma model is studied here. The size and energy of the skyrmions are determined incorporating the quartic stability term in the Lagrangian. Moreover, the introduction of a θ-term determines the spin and statistics of these skyrmions.

title: EXTENDED CONFORMAL GROUP, SUPERSYMMETRY, AND GEOMETRICAL PROPERTIES OF HADRONS
abstract: We have studied the interrelation among conformal symmetry, internal symmetry and super-symmetry and have shown that extended conformal group which includes, apart from conformal transformation, space, time and conformal reflection can give rise to internal symmetry algebra as well as supersymmetry algebra. To achieve this result, we have dealt with conformal spinors which are taken to be the constituents of the hadrons and these split into two Cartan semispinors or Dirac spinors in the Minkowski space, giving rise to the particle and antiparticle configurations. Supersymmetry is broken here just by the mass term and as such no massless hadron can exist in nature. The internal symmetry arises from the discrete symmetry of reflection. The most significant feature of this formalism is that the symmetry structure helps us to explain the meson-baryon mass difference in an elegant way and the role of fictitious superpartners is completely avoided. Again, any baryon number nonconserving process like proton decay is found to be forbidden by the Lorentz invariance. Finally, it is noted that though the discrete symmetry of reflection is taken to be the origin of the internal symmetry, topological nontrivial structures like strings do not appear here and this also avoids the possibility of the nonconservation of global charge.

title: Random fields, ising model and bosson-fermion phase transition
abstract: SummaryIt is here shown that when the stochastic quantization procedure is introduced to a massive Thirring fermion where the latter is described as a bound state of massless oscillators interacting through a gradient term in a linear chain, we find that a boson-fermion phase transition occurs at a critical temperatureT =Tc, and atT >Tc supersymmetry is restored. In this scheme supersymmetry is broken by the generation of mass which arises due to the presence of the gradient term.

title: Geometrical aspects of magnetic monopoles
abstract: The possible topological structures of elementary particles have been investigated to explore the possibility of the existence of magnetic monopoles. It is pointed out that when an elementary charged particle is depicted as an extended body such that the orientation of the internal space (“internal helicity”) defines the fermion number, the global conservation of this does not allow the existence of a magnetic monopole. Again it is argued that when anisotropy is introduced in the microlocal space-time depicting the internal space of hadrons, this gives rise to the internal symmetry algebra and no non-Abelian gauge fields and Higgs scalars are necessary to have a grand unified scheme of interactions. This avoids theSU2 and GUT monopoles. Besides, in this formalism, baryon number corresponds to the orientation or internal helicity of the composite system and the global conservation of this quantum number is found to be a consequence of Lorentz invariance. This forbids the existence of any sort of cosmological monopole in this Lorentz invariant Universe.

title: A LIE GROUP FRAMEWORK FOR COMPOSITE PARTICLES AND HARMONIC OSCILLATOR MASS SPECTRUM
abstract: A harmonic oscillator mass spectrum is developed through a relativistic covariant method in unifying the external and internal variables of a hadron leading to a dynamical Lie algebra. It is shown that through the introduction of an internal variable ξμ, which behaves as a 'direction vector', attached to each space-time point, χμ, and the spatial extension, Xi, of the composite system, we can uniquely determine a harmonic oscillator mass spectrum. This is valid even when the constituents are taken to be massless. Moreover, when these internal variables are associated with the internal symmetry, the mass splitting due to the internal symmetry breaking is incorporated in this formalism and no adhoc consideration is necessary. The mass spectrum of the neutral isovector and isoscalar mesons is computed in this framework.

title: Associated Higgs production in CP-violating supersymmetry: Probing the 'open hole' at the large hadron collider
abstract: A benchmark CP-violating supersymmetric scenario (known in the literature as 'CPX-scenario') is studied in the context of the Large Hadron Collider (LHC). It is shown that the LHC, with low to moderate accumulated luminosity, will be able to probe the existing 'hole' in the m{sub h{sub 1}}-tan{beta} plane, which cannot be ruled out by the Large Electron Positron Collider data. This can be done through associated production of Higgs bosons with top quark and top squark pairs leading to the signal dilepton+ {<=}5 jets (including 3b-jets)+missing p{sub T}. Efficient discrimination of such a CP-violating supersymmetric scenario from other contending ones is also possible at the LHC with a moderate volume of data.

title: Signatures of gaugino mass non-universality in cascade Higgs production at the LHC
abstract: Supersymmetric cascades, involving charginos and neutralinos at various stages, contribute in a significant way to Higgs production at the LHC. We explore the nature of such cascades, completely relaxing the universality of the gaugino masses. It is found that the deviation from the scenario with universal gaugino masses would be reflected in the relative production rates for the lightest neutral Higgs and the charged Higgses.

title: Higgs production in CP-violating supersymmetric cascade decays: probing the ‘open hole’ at the Large Hadron Collider
abstract: A benchmark CP-violating supersymmetric scenario (known as ‘CPX-scenario’ in the literature) is studied in the context of the Large Hadron Collider (LHC). It is shown that the LHC, with low to moderate accumulated luminosity, will be able to probe the existing ‘hole’ in the $ {m_{{h_1}}} $-tan β plane, which cannot be ruled out by the LEP data. We explore the parameter space with cascade decay of third generation squarks and gluino with CP-violating decay branching fractions. We propose a multi-channel analysis to probe this parameter space some of which are background free at an integrated luminosity of 5-10 fb−1. Specially, multi-lepton final states (3l, 4l and like sign di-lepton) are almost background free and have 5σ reach for the corresponding signals with very early data of LHC for both 14 TeV and 7 TeV center of mass energy.

title: Displaced Higgs production in type III seesaw
abstract: We point out that the type III seesaw mechanism introducing fermion triplets predicts peculiar Higgs boson signatures of displaced vertices with two b jets and one or two charged particles which can be cleanly identified. In a supersymmetric theory, the scalar partner of the fermion triplet contains a neutral dark matter candidate which is almost degenerate with its charged components. A Higgs boson can be produced together with such a dark matter triplet in the cascade decay chain of a strongly produced squark or gluino. When the next lightest supersymmetric particle (NLSP) is bino/wino-like, there appears a Higgs boson associated with two charged tracks of a charged lepton and a heavy charged scalar at a displacement larger than about 1 mm. The corresponding production cross-section is about 0.5 fb for the squark/gluino mass of 1 TeV. In the case of the stau NLSP, it decays mainly to a Higgs boson and a heavy charged scalar whose decay length is larger than 0.1 mm for the stau NLSP mixing with the left-handed stau smaller than 0.3. As this process can have a large cascade production ∼2 pb for the squark/gluino mass ∼1 TeV, one may be able to probe it at the early stage of the LHC experiment.

title: Probing non-universal gaugino masses via Higgs boson production under SUSY cascades at the LHC: a detailed study
abstract: Cascade decays of Supersymmetric (SUSY) particles are likely to be prolific sources of Higgs bosons at the Large Hadron Collider (LHC). In this work, we explore, with the help of detailed simulation, the role of non-universal gaugino masses in the production of the Higgs bosons under SUSY cascades. The analysis is carried out by choosing an appropriate set of benchmark points with non-universal gaugino masses in the relevant SUSY parameter space and then contrasting the resulting observations with the corresponding cases having universal relationship among the same. It is shown that even of data at an early phase of the LHC-run with 10 fb−1 one would be able to see, under favourable situations, the imprint of non-universal gaugino masses by reconstructing various Higgs boson resonances and comparing their rates. With increased accumulated luminosities, the indications would naturally become distinct over a larger region of the parameter space.