9,318 research outputs found
Gauging Nonlinear Supersymmetry
Coset methods are used to construct the action describing the dynamics
associated with the spontaneous breaking of the local supersymmetries. The
resulting action is an invariant form of the Einstein-Hilbert action, which in
addition to the gravitational vierbein, also includes a massive gravitino
field. Invariant interactions with matter and gauge fields are also
constructed. The effective Lagrangian describing processes involving the
emission or absorption of a single light gravitino is analyzed.Comment: 20 pages, no figure
Nonlinear Realizations of Supersymmetry and Other Symmetries
Simultaneous nonlinear realizations of spontaneously broken supersymmetry in
conjunction with other spontaneous and/or explicitly broken symmetries
including R symmetry, global chiral symmetry, dilatations and the
superconformal symmetries is reviewed.Comment: 15 pages, invited brief review for Mod. Phys. Lett.
Parafermions, parabosons and representations of so(\infty) and osp(1|\infty)
The goal of this paper is to give an explicit construction of the Fock spaces
of the parafermion and the paraboson algebra, for an infinite set of
generators. This is equivalent to constructing certain unitary irreducible
lowest weight representations of the (infinite rank) Lie algebra so(\infty) and
of the Lie superalgebra osp(1|\infty). A complete solution to the problem is
presented, in which the Fock spaces have basis vectors labelled by certain
infinite but stable Gelfand-Zetlin patterns, and the transformation of the
basis is given explicitly. We also present expressions for the character of the
Fock space representations
Nonabelian solutions in AdS_4 and d=11 supergravity
We consider solutions of the four dimensional Einstein-Yang-Mills system with
a negative cosmological constant , where is the nonabelian
gauge coupling constant. This theory corresponds to a consistent truncation of
gauged supergravity and may be uplifted to supergravity. A
systematic study of all known solutions is presented as well as new
configurations corresponding to rotating regular dyons and rotating nonabelian
black holes. The thermodynamics of the static black hole solutions is also
discussed. The generic EYM solutions present a nonvanishing magnetic flux at
infinity and should give us information about the structure of a CFT in a
background SU(2) field. We argue that the existence of these configurations
violating the no hair conjecture is puzzling from the AdS/CFT point of view.Comment: 52 pages; 24 figures; v2: minor changes, references added, version to
be published in PR
Singularities inside non-Abelian black holes
Singularities inside static spherically symmetric black holes in the SU(2)
Einstein-Yang-Mills and Einstein-Yang-Mills-dilaton theories are investigated.
Analytical formulas are presented describing oscillatory and power law metric
behavior near spacelike singularities in generic solutions.Comment: REVTeX, 9 pages, 2 EPS figures, uses epsf.st
Excitonic pairing between nodal fermions
We study excitonic pairing in nodal fermion systems characterized by a
vanishing quasiparticle density of states at the pointlike Fermi surface and a
concomitant lack of screening for long-range interactions. By solving the gap
equation for the excitonic order parameter, we obtain a critical value of the
interaction strength for a variety of power-law interactions and densities of
states. We compute the free energy and analyze possible phase transitions, thus
shedding further light on the unusual pairing properties of this peculiar class
of strongly correlated systems.Comment: 9 pages, 7 figures, minor revisions made, final versio
rho(omega)-> pi^0 pi^0 gamma, rho(omega) -> eta pi^0 gamma decays in the local quark Nambu--Jona-Lasinio model
The branching ratios and photon spectra of the rare processes rho(omega)->
pi^0 pi^0 gamma, rho(omega) -> eta pi^0 gamma are calculated in the framework
of the standard local quark Nambu--Jona-Lasinio (NJL) model. Three types of
diagrams are considered: the quark box and the pole diagrams with scalar
(sigma,a_0(980)) and vector (rho,omega) mesons. The obtained estimations for
the widths of the processes rho(omega)-> pi^0 pi^0 gamma are in satisfactory
agreement with existing experimental data. Predictions are made for the widths
of the processes rho(omega) -> eta pi^0 gamma.Comment: 6 pages, 5 figure
Production of pair in electron-positron annihilation in the Nambu-Jona-Lasinio model
The process is described in the framework of the
expanded NJL model in the energy region from 0.9 GeV to 1.5 GeV. The
contribution of intermediate state with vector mesons , and , where is the first radial
excitation of - meson was taken into account. Results obtained are in
satisfactory agreement with experimental data.Comment: 5 pages, 1 figure, 1 tabl
Gravitational-Recoil Effects on Fermion Propagation in Space-Time Foam
Motivated by the possible experimental opportunities to test quantum gravity
via its effects on high-energy neutrinos propagating through space-time foam,
we discuss how to incorporate spin structures in our D-brane description of
gravitational recoil effects in vacuo. We also point to an interesting
analogous condensed-matter system. We use a suitable supersymmetrization of the
Born-Infeld action for excited D-brane gravitational backgrounds to argue that
energetic fermions may travel slower than the low-energy velocity of light:
\delta c / c \sim -E/M. It has been suggested that Gamma-Ray Bursters may emit
pulses of neutrinos at energies approaching 10^{19} eV: these would be
observable only if M \gsim 10^{27} GeV.Comment: 18 pages LaTe
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