12,949 research outputs found
On the cancellation of 4-derivative terms in the Volkov-Akulov action
Recently Kuzenko and McCarty observed the cancellation of 4-derivative terms
in the Volkov-Akulov supersymmetric action for the fermionic
Nambu-Goldstone field. Here is presented a simple algebraic proof of the
cancellation based on using the Majorana bispinors and Fiertz identities. The
cancellation shows a difference between the Volkov-Akulov action and the
effective superfield action recently studied by Komargodski and Seiberg and
containing one 4-derivative term. We find out that the cancellation effect
takes place in coupling of the Nambu-Goldstone fermion with the Dirac field.
Equivalence between the KS and the VA Lagrangians is proved up to the first
order in the interaction constant of the NG fermions.Comment: 18 pages; the version accepted for publication in Phys. Rev. D; new
section regarding the proof of the equivalence between the
Komargodski-Seiberg and the Volkov-Akulov actions is added: some comments and
new references are include
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
Supergravity before and after 1976
This paper is part of the lecture given at the TH Division of CERN and
devoted to the CXXV anniversary of the birthday of Elie Cartan (1869-1951). It
is shown how the methods of differential geometry, due to E. Cartan, were
applied to the construction of the supersymmetry transformation law and to the
actions for Goldstone fermions and supergravity.Comment: 8 pages, latex, CERN-TH.7226/9
The Tomonaga-Luttinger Model and the Chern-Simons Theory for the Edges of Multi-layer Fractional Quantum Hall Systems
Wen's chiral Tomonaga-Luttinger model for the edge of an m-layer quantum Hall
system of total filling factor nu=m/(pm +- 1) with even p, is derived as a
random-phase approximation of the Chern-Simons theory for these states. The
theory allows for a description of edges both in and out of equilibrium,
including their collective excitation spectrum and the tunneling exponent into
the edge. While the tunneling exponent is insensitive to the details of a
nu=m/(pm + 1) edge, it tends to decrease when a nu=m/(pm - 1) edge is taken out
of equilibrium. The applicability of the theory to fractional quantum Hall
states in a single layer is discussed.Comment: 15 page
Phenomenology of Goldstino Couplings
A general coupling of the Goldstino to the matter field and the weak
gravitational field is constructed based on the standard and the nonlinear
Volkov-Akulov realization of SUSY. The resulting Lagrangian, which is invariant
under SUSY transformations, can give rise to explicit interactions which couple
the helicity +-1/2 states of the gravitino with the gravitational field as well
as the matter field.Comment: 7 pages; final version to appear in Modern Physics Letters
Excited scalar mesons in a chiral quark model
First radial excitations of the isoscalar and isovector scalar mesons
f_0(400-1200), f_0(980) and a_0(980) are investigated in the framework of a
nonlocal version of a chiral quark model of the Nambu--Jona-Lasinio type. It is
shown that f_0(1370), f_J(1710) and a_0(1450) are the first radially excited
states of f_0(400-1200), f_0(980) and a_0(980) which are ground states of the
scalar meson nonet. The mesons' masses and strong decay widths are calculated.
The scalar resonance f_0(1500) is supposed to be a glueball. The status of
K_0^*(1430) is discussed.Comment: LaTeX, 1 figure, minor misprints eradicate
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