2,289 research outputs found
Bosonized noncommutative bi-fundamental fermion and S-duality
We perform the path-integral bosonization of the recently proposed
noncommutative massive Thirring model (NCMT) [JHEP0503(2005)037]. This
model presents two types of current-current interaction terms related to the
bi-fundamental representation of the group U(1). Firstly, we address the
bosonization of a bi-fundamental free Dirac fermion defined on a noncommutative
(NC) Euclidean plane \IR_{\theta}^{2}. In this case we show that the fermion
system is dual to two copies of the NC Wess-Zumino-Novikov-Witten model. Next,
we apply the bosonization prescription to the NCMT model living on
\IR_{\theta}^{2} and show that this model is equivalent to two-copies of the
WZNW model and a two-field potential defined for scalar fields corresponding to
the global symmetry plus additional bosonized terms for the
four fermion interactions. The bosonic sector resembles to the one proposed by
Lechtenfeld et al. [Nucl. Phys. B705(2005)477] as the noncommutative
sine-Gordon for a {\sl pair} of scalar fields. The bosonic and fermionic
couplings are related by a strong-weak duality. We show that the couplings of
the both sectors for some representations satisfy similar relationships up to
relevant re-scalings, thus the NC bi-fundamental couplings are two times the
corresponding ones of the NC fundamental (anti-fundamental) and eight times the
couplings of the ordinary massive Thirring and sine-Gordon models.Comment: 18 pages, LaTex. References added. A general product has been considered in the conclusion section . Version to appear in
JHE
Generalized sine-Gordon/massive Thirring models and soliton/particle correspondences
We consider a real Lagrangian off-critical submodel describing the soliton
sector of the so-called conformal affine Toda model coupled to
matter fields (CATM). The theory is treated as a constrained system in the
context of Faddeev-Jackiw and the symplectic schemes. We exhibit the parent
Lagrangian nature of the model from which generalizations of the sine-Gordon
(GSG) or the massive Thirring (GMT) models are derivable. The dual description
of the model is further emphasized by providing the relationships between
bilinears of GMT spinors and relevant expressions of the GSG fields. In this
way we exhibit the strong/weak coupling phases and the (generalized)
soliton/particle correspondences of the model. The case is also
outlined.Comment: 22 pages, LaTex, some comments and references added, conclusions
unchanged, to appear in J. Math. Phy
Gauge Invariant Extension of Linearized Horava Gravity
In the present paper we have constructed a gauge invariant extension of a
generic Horava Gravity (HG) model (with quadratic curvature terms) in
linearized version in a systematic procedure. No additional fields are
introduced. The linearized HG model is explicitly shown to be a gauge fixed
version of the Einstein Gravity (EG) thus proving the Bellorin-Restuccia
conjecture in a robust way. In the process we have explicitly computed the
correct Hamiltonian dynamics using Dirac Brackets appearing from the Second
Class Constraints present in the HG model. We comment on applying this scheme
to the full non-linear HG.Comment: 11 pages, no figures, some changes in the text but no change in the
results, Journal reference: Mod. Phys. Lett. A, Vol. 26, No. 37 (2011) pp.
279
Counterterms in semiclassical Horava-Lifshitz gravity
We analyze the semiclassical Ho\v{r}ava-Lifshitz gravity for quantum scalar
fields in 3+1 dimensions. The renormalizability of the theory requires that the
action of the scalar field contains terms with six spatial derivatives of the
field, i.e. in the UV, the classical action of the scalar field should preserve
the anisotropic scaling symmetry ( ,
with ) of the gravitational action. We discuss the renormalization
procedure based on adiabatic subtraction and dimensional regularization in the
weak field approximation. We verify that the divergent terms in the adiabatic
expansion of the expectation value of the energy-momentum tensor of the scalar
field contain up to six spatial derivatives, but do not contain more than two
time derivatives. We compute explicitly the counterterms needed for the
renormalization of the theory up to second adiabatic order and evaluate the
associated functions in the minimal subtraction scheme.Comment: 8 page
Higher Grading Conformal Affine Toda Teory and (Generalized) Sine-Gordon/Massive Thirring Duality
Some properties of the higher grading integrable generalizations of the
conformal affine Toda systems are studied. The fields associated to the
non-zero grade generators are Dirac spinors. The effective action is written in
terms of the Wess-Zumino-Novikov-Witten (WZNW) action associated to an affine
Lie algebra, and an off-critical theory is obtained as the result of the
spontaneous breakdown of the conformal symmetry. Moreover, the off-critical
theory presents a remarkable equivalence between the Noether and topological
currents of the model. Related to the off-critical model we define a real and
local Lagrangian provided some reality conditions are imposed on the fields of
the model. This real action model is expected to describe the soliton sector of
the original model, and turns out to be the master action from which we uncover
the weak-strong phases described by (generalized) massive Thirring and
sine-Gordon type models, respectively. The case of any (untwisted) affine Lie
algebra furnished with the principal gradation is studied in some detail.
The example of is presented explicitly.Comment: 28 pages, JHEP styl
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