A. F. Ferrari

Lorentz violation in the linearized gravity

Abstract We study some physical consequences of the introduction of a Lorentz-violating modification term in the linearized gravity, which leads to modified dispersion relations for gravitational waves in the vacuum. We discuss two possible mechanisms for the induction of such a term in the Lagrangian. First, it is generated at the quantum level by a Lorentz-breaking coupling of the gravity field to a spinor field. Second, it appears as consequence of a particular modification of the Poisson algebra of the canonical variables, in the spirit of the so-called “noncommutative fields approach”.

Three-dimensional nonanticommutative superspace

We propose two alternative formulations for a three-dimensional nonanticommutative superspace in which some of the fermionic coordinates obey Clifford anticommutation relations. For this superspace, we construct the supersymmetry generators satisfying standard anticommutation relations and the corresponding supercovariant derivatives. We formulate a scalar superfield theory in such a superspace and calculate its propagator. We also suggest a prescription for the introduction of interactions in such theories.

Superfield covariant analysis of the divergence structure of noncommutative supersymmetric QED/sub 4/

Commutative supersymmetric Yang-Mills is known to be renormalizable for

Spontaneous gauge symmetry breaking in a supersymmetric Chern-Simons model

{cal N} = 1, 2

Supersymmetric non-Abelian non-commutative Chern–Simons theory

, while finite for

Lorentz symmetry breaking in the noncommutative Wess-Zumino model : One loop corrections

{cal N} = 4

Finiteness of the noncommutative supersymmetric Maxwell-Chern-Simons theory

. However, in the noncommutative version of the model (NCSQED

Duality of three-dimensional superfield theories

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Perturbative finiteness of three-dimensional supersymmetric QED to all orders

) the UV/IR mechanism gives rise to infrared divergences which may spoil the perturbative expansion. In this work we pursue the study of the consistency of NCSQED

The supersymmetric (2 + 1)D noncommutative CP(N−1) model in the fundamental representation

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