Marco Maceda

The Noncommutative Ward Metric

We analyze the moduli-space metric in the static non-Abelian charge-two sector of the Moyal-deformed CP 1 sigma model in 1 + 2 dimensions. After carefully reviewing the commutative results of Ward and Ruback, the noncommutative Kahler potential is expanded in powers of dimensionless moduli. In two special cases we sum the perturbative series to analytic expressions. For any nonzero value of the noncommutativity parameter, the logarithmic singularity of the commutative metric is expelled from the origin of the moduli space and possibly altogether.

Thermodynamics of a Higher Dimensional Noncommutative Inspired Anti-de Sitter-Einstein-Born-Infeld Black Hole

We analyze noncommutative deformations of a higher dimensional anti-de Sitter-Einstein-Born-Infeld black hole. Two models based on noncommutative inspired distributions of mass and charge are discussed and their thermodynamical properties such as the equation of state are explicitly calculated. In the (3 + 1)-dimensional case the Gibbs energy function of each model is used to discuss the presence of phase transitions.

Noncommutative Dirac quantization condition using the Seiberg-Witten map

We investigate the validity of the Dirac quantization condition (DQC) for magnetic monopoles in noncommutative space-time. We use an approach based on an extension of the method introduced by Wu and Yang; the effects of noncommutativity are analyzed using the Seiberg-Witten map and the corresponding deformed Maxwells equations are discussed. By means of a perturbation expansion in the noncommutativity parameter

Non-commutative BTZ space-time

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Exact BPS bound for noncommutative baby Skyrmions

, we show first that the DQC remains unmodified up to the first and second order. This result is then generalized to all orders in the expansion parameter for a class of noncommutative electric currents induced by the Seiberg-Witten map; these currents reduce to the Dirac delta function in the commutative limit.

S{sup 1}xS{sup 2} Gowdy supersymmetric constraint

A non-commutative model of BTZ space-time is introduced using deformed relations in phase space. Consequences of this on the classical BTZ solution are discussed.

The Kähler Potential of the Non‐commutative CP1 model

Abstract The noncommutative baby Skyrme model is a Moyal deformation of the two-dimensional sigma model plus a Skyrme term, with a group-valued or Grassmannian target. Exact abelian solitonic solutions have been identified analytically in this model, with a singular commutative limit. Inside any given Grassmannian, we establish a BPS bound for the energy functional, which is saturated by these baby Skyrmions. This asserts their stability for unit charge, as we also test in second-order perturbation theory.

Gravitational waves in non‐commutative geometry: effects upon polarization

We obtain the supersymmetric constraint for S{sup 1}xS{sup 2} Gowdy spacetime in the N=1 supergravity formalism of quantum cosmology in four dimensions. The physical states of the model for both polarized and unpolarized cases are presented.

On the non-commutative CP{sup 1} model

We present some results on the moduli space for the charge two‐soliton solution of the non‐commutative CP1 model. The associated Kahler potential and its relation to the commutative case are discussed.

Comment on 'Scattering amplitudes and thermal temperatures of the Schwarzschild-de Sitter black holes'

In the present work we consider some of the effects of gravitational waves emerging from a scenario in which geometry has lost its commutative character. In particular we evaluate the effects of non‐commutativity upon the polarization of the corresponding waves. These results are then employed in order to put forward some tests, that could allow us to fix experimental bounds to the non‐commutative parameters.