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- Ricardo Amorim
- Physical review letters
- 2008

Some consequences of promoting the object of noncommutativity theta(ij) to an operator in Hilbert space are explored. Its canonical conjugate momentum is also introduced. Consequently, a consistent algebra involving the enlarged set of canonical operators is obtained, which permits us to construct theories that are dynamically invariant under the action of… (More)

- Ricardo Amorim
- 2008

In the present work we study dynamical space-time symmetries in noncommutative relativistic theories by using the minimal canonical extension of the Doplicher, Fredenhagen and Roberts algebra. Our formalism is constructed in an extended space-time with independent degrees of freedom associated with the object of noncommutativity θ . In this framework we… (More)

We show that the massive noncommutative U(1) can be embedded in a gauge theory by using the BFFT Hamiltonian formalism. By virtue of the peculiar non-Abelian algebraic structure of the noncommutative massive U(1) theory, several specific identities involving Moyal commutators had to be used in order to make the embedding possible. This leads to an infinite… (More)

- Ricardo Amorim
- 2009

By using a framework where the object of noncommutativity θ represents independent degrees of freedom, we study the symmetry properties of an extended x + θ space-time, given by the group P ’, which has the Poincaré group P as a subgroup. In this process we use the minimal canonical extension of the Doplicher, Fredenhagen and Roberts algebra. It is also… (More)

- Ricardo Amorim
- 2008

A consistent classical mechanics formulation is presented in such a way that, under quantization, it gives a noncommutative quantum theory with interesting new features. The Dirac formalism for constrained Hamiltonian systems is strongly used, and the object of noncommutativity θ plays a fundamental rule as an independent quantity. The presented classical… (More)

We implement the Hamiltonian treatment of a nonAbelian noncommutative gauge theory, considering with some detail the algebraic structure of the noncommutative symmetry group. The first class constraints and Hamiltonian are obtained and their algebra derived, as well as the form of the gauge invariance they impose on the first order action. In recent years… (More)

In this work we analyze complex scalar fields using a new framework where the object of noncommutativity θ represents independent degrees of freedom. In a first quantized formalism, θ and its canonical momentum πμν are seen as operators living in some Hilbert space. This structure is compatible with the minimal canonical extension of the… (More)

- R Amorim, J Barcelos-Neto
- 2008

We study an extension of the axial model where local gauge symmetries are taken into account. The anomaly of the axial current is calculated by the Fujikawa formalism and the model is also solved. Besides the well known features of the particular models (axial and Schwinger) it was obtained an effective interaction of scalar and gauge fields via a… (More)

- Ricardo Amorim, Jorge Facão, João C. Rodrigues, Maria João Carvalho, Luis Godinho, Pedro Graça
- 2015

In Figure 1 a schematic presentation of the combistore is shown. This figure also shows the flow direction for each port and the used ports. In order to study the configuration of the inner storage tank, used for DHW pre-heating or as back-up of the space heating, tests according to EN 12977-3:2012 [2] were performed. Tests according to EN 12977-4:2012 [2]… (More)