4 papers · 1 filter
Quantum Effects in the Spacetime of a Magnetic Flux Cosmic String
M. E. X. Guimaraes, A. L. N. Oliveira
In this work we compute the vacuum expectation values of the energy-momentum tensor and the average value of a massive, charged scalar field in the presence of a magnetic flux cosm…
Breakdown of the Mechanism of Forming Wakes by a Current-Carrying String
A. L. N. Oliveira, M. E. X. Guimaraes
In this letter, we emphasize the effect that the inclusion of a electromagnetic properties for a string brings logarithmic divergences to the accretion problem and the formation an…
Wakes in Dilatonic Current-Carrying Cosmic Strings
A. L. N. Oliveira, M. E. X. Guimaraes
In this work, we present the gravitational field generated by a cosmic string carrying a timelike current in the scalar-tensor gravities. The mechanism of formation and evolution o…
A New Version of Dirac's AEther and Its Cosmological Applications
Marcelo Carvalho, A. L. Oliveira
We propose a new formulation for the AEther of Dirac based on a lagrangian approach. We analyse how the presence of a particular self-interaction term in the lagrangian lead us to…