Geometrical CP violation in multi-Higgs models

We introduce several methods to obtain calculable phases with geometrical values that are independent of arbitrary parameters in the scalar potential. These phases depend on the number of scalars and on the order of the discrete non-Abelian group considered. Using these methods we present new geometrical CP violation candidates with vacuum expectation values that must violate CP (the transformation that would make them CP conserving is not a symmetry of the potential). We also extend to non-renormalisable potentials the proof that more than two scalars are needed to obtain these geometrical CP violation candidates.Comment: 8 pages, 2 figures. v2: table added, accepted by JHE

Controle biológico da traça-do-tomateiro em sistema orgânico de produção.

bitstream/item/103050/1/bpd-52.pd

Os conselhos de contribuintes como espaços democráticos : um exercício de cidadania fiscal

Aborda os desafios e limites da participação e deliberação sociopolítica envolvendo Estado e sociedade, com enfoque no efetivo controle social exercido pelos conselhos de contribuintes que, em esfera municipal de governo, limitam a atuação estatal, promovendo o exercício de cidadania fiscal

Causal Structure and Birefringence in Nonlinear Electrodynamics

We investigate the causal structure of general nonlinear electrodynamics and determine which Lagrangians generate an effective metric conformal to Minkowski. We also proof that there is only one analytic nonlinear electrodynamics presenting no birefringence.Comment: 11 pages, no figure