Using the Einstein-Cartan-Dirac theory, we study the effect of torsion on neutrino oscillation. We see that torsion cannot induce neutrino oscillation, but affects it whenever oscillation exists for other reasons. We show that the torsion effect on neutrino oscillation is as important as the neutrino mass effect, whenever the ratio of neutrino number density to neutrino energy is ∼ 10 cm−3 /eV,...

In the framework of the teleparallel equivalent of general relativity, we study the dynamics of a gravitationally coupled electromagnetic field. It is shown that, besides being able to be minimally coupled to torsion, the electromagnetic field, through its energy–momentum tensor, is also able to produce torsion. Furthermore, it is shown that this kind of coupling of the electromagnetic field wi...

Oscillating phases in Bianchi type IX anisotropic universes are obtained as linearized solutions of Einstein-Cartan theory of gravity.Instead of making use of Weyssenhoff spinning fluids we addopt axionic torsion matter where the torsion tensor is totally skew-symmetric as in Kalb-Rammond type theories.Spin-torsion,metric and matter density oscillate at different phases. An upper bound oscillat...

Motivated by conventional gauge theories, we consider a theory of gravity in which the Einstein–Hilbert action is replaced by a term that is quadratic in the Riemann tensor. We focus on cosmological solutions to the field equations in flat, open and closed universes. The gravitational action is scale invariant, so the only matter source considered is radiation. The theory can also accommodate i...

The theory of distributions in non-Riemannian spaces is used to obtain exact static thin domain wall solutions of Einstein-Cartan equations of gravity. Curvature δ-singularities are found while Cartan torsion is given by Heaviside functions. Weitzenböck planar walls are caracterized by torsion δ-singularities and zero curvature. It is shown that Weitzenböck static thin domain walls do not exist...

We present a review of some recent models of gravitation theory with propagating torsion based on the use of a torsion-dilaton field and propose one more model of this type which promises to be more realistic. A proper universal self-consistent minimal action principle yields the properties of this model and predicts the interactions of torsion-dilaton field with the real matter. The new model ...

The possibility of parity violation in a gravitational theory with torsion is extensively explored in four and higher dimensions. In the former case, we have listed our conclusions on when and whether parity ceases to be conserved, with both two-and three-index antisymmetry of the torsion field. In the latter, the bulk spacetime is assumed to have torsion, and the survival of parity-violating t...

We classify 7-dimensional cocalibrated G2-manifolds with parallel characteristic torsion and non-abelian holonomy. All these spaces admit a metric connection ∇ with totally skew-symmetric torsion and a spinor field Ψ1 solving the equations in the common sector of type II superstring theory. There exist G2-structures with parallel characteristic torsion that are not naturally reductive. 1. Metri...

We present a gauge theory of the conformal group in four spacetime dimensions with non-vanishing torsion. In particular, we allow for completely antisymmetric torsion, equivalent by Hodge duality to an axial vector whose presence does not spoil invariance theory, contrast claims antecedent literature. The requirement implies differential condition (in Killing equation) on aforementioned which l...

Let τ be a hereditary torsion theory on ModR and suppose that Qτ : ModR → ModR is the localization functor. It is shown that for all R-modules M, every higher derivation defined on M can be extended uniquely to a higher derivation defined on Qτ(M) if and only if τ is a higher differential torsion theory. It is also shown that if τ is a TTF theory and Cτ : M →M is the colocalization functor, the...