Gauge Theory Of Gravity Research Articles

On the Higgs feature of gravity

The gauge gravitation theory, based on the equivalence principle besides the gauge principle, is formulated in the fibre bundle terms. The correlation between gauge geometry on spinor bundles describing Dirac fermion fields and space-time geometry on a tangent bundle is investigated. We show that field functions of fermion fields in presence of different gravitational fields are always written with respect to different reference frames. Therefore, the conventional quantization procedure is applicable to fermion fields only if gravitational field is fixed. Quantum gravitational fields violate the above mentioned correlation between two geometries.

Belinfante type invariance of the Noether identities in a riemannian and a Weitzenböck spacetime

The energy-momentum and angular momentum Noether identities for a matter field in the Minkowski spacetime of special relativity are invariant under a relocalization of their canonical currents by means of superpotentials. We extend this invariance for the angular momentum identity to the Riemann-Cartan spacetime of the Poincaré gauge theory of gravity (PGT). For the energy-momentum identity we find sufficient conditions which guarantee appropriate relocalization in a Riemannian and in a Weitzenböck spacetime. In particular, we recover the symmetric, divergence-free Belinfante-Rosenfeld energy-momentum current of general relativity.

Extended Spinor Structure and Exotic Spinor Field in \overlinePoincare Gauge Theory of Gravity

Extended Spinor Structure and Exotic Spinor Field in \overlinePoincare Gauge Theory of Gravity

A Supersymmertic Lagrangian for Poincaré Gauge Theories of Gravity

A Supersymmertic Lagrangian for Poincaré Gauge Theories of Gravity

Progress in metric-affine gauge theories of gravity with local scale invariance

Einstein's general relativity theory describes very well the gravitational phenomena in themacroscopic world. In themicroscopic domain of elementary particles, however, it does not exhibit gauge invariance or approximate Bjorken type scaling, properties which are believed to be indispensible for arenormalizable field theory. We argue that thelocal extension of space-time symmetries, such as of Lorentz and scale invariance, provides the clue for improvement. Eventually, this leads to aGL(4, R)-gauge approach to gravity in which the metric and the affine connection acquire the status ofindependent fields. The Yang-Mills type field equations, the Noether identities, and conformal models of gravity are discussed within this framework. After symmetry breaking, Einstein's GR surfaces as an effective “low-energy” theory.

Strength of the Poincaré gauge field equations in first order formalism

The Yang-Mills type field equations of the Poincaré gauge theory of gravity are analyzed for their “strength” in the sense of Einstein. In a d-dimensional spacetime we find for the corresponding “index” the surprisingly simple expression S PG = ( d + 1) d( d − 1) ( d − 2). This is a new result following from a corresponding formula for general Yang-Mills systems.

VIERBEIN IN DE SITTER GAUGE THEORY OF GRAVITY

In the gauge theory of gravity, SO'(5) gauge fields are shown to be related to vierbein and spin connection by a form of gauge transformation with the transformation matrix parametrized by an S4 unit vector [Formula: see text]. It is understood as the collective coordinate parametrizing the vacuum solution of maximal symmetric space. The action of pure gravity theory is determined uniquely (up to surface term) by the requirement that the pure gauge configuration of SO'(5) gauge fields gives the maximally symmetric solution of the equation of motion, i.e., de Sitter space of constant curvature.

Is the Poincare group a suitable gauge group for gravity

We argue that, instead of the Poincare group, the U(1)×SU(2) group generated by the quantum numbers mass and spin is a suitable gauge group for gravity. A Yang-Mills spin 2 gauge theory of gravity is proposed.

Higgs gravitational vacuum in the gauge gravitation theory

The Higgs-Goldstone nature of a gravitational field responsible for spontaneous breaking of space-time symmetries is examined. The Higgs matter vacuum is suggested to be the source of the Higgs gravitational vacuum.

The metric and the canonical energy-momentum currents in the poincaré gauge theory of gravitation

The relation between the metric (“Hilbert”) and the canonical (“Noether”) energy-momentum currents is derived in a natural way in the context of the variational formalism of the Poincaré gauge theory.

Gauge Theory of Gravitation: A Unified Formulation of Poincare and (Anti-)De Sitter Gauge Theories

Gauge Theory of Gravitation: A Unified Formulation of Poincare and (Anti-)De Sitter Gauge Theories

DIFFEOMORPHICALLY NONEQUIVALENT CLASSES OF SOLUTIONS IN GAUGE THEORIES ON GROUP MANIFOLDS

For the Poincare group manifold we prove that there are solutions for the pseudo-connection one-forms (Yang-Mills potentials) which are not diffeomorphically equivalent to those initially proposed by Ne’eman and Regge in their gauge theory of gravity and supergravity on a (super) group manifold. This is done by imposing the factorization conditions to the geometrical formulation of supersymmetric gauge theory.

Dynamical cosmic strings from a gauge theory of gravity.

A new dynamical realization of O(5) gauge Euclidean gravity is proposed and shown to possess topologically nontrivial features, cosmic-string flux tubes and dark-matter solitons, of a purely gravitational origin (no Higgs particle needed).

Cylindrically symmetric solutions of self-consistently coupled Dirac fields in gauge theories of gravity

In the framework of the Einstein-Cartan theory (ECT) with a Dirac field as source, the authors find an exact cylindrically symmetric solution, where the Dirac field has to fulfil certain algebraic constraints. Moreover, turning to the Poincare gauge theory (PGT), with a Lagrangian which is at most quadratic in torsion and curvature, they find a related exact solution. The tetrad and the spinor fields are the same as in the Einstein-Cartan case and the torsion is also proportional to the spin current.

Gravitation and the gauge theory of dislocations

The gauge theory of gravitation has long been dominated by the model of a gravitational field as a gauge field of the translation group. However, a fiber bundle analysis showed that one cannot identify these two fields. This led to the question concerning the physical meaning of the gauge fields of the translation group. The answer to this question can be given from the point of view of the gauge theory of dislocations. The argument stresses the special character of the gauge field of the translation group, not related to the Einstein gravity, and the incorrectness of the wide-spread attempts to represent gravity as a kind of space-time deformation.

A remark on the axisymmetric Chen et al. solution of the Poincaré gauge theory

Recently the search for exact solutions of the Poincaré gauge theory of gravity was highlighted by the independent discovery of two Kerr-type solutions with dynamic torsion. Some properties of these axisymmetric solutions, found by Chen et al. and by McCrea et al., are compared and put into proper perspective. In particular we show that the Chen et al., solution, in marked contrast to the more general McCrea et al. solution, belongs to a class of quadratic Poincaé gauge lagrangians of a highly degenerate nature, which admits non-unique solutions already in the limit of spherical symmetry.

Hamiltonian Structure of Poincaré Gauge Theory and Separation of Non-Dynamical Variables in Exact Torsion Solutions

The canonical Hamiltonian of the Poincaré gauge theory of gravity is reanalyzed for generic Lagrangians. It is shown that the time components e0α and Γ0αβ of the tetrad and the linear connection fields of a Riemann-Cartan space-time U4 constitute gauge degrees of freedom which remain non-dynamical during the time evolution of the system. Whereas the e0α are to be identified with the lapse and shift functions Nα known from the ADM formalism in Einstein's theory, the additional Lorentz degrces of freedom Γ0αβ are pertinent to Poincaré gauge models. These non-dynamical variables are instrumental in the derivation of exact torsion solutions obeying modified double duality conditions for the U4-curvature. Thereby, in the case of spherical symmetry and for the charged Taub-NUT metric, we obtain the most general torsion configuration for a large class of quadratic Lagrangians. Previously found solutions are contained therein and can be recovered after fixing special “gauge”.

Kaluza-Klein theory from the viewpoint of gauge theory of gravity

We consider Kaluza-Klein theory based on the fiber bundle. We obtain the modified Kaluza-Klein metric as an invariant line element of a bundle. Its reduced action includes a higher derivative action in gravitation as well as a term linear inR.

Diffeomorphically nonequivalent classes of solutions in gauge theories on group manifolds

For the Poincare group manifold we prove that there are solutions for the pseudoconnection one-forms (Yang-Mills potentials) which are not diffeomorphically equivalent to those initially proposed by Ne'eman and Regge in their gauge theory of gravity and supergravity on a (super) group manifold. This is done by imposing the factorization conditions on the geometrical formulation of supersymmetric gauge theory.

Anti-Higgs effect in two-dimensional gauge theories

Two-dimensional gravitational and vector gauge theories obtained by reduction of D=3 topologically massive ones exhibit an 'anti-Higgs' effect: the gauge fields are absorbed by their massless scalar or spinor partners which thereby acquire a mass. The analysis of the supersymmetric vector model is also carried out in superspace, where it is shown that it can be correspondingly formulated in terms of pseudoscalar (rather than spinor) superfield strengths. Its first-order formulation is used to derive the self-interaction by a Noether procedure from the Abelian action, directly in superspace. The scalar superfield is also used to construct other sigma -model-like non-linear actions.