Weyl gravity as general relativity

When the full connection of Weyl conformal gravity is varied instead of just the metric, the resulting vacuum field equations reduce to the vacuum Einstein equation, up to the choice of local units, if and only if the torsion vanishes. This result differs strongly from the usual fourth-order formulation of Weyl gravity.Comment: Final version, 11 pages. The role of torsion is clarified, two appendices - on structure equations and Bianchi identities and on the basis equation - have been adde

Extended Conformal Symmetry

We show that the grading of fields by conformal weight, when built into the initial group symmetry, provides a discrete, non-central conformal extension of any group containing dilatations. We find a faithful vector representation of the extended conformal group and show that it has a scale-invariant scalar product and satisfies a closed commutator algebra. The commutator algebra contains the infinite Heisenberg and Virasoro algebras. In contrast to the classical treatment of scale invariance, covariant derivatives and gauge transformations automatically incorporate the correct conformal weights when the extended symmetry is gauged.Comment: 15 page

Normal Biconformal Spaces

A new 8-dimensional conformal gauging avoids the unphysical size change, third order gravitational field equations, and auxiliary fields that prevent taking the conformal group as a fundamental symmetry. We give the structure equations, gauge transformations and intrinsic metric structure for the new biconformal spaces. We prove that a torsion-free biconformal space with exact Weyl form, closed dilational curvature and trace-free spacetime curvature admits a sub-bundle of vanishing Weyl form homeomorphic to the Whitney sum bundle of the tangent bundle and the bundle of orthonormal Lorentz frames over 4-dimensional spacetime. Conversely, any 4-dimensional spacetime extends uniquely to such a normal biconformal space. The Einstein equation holds if and only if the biconformal basis is orthonormal. Unconstrained antisymmetric trace of the spacetime curvature provides a closed 2-form, independent of the Weyl vector, consistently interpretable as the electromagnetic field. The trace of the spacetime co-torsion decouples from gravitational sources and serves as electromagnetic source.Comment: 32 pages, plain TeX, no figure

Quanta Without Quantization

The dimensional properties of fields in classical general relativity lead to a tangent tower structure which gives rise directly to quantum mechanical and quantum field theory structures without quantization. We derive all of the fundamental elements of quantum mechanics from the tangent tower structure, including fundamental commutation relations, a Hilbert space of pure and mixed states, measurable expectation values, Schroedinger time evolution, collapse of a state and the probability interpretation. The most central elements of string theory also follow, including an operator valued mode expansion like that in string theory as well as the Virasoro algebra with central charges.Comment: 8 pages, Latex, Honorable Mention 1997 GRG Essa

Actions for Biconformal Matter

We extend 2n-dim biconformal gauge theory by including Lorentz-scalar matter fields of arbitrary conformal weight. For a massless scalar field of conformal weight zero in a torsion-free biconformal geometry, the solution is determined by the Einstein equation on an n-dim submanifold, with the stress-energy tensor of the scalar field as source. The matter field satisfies the n-dim Klein-Gordon equation.Comment: 5 page

Time and dark matter from the conformal symmetries of Euclidean space

The quotient of the conformal group of Euclidean 4-space by its Weyl subgroup results in a geometry possessing many of the properties of relativistic phase space, including both a natural symplectic form and non-degenerate Killing metric. We show that the general solution posesses orthogonal Lagrangian submanifolds, with the induced metric and the spin connection on the submanifolds necessarily Lorentzian, despite the Euclidean starting pont. By examining the structure equations of the biconformal space in an orthonormal frame adapted to its phase space properties, we also find that two new tensor fields exist in this geometry, not present in Riemannian geometry. The first is a combination of the Weyl vector with the scale factor on the metric, and determines the timelike directions on the submanifolds. The second comes from the components of the spin connection, symmetric with respect to the new metric. Though this field comes from the spin connection it transforms homogeneously. Finally, we show that in the absence of conformal curvature or sources, the configuration space has geometric terms equivalent to a perfect fluid and a cosmological constant.Comment: 26 pages, no figures. Appreciable introductory material added. Results substantially strengthened and explained. New results concerning dark matter and dark energy candidates added to this versio