No Arabic abstract
We show that if we start with the free Dirac Lagrangian, and demand local phase invariance, assuming the total phase coming from two independent contributions associated with the charge and mass degrees of freedom of charged Dirac particles, then we are forced to introduce two massless independent vector fields for charged Dirac particles that generate all of electrodynamics and gravitodynamics of Heavisides Gravity of 1893 or Maxwellian Gravity and specify the charge and mass currents produced by charged Dirac particles. From this approach we found: (1) a new set of Maxwell-Lorentz equations, (2) two equivalent sets of gravito-Maxwell-Lorentz equations (3) a gravitational correction to the standard Lagrangian of electrodynamics, which, for a neutral massive Dirac particle, reduces to the Lagrangian for gravitodynamics, (4) attractive interaction between two static like masses, contrary to the prevalent view of many field theorists and (5) gravitational waves emanating from the collapsing process of self gravitating systems carry positive energy and momentum in the spirit of Maxwells electromagnetic theory despite the fact that the intrinsic energy of static gravitoelectromagnetic fields is negative as dictated by Newtons gravitational law and its time-dependent extensions to Heaviside-Maxwellian Gravity (HMG). Fundamental conceptual issues in linearized Einsteins Gravity are also discussed.
The metric of a homogenously accelerated system found by Harry Lass is a solution of the Einstein s equation. The metric of an isotropic homogenous field must satisfy the new gravitational equation.
We bootstrap loop corrections to AdS${}_5$ supergravity amplitudes by enforcing the consistency of the known classical results with the operator product expansion of $mathcal{N}=4$ super Yang-Mills theory. In particular this yields much new information on the spectrum of double-trace operators which can then be used, in combination with superconformal symmetry and crossing symmetry, to obtain a prediction for the one-loop amplitude for four graviton multiplets in AdS. This in turn yields further new results on subleading $O(1/N^4)$ corrections to certain double-trace anomalous dimensions.
This article presents an extended model of gravity obtained by gauging the AdS-Mawell algebra. It involves additional fields that shift the spin connection, leading effectively to theory of two independent connections. Extension of algebraic structure by another tetrad gives rise to the model described by a pair of Einstein equations.
Renormalization group methods are applied to a scalar field within a finite, nonlocal quantum field theory formulated perturbatively in Euclidean momentum space. It is demonstrated that the triviality problem in scalar field theory, the Higgs boson mass hierarchy problem and the stability of the vacuum do not arise as issues in the theory. The scalar Higgs field has no Landau pole.
We deal with quadratic metric-affine gravity (QMAG), which is an alternative theory of gravity and present a new explicit representation of the field equations of this theory. In our previous work we found new explicit vacuum solutions of QMAG, namely generalised pp-waves of parallel Ricci curvature with purely tensor torsion. Here we do not make any assumptions on the properties of torsion and write down our field equations accordingly. We present a review of research done thus far by several authors in finding new solutions of QMAG and different approaches in generalising pp-waves. We present two conjectures on the new types of solutions of QMAG which the ansatz presented in this paper will hopefully enable us to prove.