Gravitational Scalar Field Research Articles

Gravitational Field in the Unified Spinor Field Theory

The possible existence of the gravitational field within the framework of the unified spinor field theory is examined. Though the nonlinear term in the theory might be mainly responsible for hadronic processes, it could also be a source for the realization of the gravi· tational field as well as the electromagnetic field. A conjecture is made for the introduction of the neutrino with nonzero mass as a clue to the gravitational field just as the charged lepton is to the electromagnetic field. A series of crossed ladder diagrams is taken for the scattering amplitude between baryons to have a coupling constant given by the residue of a spin 2 pole with zero mass. An estimate with a special approximation gives GM2;;;:;.2TC(v/M) for the empirical value 5.9·10·89, where M and v denote the baryon and the neutrino mass respectively. Our result gives GM 2;;;:;.0.6·10-89 near the upper bound of the empirical.mass of the beta-neutrino, 200 eV. The existence of a scalar gravitational field with small mass is not allowed in our considerations.

Geometrization of the Brans-Dicke Scalar Field

The Brans-Dicke gravitational scalar field is geometrized in the spirit of the Rainich-Misner-Wheeler geometrization of electromagnetism. Geometric equations are derived which imply that the Brans-Dicke field is present and an explicit expression is given for this field in terms of geometrical quantities.

Axially Symmetric Zero-Mass Meson Solutions of Einstein Equations

The field equations for the coupled zero-mass scalar field and gravitational fields are solved in the axially symmetric static case. It is found that the scalar field obeys a flat-space Laplace's equation such that a large class of solutions exists. The spherically symmetric limiting solution is shown to be a simplified version of the solution due to Jains et al.

Scalar Gravitational Fields in Pulsating Stars

Brans and Dicke have suggested the existence of a scalar field in their theory of gravitation. The role of a scalar gravitational field in pulsating stars is studied. It is found that a star in a radially symmetric pulsational motion can radiate scalar waves but not gravitational waves. Further, radiation of scalar waves can damp out the radial pulsation of a neutron star in a matter of seconds. Thus, if a neutron star is found to pulsate, then the existence of a scalar field can be ruled out.

Effect of Gravitational Scalar Field on High-Density Star Structure

The theory of gravitation allowing variation of the gravitational constant $G$ by means of a scalar field introduced by Brans and Dicke is applied in the case of a fluid sphere in gravitational equilibrium. The departure of the mass-radius relation in this theory from the Einstein theory is investigated for different values of the constant $\ensuremath{\omega}$ and for high central-energy densities in completely degenerate stars (neutron stars).

A gravimeter to monitor the0S0dilational mode of the Earth

A gravimeter designed specifically to monitor the 0S0 dilational mode of the earth is described. The gravimeter is a modified LaCoste design constructed of fused quartz, operated in a high vacuum, and incorporated into an electrostatic null-seeking servo. The gravimeter data are digitally Fourier analyzed after passage through a heterodyne tide filter. The observed spectral density of the noise at 20-minute periods is 10−7 g/cpm. The noise can be attributed to temperature and tilt fluctuations and is not actual vertical earth noise. The purpose of the experiment is to search for evidence of scalar gravitational field radiation which may drive the 0S0 mode.

Construction of Combined Scalar-Gravitational Fields from Purely Gravitational Case

Construction of Combined Scalar-Gravitational Fields from Purely Gravitational Case

The Eötvös experiment, spatial isotropy, and generally covariant field theories of gravity

It has been suggested that the numerical value of the fine structure “constant” may in fact be variable, being determined by the distribution of matter in the universe. However, there is some reason to believe that this conjecture is not consistent with the observed structure independence of gravitationa acceleration and the test of spatial isotropy discussed by Drever and others. The purpose of this article is to discuss this idea within the framework of a classical, generally covariant field theory. The usual electromagnetic field equations are modified so that the value of the fine structure constant which one would determine from a local experiment is given by a scalar gravitational field. With these modified equations, a field theory of gravity in which the motion of free test particles is consistent with the observed structure independence of gravitational acceleration may be constructed in a straightforward way. However, it is shown that this theory must be ruled out by the experimental observations of spatial isotropy.