The isotropy of the universe.
Einstein equations with flat homogeneous hypersurfaces including effects of viscosity in radiation and anisotropic pressures
Misner, C. W.↗
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Klein-Gordon geon.
Spherically symmetric eigenstates of Klein- Gordon Einstein equations, discussing gravitational collapse
Kaup, D. J.↗
Outline of relativistic cosmology for cosmic gamma-ray studies
Einstein equation using differential geometry to identify gravitational fields
Stecker, F. W.↗
A singularity-free empty universe.
Einstein equations solution for empty space without singularities containing metric, with closed homogeneous space type hypersurfaces expanding anisotropically
Misner, C. W.↗
Degenerate gravitational fields with twisting rays.
Einstein equations for empty space applied to degenerate gravitational fields with twisting rays, admitting shear-free twisting congruence of null geodesics
Robinson, I.↗
Quantum cosmology. I
Hamiltonian methods applied to homogeneous cosmological models, obtaining Einstein equations, passing to quantum theory by imposing canonical commutation relations
Misner, C. W.↗
Classical and quantum dynamics of a closed universe
Closed universe classical and quantum dynamics by ADM Hamiltonian treatment of Einstein equations for homogeneous cosmological models
Misner, C. W.↗
Dust-filled universes of Class II and Class III
Physical and geometrical properties of dust filled universes, using left invariant metrics compatible with Einstein equations
Ozsvath, I.↗
Quantum graviton creation in a model universe
Consideration of the mechanism of production of gravitons in the empty, anisotropic, spatially inhomogeneous Gowdy three-torus cosmology. The Gowdy cosmology is an exact solution of the vacuum Einstein equations and is obtained as a generalization of the homogeneous empty Bianchi Type I (Kasner) cosmology by permitting the metric components to depend on one of the space variables in addition to time. The Hamiltonian methods of Arnowitt, Deser, and Misner are employed to identify the dynamical variables which are to be quantized. The WKB regime solution is identical to that found by Doroshkevich, Zel'dovich, and Novikov (DZN) for a universe containing collisionless anisotropic radiation. Using a procedure similar to that of Parker (1971) or Zel'dovich and Starobinskii (1971) for defining quantum number, it is found that the DZN large-time radiation consists of quanta (gravitons) created from an initial vacuum. The quantum behavior is much like the semiclassical enhancement of quantum number with the added feature of creation of quanta from vacuum fluctuations.
Berger, B. K.↗
Analytic pulsar models
An analytical procedure is given for solving the Einstein equations of a rotating fluid body. It is demonstrated that an analytic model of uniform denisty, representing a slowly rotating neutron star, can describe both differentially and uniformly rotating stars.
Adams, R. C.↗
Quantum descriptions of singularities leading to pair creation
A class of cosmological models is analyzed which provide a mathematically convenient (but idealized) description of a cosmological singularity that develops into a pair creation epoch and terminates in an adiabatic expansion with redshifting particle energies. This class of models was obtained by Gowdy (1971, 1974) as a set of exact solutions of the classical empty space Einstein equations describing inhomogeneous universes populated only by gravitational waves. It is shown that these models can be used to exhibit simplified models of quantized gravitational fields, and that a quantum description can be given arbitrarily near a cosmological singularity. Graviton pair creation occurs, and can be seen to convert anisotropic expansion rates into the energy of graviton pairs.
Misner, C. W.↗
Scale-covariant theory of gravitation and astrophysical applications
Generalized Einstein equations invariant under scale transformations are presented, and several astrophysical tests studied. It is assumed that the dynamics of atoms or clocks used as measuring apparatus is given a priori. Connection with gauge fields and broken symmetries is made through the cosmological constant.
Canuto, V.↗
Determination of the zincate diffusion coefficient and its application to alkaline battery problems
The diffusion coefficient for the zincate ion at 24 C was found to be 9.9 X 10 to the minus 7th power squared cm per sec + or - 30 percent in 45 percent potassium hydroxide and 1.4 x 10 to the minus 7 squared cm per sec + or - 25 percent in 40 percent sodium hydroxide. Comparison of these values with literature values at different potassium hydroxide concentrations show that the Stokes-Einstein equation is obeyed. The diffusion coefficient is characteristic of the zincate ion (not the cation) and independent of its concentration. Calculations with the measured value of the diffusion coefficient show that the zinc concentration in an alkaline zincate half cell becomes uniform throughout in tens of hours by diffusion alone. Diffusion equations are derived which are applicable to finite size chambers. Details and discussion of the experimental method are also given.
May, C. E.↗
Determination of the zincate diffusion coefficient and its application to alkaline battery problems
The diffusion coefficient for the zincate ion at 24 C was found to be 9.9 x 10 to the -7th power sq cm/sec + or - 30% in 45% potassium hydroxide and 1.4 x 10 to the -7th power sq cm/sec + or - 25% in 40% sodium hydroxide. Comparison of these values with literature values at different potassium hydroxide concentrations show that the Stokes-Einstein equation is obeyed. The diffusion coefficient is characteristic of the zincate ion (not the cation) and independent of its concentration. Calculations with the measured value of the diffusion coefficient show that the zinc concentration in an alkaline zincate half-cell becomes uniform throughout in tens of hours by diffusion alone. Diffusion equations are derived which are applicable to finite-size chambers. Details and discussion of the experimental method are also given.
May, C. E.↗
The origins of cosmic rays and quantum effects on gravity
The energy spectrum of primary cosmic rays is explained by particles emitted during a thermal expansion of explosive objects inside and near the galaxy, remnants of which may be supernova and/or active talaxies, or even stars or galaxies that disappeared from our sight after the explosion. A power law energy spectrum for cosmic rays, E to the (-alpha -1, is obtained from an expansion rate T is proportional to R to the alpha. Using the solution of the Einstein equation, we obtain a spectrum which agrees very well with experimental data. The implication of an inflationary early universe on the cosmic ray spectrum is also discussed. It is also suggested that the conflict between this model and the singularity theorem in classical general relativity may be eliminated by quantum effects.
Tomozawa, Y.↗
Non-existence of dynamical perturbations of Schwarzschild with vanishing self-dual part
A recent proposal of Ashtekar (1985) for the canonical quantisation of gravity involves a new choice of a (complex) polarisation on the (real) phase space of general relativity. In order for the 'four dimensional' version of Ashtekar's proposal to be viable, it is necessary that for an arbitrary (real) background solution there exist a sufficient number of (complex) solutions of the linearised Einstein equation with perturbed Weyl spinor having vanishing self-dual part. It is shown that this is not the case by explicitly demonstrating that for the Schwarzschild spacetime, aside from stationary perturbations, there are no such linearised solutions which can be expressed as superpositions of modes of real frequencies. The viability of the '3+1 version' of Ashtekar's proposal is not affected by these considerations.
Wald, R. M.↗
An exact solution for a thick domain wall in general relativity
An exact solution of the Einstein equations for a static, planar domain wall with finite thickness is presented. At infinity, density and pressure vanish and the space-time tends to the Minkowski vacuum on one side of the wall and to the Taub vacuum on the other side. A surprising feature of this solution is that the density and pressure distribution are symmetric about the central plane of the wall whereas the space-time metric and therefore also the gravitational field experienced by a test particle is asymmetric.
Goetz, Guenter↗
Conformal scalar field wormholes
The Euclidian Einstein equations with a cosmological constant and a conformally coupled scalar field are solved, taking the metric to be of the Robertson-Walker type. In the case Lambda = 0, solutions are found which represent a wormhole connecting two asymptotically flat Euclidian regions. In the case Lambda greater than 0, the solutions represent tunneling from a small Tolman-like universe to a large Robertson-Walker universe.
Halliwell, Jonathan J.↗