George Chapline

Unification of Yang-Mills Theory and Supergravity in Ten-Dimensions

We show how to generalize the coupling of n=1 super-Maxwell theory and n=1 supergravity in 10-dimensions to the case of a non-abelian gauge group. We find that the supergravity 2-form potential a/sub ..mu nu../ is coupled to the Yang-Mills gauge potential A/sub ..mu../ via the Chern-Simons 3-form.

Dimensional reduction and flavor chirality

We show that phenomenologically realistic flavor-chiral Yang-Mills-Higgs theories in 4 dimensions can be derived by dimensional reduction of 10-dimensional vectorlike and gauge theories, where the extra 6 dimensions form a compact coset space with scale size r. The dimensional reduction often implies a symmetry breaking pattern like that of the electroweak theory, in which case it is natural to propose r ⋍ GF12. Quantum effects then determine the short-distance behavior of the theory, including any additional symmetry breaking.

The geometrical significance of certain Higgs potentials: An approach to grand unification

Abstract It is pointed out that the Higgs potentials in certain Yang-Mills-Higgs theories are natural, in the sense that they can be derived by dimensionally reducing pure Yang-Mills theories defined in more than four space-time dimensions. In particular, when the symmetry group of the space of extra dimensions is a subgroup of the initial gauge group, then the Higgs potential can be given a purely group-theoretic interpretation. An interesting class of grand-unified-like models with Higgs potentials of this type can be derived using the exceptional group E8 as initial gauge group. One property of these models is that they are characterized by very few arbitrary parameters; nevertheless, a hierarchy of gauge symmetry breaking is still possible.

Calculation of gain at X-ray wavelengths resulting from optical pumping of helium-like ions

Abstract An equivalent two level scheme is described for calculating level populations of helium-like ions in dense optically thick plasmas. The scheme is used to show how population inversions due to optical pumping of 3Por 4P states are affected by line trapping. The importance of various line broadening mechanisms for determining gain is briefly discussed.

Tommy Gold Revisited: Why Doesn’t the Universe Rotate?

Understanding gravitational collapse requires understanding how ∼1058 nucleons can be destroyed in ∼10−5 seconds. The recent proposal that the endpoint of gravitational collapse can be a “dark energy star” implies that the mass‐energy of the nucleons undergoing gravitational collapse can be converted to vacuum energy when one gets near to conditions where classical general relativity predicts that a trapped surface would form. The negative pressure associated with a large vacuum energy prevents an event horizon from forming, thus resolving the long‐standing puzzle as to why gravitational collapse always leads to an explosion. An indirect consequence is that the reverse process — creation of matter from vacuum energy — should also be possible. Indeed this process may be responsible for the “big bang”. In this new cosmology the observable universe began as a fluctuation in an overall steady state universe. The fluctuations in the CMB in this picture are the result of quantum turbulence associated with vorti...

Unification of elementary particle physics and cosmology in ten dimensions

Abstract Ten-dimensional cosmological solutions of the coupled supergravity-Yang-Mills equations are described for which spacetime at late times has the form M 4 × J / R , where M 4 is a Friedman-like four-dimensional universe and J / R is a compact coset space with constant scale parameter. In these models Newtons constant, the W-mass, and the fine structure constant do not vary appreciably with time during observable epochs.

X-Ray Biomicroholography

We discuss alternative techniques for microholography of biological specimens including requirements and constraints on the optical elements and recording media. We derive spatial and temporal coherence requirements for four representative holographic techniques and relate coherence and recording-medium resolution to maximum specimen volume. We give estimates of coherence length necessary to image a variety of specimens under a realistic set of assumptions. We discuss matters of wavelength selection with emphasis on the problem of obtaining high contrasts for nitrogen-bearing biological constituents. We use the eikonal approximation to derive equations for diffractive holographic imaging with particular attention to specimens of low contrast, and use these to illustrate the benefits of using 27r9 resonances to image molecular structures.

Dimension reduction and massless chiral fermions

Abstract Dimensional reduction of a Yang-Mills theory, when the space of extra dimensions is a compact homogeneous space, can lead to families of flavor chiral fermions. Using the Atiyah-Singer theorem we show that when representation mixing is neglected, some of these families can be massless even in the presence of a non-vanishing I = 1 2 Higgs field.

Conformal field theory and a topological quantum theory of vortices and knots

Abstract We examine the two-dimensional quantum field theory with topological action rmTr ∫ d 2 xϵ ij ( 1 4 F ij [Φ ∗ ,Φ] − D i Φ ∗ D j Φ) . In the semi-classical limit the action will be dominated by self-dual vortices associated with singularities in the reduction of a four-dimensional topological theory to a Riemann surface. We propose that the creation operators for these vortices can be identified with the primary fields of a current algebra, and this leads to fractional statistics for the vortices. Expressing the Berry phase associated with unwinding a knot in terms of the phase for exchanging two vortices then provides a link between conformal field theory and the Donaldson theory of four-manifolds. If self-duality is imposed as a gauge condition, the low-temperature limit of the theory resembles the world-sheet action for a superstring.

Fission fragment rocket concept

Abstract A new propulsion scheme is outlined which may permit interstellar missions for spacecraft. This scheme is based on the idea of allowing fission fragments to escape from the core of a nuclear reactor.