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161.
J. Towe 《International Journal of Theoretical Physics》2008,47(11):2898-2903
It is demonstrated that gauge invariant states within local super-symmetry are equivalent to quantized states of global super-symmetry
that are preserved by (oblivious to) super-gravitational interactions (analogous to the stationary atomic states that derive
from gauge invariance in the theory of Weyl). The cosmology which emerges from this equivalence is unique and finite, and
parallels observation. Specifically, mass-energy distributions occur about intersections of phase transitions that modify
the shock front of global expansion, and the predicted number of galaxies approximates that determined by observation. 相似文献
162.
Given the particle content of the standard model without and with a right-handed neutrino, the requirement that all anomalies
cancel singles out a set of possible global symmetries which can be gauged. I review this topic and propose a new gauge symmetryB — 3L
T in the context of the minimal standard model consisting of the usual three families of quarks and leptons plus just onev
R. The many interesting phenomenological consequences of this hypothesis are briefly discussed. 相似文献
163.
Mean-field treatments of Yang-Mills theory face the problem of how to treat the Gauss law constraint. In this paper we try to face this problem by studying the excited states instead of the ground state. For this purpose we extend the operator approach to the Random Phase Approximation (RPA) well-known from nuclear physics and recently also employed in pion physics to general bosonic theories with a standard kinetic term. We focus especially on conservation laws, and how they are translated from the full to the approximated theories, demonstrate that the operator approach has the same spectrum as the RPA derived from the time-dependent variational principle, and give—for Yang-Mills theory—a discussion of the moment of inertia connected to the energy contribution of the zero modes to the RPA ground state energy. We also indicate a line of thought that might be useful to improve the results of the Random Phase Approximation. 相似文献
164.
A perturbative SU(3) Casson invariant for integral homology 3-sphere is defined. Besides being fully perturbative, it has the nice properties: (1) is an integer. (2) It is preserved under orientation change. (3) A connect sum formula. Explicit calculations of the invariant
for 1/k surgery of (2, q) torus knot are presented and compared with Boden-Herald‚s different SU(3) generalization of Casson‚s invariant. For those cases computed, the invariant defined here is a quadratic polynomial in
k for k > 0 and a different quadratic polynomial for k < 0.
Received: October 12, 2000 相似文献
165.
L. L. Salcedo 《Physics letters. [Part B]》2002,530(1-4):244-250
It is argued that the derivative expansion is a suitable method to deal with finite temperature field theory, if it is restricted to spatial derivatives only. Using this method, a simple and direct calculation is presented for the radiatively induced Chern–Simons-like piece of the effective action of (2+1)-dimensional fermions at finite temperature coupled to external gauge fields. The gauge fields are not assumed to be subjected to special constraints, and in particular, they are not required to be stationary nor Abelian. 相似文献
166.
This is the second of a couple of papers in which we aim to show the peculiar capability of the Hamiltonian ADM formulation
of metric gravity to grasp a series of conceptual and technical problems that appear to have not been directly discussed so
far. In this paper we also propose new viewpoints about issues that, being deeply rooted into the foundational level of Einstein
theory, seem particularly worth of clarification in connection with the alternative programs of string theory and loop quantum
gravity. The achievements of the present work include: (1) the analysis of the so-called Hole phenomenology in strict connection with the Hamiltonian treatment of the initial value problem. The work is carried through
in metric gravity for the class of spatially non-compact Christoudoulou-Klainermann space-times, in which the temporal evolution
is ruled by the weak ADM energy. It is crucial to our analysis the re-interpretation of active diffeomorphisms as passive and metric-dependent dynamical symmetries of Einstein's equations, a re-interpretation which enables to disclose their (nearly unknown) connection
to gauge transformations on-shell; this is expounded in the first paper (gr-qc/0403081); (2) the utilization of the Bergmann-Komar
intrinsic pseudo-coordinates, defined as suitable functionals of the Weyl curvature scalars, as tools for a specific gauge-fixing to the super-hamiltonian
and super-momentum constraints; (3) the consequent construction of a physical atlas of 4-coordinate systems for the 4-dimensional mathematical manifold, in terms of the highly non-local degrees of freedom of the gravitational field (its four independent Dirac observables). Such construction embodies the physical individuation of the points of space-time as point-events, both in absence and presence of matter, and associates a non-commutative structure to each gauge fixing or 4-dimensional coordinate system; (4) a clarification of the multiple definition given by Peter Bergmann
of the concept of (Bergmann) observable in general relativity. This clarification leads to the proposal of a main conjecture asserting the existence of: i) special Dirac's observables which are also Bergmann's observables, ii) gauge variables that
are coordinate independent (namely they behave like the tetradic scalar fields of the Newman-Penrose formalism). A by-product
of this achievements is the falsification of a recently advanced argument asserting the absence of (any kind of) change in the observable quantities of general relativity; (5) a proposal showing how the physical individuation of point-events
could in principle be implemented as an experimental setup and protocol leading to a standard of space-time more or less like atomic clocks define standards of time.
In the end, against the well-known Einstein's assertion according to which general covariance takes away from space and time the last remnant of physical objectivity, we conclude that point-events maintain a peculiar sort of objectivity. Also, besides being operationally essential for building measuring apparatuses for the gravitational field, the role of
matter in the non-vacuum gravitational case is also that of participating directly in the individuation process, being involved in the determination of the Dirac observables. Finally, some hints following
from our approach for the quantum gravity programme are suggested. 相似文献
167.
In this review we present the salient features of dynamical chaos in classical gauge theories with spatially homogeneous fields.
The chaotic behaviour displayed by both abelian and non-abelian gauge theories and the effect of the Higgs term in both cases
are discussed. The role of the Chern-Simons term in these theories is examined in detail. Whereas, in the abelian case, the
pure Chern-Simons-Higgs system is integrable, addition of the Maxwell term renders the system chaotic. In contrast, the non-abelian
Chern-Simons-Higgs system is chaotic both in the presence and the absence of the Yang-Mills term. We support our conclusions
with numerical studies on plots of phase trajectories and Lyapunov exponents. Analytical tests of integrability such as the
Painlevé criterion are carried out for these theories. The role of the various terms in the Hamiltonians for the abelian Higgs,
Yang-Mills-Higgs and Yang-Mills-Chern-Simons-Higgs systems with spatially homogeneous fields, in determining the nature of
order-disorder transitions is highlighted, and the effects are shown to be counter-intuitive in the last-named system. 相似文献
168.
Tomasz Brzeziński 《Journal of Geometry and Physics》1996,20(4):349-370
The notion of a translation map in a quantum principal bundle is introduced. A translation map is then used to prove that the cross sections of a quantum fibre bundle E((B, V, A) associated to a quantum principal bundle P (B, A) are in bijective correspondence with equivariant maps V → P, and that a quantum principal bundle is trivial if it admits a cross section which is an algebra map. The vertical automorphisms and gauge transformations of a quantum principal bundle are discussed. In particular it is shown that vertical automorphisms are in bijective correspondence with AdR-covariant maps A → P. 相似文献
169.
Junpei Harada 《Fortschritte der Physik》2016,64(6-7):510-515
Gauge coupling unification is studied within the framework where there are extra Higgs doublets and E6 exotic fields. Supersymmetric models and nonsupersymmetric models are investigated, and a catalog of models with gauge coupling unification is presented. 相似文献
170.
We consider effective actions of the cosmological Friedmann–Robertson–Walker (FRW) models and discuss their fermionic rigid BRST invariance. Further, we demonstrate the finite field-dependent BRST transformations as a limiting case of continuous field-dependent BRST transformations described in terms of continuous parameter κ. The Jacobian under such finite field-dependent BRST transformations is computed explicitly, which amounts an extra piece in the effective action within functional integral. We show that for a particular choice of a parameter the finite field-dependent BRST transformation maps the generating functional for FRW models from one gauge to another. 相似文献