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Recent Results Regarding Affine Quantum Gravity
Recent progress in the quantization of nonrenormalizable scalar fields has
found that a suitable non-classical modification of the ground state wave
function leads to a result that eliminates term-by-term divergences that arise
in a conventional perturbation analysis. After a brief review of both the
scalar field story and the affine quantum gravity program, examination of the
procedures used in the latter surprisingly shows an analogous formulation which
already implies that affine quantum gravity is not plagued by divergences that
arise in a standard perturbation study. Additionally, guided by the projection
operator method to deal with quantum constraints, trial reproducing kernels are
introduced that satisfy the diffeomorphism constraints. Furthermore, it is
argued that the trial reproducing kernels for the diffeomorphism constraints
may also satisfy the Hamiltonian constraint as well.Comment: 32 pages, new features in this alternative approach to quantize
gravity, minor typos plus an improved argument in Sec. 9 suggested by Karel
Kucha
Krein's spectral theory and the Paley-Wiener expansion for fractional Brownian motion
In this paper we develop the spectral theory of the fractional Brownian
motion (fBm) using the ideas of Krein's work on continuous analogous of
orthogonal polynomials on the unit circle. We exhibit the functions which are
orthogonal with respect to the spectral measure of the fBm and obtain an
explicit reproducing kernel in the frequency domain. We use these results to
derive an extension of the classical Paley-Wiener expansion of the ordinary
Brownian motion to the fractional case.Comment: Published at http://dx.doi.org/10.1214/009117904000000955 in the
Annals of Probability (http://www.imstat.org/aop/) by the Institute of
Mathematical Statistics (http://www.imstat.org
Noncanonical Quantization of Gravity. I. Foundations of Affine Quantum Gravity
The nature of the classical canonical phase-space variables for gravity
suggests that the associated quantum field operators should obey affine
commutation relations rather than canonical commutation relations. Prior to the
introduction of constraints, a primary kinematical representation is derived in
the form of a reproducing kernel and its associated reproducing kernel Hilbert
space. Constraints are introduced following the projection operator method
which involves no gauge fixing, no complicated moduli space, nor any auxiliary
fields. The result, which is only qualitatively sketched in the present paper,
involves another reproducing kernel with which inner products are defined for
the physical Hilbert space and which is obtained through a reduction of the
original reproducing kernel. Several of the steps involved in this general
analysis are illustrated by means of analogous steps applied to one-dimensional
quantum mechanical models. These toy models help in motivating and
understanding the analysis in the case of gravity.Comment: minor changes, LaTeX, 37 pages, no figure
Quantum mechanics of null polygonal Wilson loops
Scattering amplitudes in maximally supersymmetric gauge theory are dual to
super-Wilson loops on null polygonal contours. The operator product expansion
for the latter revealed that their dynamics is governed by the evolution of
multiparticle GKP excitations. They were shown to emerge from the spectral
problem of an underlying open spin chain. In this work we solve this model with
the help of the Baxter Q-operator and Sklyanin's Separation of Variables
methods. We provide an explicit construction for eigenfunctions and eigenvalues
of GKP excitations. We demonstrate how the former define the so-called
multiparticle hexagon transitions in super-Wison loops and prove their
factorized form suggested earlier.Comment: 51 pages, 15 figure
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