2,604 research outputs found
On the area expectation values in area tensor Regge calculus in the Lorentzian domain
Wick rotation in area tensor Regge calculus is considered. The heuristical
expectation is confirmed that the Lorentzian quantum measure on a spacelike
area should coincide with the Euclidean measure at the same argument. The
consequence is validity of probabilistic interpretation of the Lorentzian
measure as well (on the real, i.e. spacelike areas).Comment: LaTeX, 7 pages, introduction and discussion given in more detail,
references adde
Unified Brane Gravity: Cosmological Dark Matter from Scale Dependent Newton Constant
We analyze, within the framework of unified brane gravity, the weak-field
perturbations caused by the presence of matter on a 3-brane. Although deviating
from the Randall-Sundrum approach, the masslessness of the graviton is still
preserved. In particular, the four-dimensional Newton force law is recovered,
but serendipitously, the corresponding Newton constant is shown to be
necessarily lower than the one which governs FRW cosmology. This has the
potential to puzzle out cosmological dark matter. A subsequent conjecture
concerning galactic dark matter follows.Comment: 6 pages, to be published in Phys. Rev.
Degeneracies when T=0 Two Body Interacting Matrix Elements are Set Equal to Zero : Talmi's method of calculating coefficients of fractional parentage to states forbidden by the Pauli principle
In a previous work we studied the effects of setting all two body T=0 matrix
elements to zero in shell model calculations for Ti (Sc) and
Ti. The results for Ti were surprisingly good despite the
severity of this approximation. In this approximation degeneracies arose in the
T=1/2 I= and states in Sc and the T=1/2
, , and in Sc. The T=0
, , , and states in Ti were degenerate as
well. The degeneracies can be explained by certain 6j symbols and 9j symbols
either vanishing or being equal as indeed they are. Previously we used Regge
symmetries of 6j symbols to explain these degeneracies. In this work a simpler
more physical method is used. This is Talmi's method of calculating
coefficients of fractional parentage for identical particles to states which
are forbidden by the Pauli principle. This is done for both one particle cfp to
handle 6j symbols and two particle cfp to handle 9j symbols. The states can be
classified by the dual quantum numbers ()
Interferon alpha suppresses alphaherpesvirus immediate early protein levels in sensory neurons, leading to the establishment of a latent infection
Alphaherpesviruses are a subfamily of the herpesviruses containing closely related human and animal pathogens,
including human herpes simplex virus (HSV-1) and porcine pseudorabies virus (PRV)
Quantum scale invariance on the lattice
We propose a scheme leading to a non-perturbative definition of lattice field
theories which are scale-invariant on the quantum level. A key idea of the
construction is the replacement of the lattice spacing by a propagating
dynamical field -- the dilaton. We describe how to select non-perturbatively
the phenomenologically viable theories where the scale invariance is broken
spontaneously. Relation to gravity is also discussed.Comment: 5 page
Indications for Criticality at Zero Curvature in a 4d Regge Model of Euclidean Quantum Gravity
We re-examine the approach to four-dimensional Euclidean quantum gravity
based on the Regge calculus. A cut-off on the link lengths is introduced and
consequently the gravitational coupling and the cosmological constant become
independent parameters. We determine the zero curvature, , line in the
coupling constant plane by numerical simulations. When crossing this line we
find a strong, probably first order, phase transition line with indications of
a second order endpoint. Beyond the endpoint the transition through the line appears to be a crossover. Previous investigations, using the Regge or
the Dynamical Triangulation approach, dealt with a limit in which the first
order transition prevails.Comment: Contribution to the lattice 2003 Tsukuba symposiu
Measure dependence of 2D simplicial quantum gravity
We study pure 2D Euclidean quantum gravity with interaction on
spherical lattices, employing Regge's formulation. We attempt to measure the
string susceptibility exponent by using a finite-size
scaling Ansatz in the expectation value of . To check on effects of the
path integral measure we investigate two scale invariant measures, the
"computer" measure and the Misner measure .Comment: 3 pages, self unpacking uuencoded PostScript file, contribution to
LATTICE9
Oddballs and a Low Odderon Intercept
We report an odderon Regge trajectory emerging from a field theoretical
Coulomb gauge QCD model for the odd signature JPC (P=C= -1) glueball states
(oddballs). The trajectory intercept is clearly smaller than the pomeron and
even the omega trajectory's intercept which provides an explanation for the
nonobservation of the odderon in high energy scattering data. To further
support this result we compare to glueball lattice data and also perform
calculations with an alternative model based upon an exact Hamiltonian
diagonalization for three constituent gluons.Comment: 4 pages, 2 figures, 1 tabl
- …
