Institute of Theoretical Physics, U. of Tübingen, D-72070 Tübingen, Germany (Dated: February 2, 2008) Abstract A semi-perturbative calculation of the ghost-gluon vertex in Landau gauge Yang-Mills theory in four and three Euclidean space-time dimensions is presented. Non-perturbative gluon and ghost propagators are employed, which have previously been calculated from a truncated set of Dyson– Sc...

Solution methods for the compressible Navier-Stokes equations based on finite volume discretizations often implement boundary conditions using ghost cells outside of the computational domain. Filling the ghost cells using straightforward zerothor first-order extrapolation, while computationally expedient, is well-known to fail even for some simple flows, especially when turbulent structures int...

We show that a finite non-vanishing ghost dressing function at zero momentum satisfies the scaling properties of the ghost propagator Schwinger-Dyson equation. This kind of Schwinger-Dyson solutions may well agree with lattice data and provides an interesting alternative to the widely spread claim that the gluon dressing function behaves like the inverse squared ghost dressing function, a claim...

Introduction: Ghost magnetic resonance angiography (MRA) has been proposed as an unenhanced and ungated method for angiography that is based on the presence of ghost artifacts resulting from pulsatile blood flow (1). Although the method is simple to acquire in that cardiac gating is not required, it requires manual post-processing to identify suitable slices in a large stack from which to creat...

Introduction: Ghost magnetic resonance angiography (MRA) is a new method for angiography that suppresses background tissue without subtraction. The method is predicated on the creation of arterial ghost artifacts within a region containing no MR signal (e.g. air), and can be used for both unenhanced and contrast-enhanced MRA. When used for unenhanced MRA, cardiac gating is not required. This ca...

This paper deals with a method for removing a ghost target that is not a real object from the output of a multiple object-tracking algorithm. This method uses an artificial neural network (multilayer perceptron) and introduces a structure, learning, verification, and evaluation method for the artificial neural network. The implemented system was tested at an intersection in a city center. Resul...

Differential Power Analysis (DPA) attacks extract secret key information from cryptographic devices by comparing power consumption with predicted values based on key candidates and looking for peaks which indicate a correct prediction. A general obstacle in the use of DPA is the occurrence of so called ghost peaks, which may appear when evaluating incorrect key candidates. Some ghost peaks can ...

We examine the possibility that there may exist a logarithmic correction to the infrared asymptotic solution with power behavior which has recently been found for the gluon and Faddeev-Popov ghost propagators in the Landau gauge. We propose a new Ansatz to find a pair of solutions for the gluon and ghost form factors by solving the coupled Schwinger-Dyson equation under a simple truncation. Thi...

In the setup of ghost condensation model the generalized second law of black hole thermodynamics can be respected under a radiatively stable assumption that couplings between the field responsible for ghost condensate and matter fields such as those in the Standard Model are suppressed by the Planck scale. Since not only black holes but also cosmology are expected to play important roles toward...

Quantum Ghost Imaging by Measuring Reflected Photons R. E. Meyers1 and K. S. Deacon1 Summary A new type of imaging, Quantum ghost imaging, is described that is based on the measurement of photons reflected from an object . A CCD array is placed facing a chaotic light source and gated by a photon counting detector that simply counts all randomly reflected photons from an object. A “ghost” image ...