Evidence is presented which indicates that almost all HCGs are dynamically associated with generally elongated loose groups of galaxies, and are compact cores of the latter. Most of those loose groups, the direction of elongation of which lies at angles close to 45◦ with the line of sight, were revealed by previous investigations. Hence, HCGs have, probably, longer life-times than it has been d...

Higher–dimensional theories imply that some constants, such as the gravitational constant and the strength of the gauge–couplings, are not fundamental constants. Instead they are related to the sizes of the extra–dimensional space, which are moduli fields in the four– dimensional effective theory. We study the cosmological evolution of the moduli fields appearing in brane world scenarios and di...

According to the Brans–Dicke theory, the value of the gravitational constant G which we measure at present is determined by the value of the Brans–Dicke scalar field φ at the end of inflation. However, due to quantum fluctuations of the scalar fields produced during inflation, the gravitational constant G(φ) may take different values in different exponentially large parts of the Universe. We in...

The basic motivation of this work is to attempt to explain the rapid primordial inflation and the observed slow late-time inflation by using the BransDicke theory of gravity. We show that the ratio of these two inflation parameters is proportional to the square root of the Brans-Dicke parameter ω (ω ≫ 1). We also calculate the Hubble parameter H and the time variation of the time dependent Newt...

The quantum state of a wormhole can be represented by a path integral over all asymptotically Euclidean four-geometries and all matter fields which have prescribed values, the arguments of the wave function, on a three-surface S which divides the spacetime manifold into two disconnected parts. The ground-state wave function is picked out by requiring that there be no matter excitations in the a...

For nanoparticle-based technologies, efficient and rapid approaches that yield particles of high purity with a specific shape and size are critical to optimize the nanostructure-dependent optical, electrical, and magnetic properties, and not bias conclusions due to the existence of impurities. Notwithstanding the continual improvement of chemical methods for shaped nanoparticle synthesis, bypro...

[1] The dependency of nonsphericity on gravitational settling of mineral dust particles is parameterized for prolate ellipsoids and Reynolds number lower than 2. The settling speed is numerically solved from the momentum equation as a function of particle diameter and aspect ratio. The reduction of settling speed due to nonsphericity is included in the Global Ozone Chemistry Aerosol Radiation a...

Although branched and linear polyethylenimines (bPEIs and lPEIs) are gold standard transfectants, a systematic analysis of the effects of the preparation protocol of polyplexes and the composition of the transfection medium on their physicochemical behaviour and effectiveness in vitro have been much neglected, undermining in some way the identification of precise structure-function relationship...

Face-centered cubic single crystals of σ=1.55 μm diameter hard-sphere silica colloidal particles were prepared by sedimentation onto (100) and (110) oriented templates. The crystals had a wide interface with the overlaying liquid that was parallel to the template. The location of the interface was determined by confocal microscopic location of the particles, followed by identification of the cr...

In Brans–Dicke theory the Universe becomes divided after inflation into many exponentially large domains with different values of the effective gravitational constant. Such a process can be described by diffusion equations for the probability of finding a certain value of the inflaton and dilaton fields in a physical volume of the Universe. For a typical chaotic inflation potential, the solutio...