35,971 research outputs found
New mechanisms of droplet coarsening in phase-separating fluid mixtures
We propose here a new mechanism of droplet coarsening in phase-separating
fluid mixtures. In contrast to the conventional understanding that there are no
interactions between droplets in the late stage of spinodal decomposition, we
demonstrate the existence of interactions between droplets that is caused by
the coupling between diffuse concentration change around droplets. We show the
possibility that this mechanism plays an important role in droplet phase
separation together with Brownian-coagulation mechanism. We also discuss the
coupling between hydrodynamic and diffusion modes, namely, "collision-induced
collision" phenomena.Comment: 5 pages, RevTex, To appear in J. Chem. Phys. Vol. 107, No.9 (1997
Generalized Equivalence Principle in Extended New General Relativity
In extended new general relativity, which is formulated as a reduction of
gauge theory of gravity whose gauge group is the covering
group of the Poincar\'e group, we study the problem of whether the total
energy-momentum, total angular momentum and total charge are equal to the
corresponding quantities of the gravitational source. We examine this for
charged axi-symmetric solutions of gravitational field equations. Our main
concern is the restriction on the asymptotic form of the gravitational field
variables imposed by the requirement that physical quantities of the total
system are equivalent to the corresponding quantities of the charged rotating
source body. This requirement can be regarded as an equivalence principle in a
generalized sense.Comment: 35 page
Single and Double Universal Seesaw Mechanisms with Universal Strength for Yukawa Couplings
Single and double universal seesaw mechanisms and the hypothesis of universal
strength for Yukawa couplings are applied to formulate a unified theory of
fermion mass spectrum in a model based on an extended Pati-Salam symmetry. Five
kinds of Higgs fields are postulated to mediate scalar interactions among
electroweak doublets of light fermions and electroweak singlets of heavy exotic
fermions with relative Yukawa coupling constants of exponential form. At the
first-order seesaw approximation, quasi-democratic mass matrices with equal
diagonal elements are derived for all charged fermion sectors and a diagonal
mass matrix is obtained for the neutrino sector under an additional ansatz.
Assuming the vacuum neutrino oscillation, the problems of solar and atmospheric
neutrino anomalies are investigated.Comment: 13 pages, LaTeX; a reference adde
Interplay of Kondo and superconducting correlations in the nonequilibrium Andreev transport through a quantum dot
Using the modified perturbation theory, we theoretically study the
nonequilibrium Andreev transport through a quantum dot coupled to normal and
superconducting leads (N-QD-S), which is strongly influenced by the Kondo and
superconducting correlations. From the numerical calculation, we find that the
renormalized couplings between the leads and the dot in the equilibrium states
characterize the peak formation in the nonequilibrium differential conductance.
In particular, in the Kondo regime, the enhancement of the Andreev transport
via a Kondo resonance occurs in the differential conductance at a finite bias
voltage, leading to an anomalous peak whose position is given by the
renormalized parameters. In addition to the peak, we show that the energy
levels of the Andreev bound states give rise to other peaks in the differential
conductance in the strongly correlated N-QD-S system. All these features of the
nonequilibrium transport are consistent with those in the recent experimental
results [R. S. Deacon {\it et al.}, Phys. Rev. Lett. {\bf 104}, 076805 (2010);
Phys. Rev. B {\bf 81}, 12308 (2010)]. We also find that the interplay of the
Kondo and superconducting correlations induces an intriguing pinning effect of
the Andreev resonances to the Fermi level and its counter position.Comment: 22 pages, 23 figure
Global agricultural, food and energy price spikes : Impacts on low income households in the United Kingdom and policy options
The authors acknowledge the support of Scottish Government ClimateXChange Centre and the Rural and Environment Science and Analytical Services Division.Peer reviewedPublisher PD
- âŠ