A Model for Large theta13 Constructed using the Eigenvectors of the S4 Rotation Matrices

A procedure for using the eigenvectors of the elements of the representations of a discrete group in model building is introduced and is used to construct a model that produces a large reactor mixing angle, sin^2(theta13)=2/3 sin^2(pi/16), in agreement with recent neutrino oscillation observations. The model fully constrains the neutrino mass ratios and predicts normal hierarchy with the light neutrino mass, m1~25 meV. Motivated by the model, a new mixing ansatz is postulated which predicts all the mixing angles within 1sigma errors.Comment: 6 pages, 1 figure, contribution to the proceedings of DISCRETE 2012 to appear in the open access Journal of Physics: Conference Series (JPCS), preprint typeset in two-column revtex4 styl

TM1\text{TM}_1 neutrino mixing with sin⁡θ13=13sin⁡π12\sin \theta_{13}=\frac{1}{\sqrt{3}}\sin \frac{\pi}{12}

We construct a neutrino model using the flavour group $S_4\times C_4 \times C_3$ under the type-1 seesaw mechanism. The vacuum alignments of the flavons in the model lead to $\text{TM}_1$ mixing with $\sin \theta_{13}=\frac{1}{\sqrt{3}}\sin \frac{\pi}{12}$. The mixing also exhibits $\mu\text{-}\tau$ reflection symmetry. By fitting the eigenvalues of the effective seesaw mass matrix with the observed neutrino mass-squared differences, we predict the individual light neutrino masses. The vacuum alignment of the $S_4$ triplet appearing in the Majorana mass term plays a key role in obtaining the aforementioned $\text{TM}_1$ scenario. Since the symmetries of the flavour group are not sufficient to define this alignment, we apply the recently proposed framework of the auxiliary group in our model. Using this framework, the $S_4$ triplet is obtained by coupling together several irreducible multiplets that transform under an expanded flavour group consisting of the original flavour group as well as an auxiliary group. The vacuum alignment of each of these multiplets is uniquely defined in terms of its residual symmetries under the expanded flavour group. As a result, the $S_4$ triplet constructed from these multiplets also becomes uniquely defined.Comment: 17 pages, 5 figure

Structure, Conduct and Performance of Value Chain in Seaweed farming in India

Among the three types of technologies available in the fisheries sector in India, seaweed farming, initially promoted as a livelihood option, has emerged as the one area which probably has the maximum potential for up-scaling. This paper has examined the structure, conduct and performance of the value chain in seaweed farming in India inquiring into the production, institutional, marketing, social and community relationships in small-scale seaweed farming in the Ramanathapuram district of Tamil Nadu and the concept of self-help groups (SHG) as an increasingly workable option for coastal resources management. The value chain analysis of the sector has substantially proved that committed and synergistic production, marketing and institutional arrangements enabled by corporate leadership, offers considerable savings in transaction costs. The SHG model has also shown strong gender orientation in the initial years of seaweed culture in the district contributing to strong structural foundations to the movement. The seaweed sector in the coastal India has all the potential to rise from the low-income conditions normally associated with basic livelihood activities to higher levels of employment-income-consumption relationships.Agricultural and Food Policy,

Giant coherence in driven systems

We study the noise-induced currents and reliability or coherence of transport in two different classes of rocking ratchets. For this, we consider the motion of Brownian particles in the over damped limit in both adiabatic and non-adiabatic regimes subjected to unbiased temporally symmetric and asymmetric periodic driving force. In the case of a time symmetric driving, we find that even in the presence of a spatially symmetric simple sinusoidal potential, highly coherent transport occurs. These ratchet systems exhibit giant coherence of transport in the regime of parameter space where unidirectional currents in the deterministic case are observed. Outside this parameter range, i.e., when current vanishes in the deterministic regime, coherence in transport is very low. The transport coherence decreases as a function of temperature and is a non-monotonic function of the amplitude of driving. The transport becomes unreliable as we go from the adiabatic to the non-adiabatic domain of operation.Comment: 15 pages, 9 figures, replaced by the version to appear in JSTA

An approach to distributed execution of Ada programs

Intelligent control of the Space Station will require the coordinated execution of computer programs across a substantial number of computing elements. It will be important to develop large subsets of these programs in the form of a single program which executes in a distributed fashion across a number of processors. A translation strategy for distributed execution of Ada programs in which library packages and subprograms may be distributed is described. A preliminary version of the translator is operational. Simple data objects (no records or arrays as yet), subprograms, and static tasks may be referenced remotely

Dynamical Horizons: Energy, Angular Momentum, Fluxes and Balance Laws

Dynamical horizons are considered in full, non-linear general relativity. Expressions of fluxes of energy and angular momentum carried by gravitational waves across these horizons are obtained. Fluxes are local, the energy flux is positive and change in the horizon area is related to these fluxes. The flux formulae also give rise to balance laws analogous to the ones obtained by Bondi and Sachs at null infinity and provide generalizations of the first and second laws of black hole mechanics.Comment: 4 pages, RevTeX4. Minor typos corrected. To appear in Phys.Rev.Let

Homogeneous linear intrinsic constraints in the stationary manifold of a GG-invariant potential

The stationary points of a potential $\mathcal{V}$, constructed with a scalar multiplet $\varphi$ and having the symmetry group $G$, appear as stationary $G$-orbits. A connected component of a stationary $G$-orbit is called a stationary manifold. By removing some invariant terms from $\mathcal{V}$, we construct $\tilde{\mathcal{V}}$ having the symmetry group $\tilde{G}$. We define $\tilde{H}$ as the pointwise stabilizer of a stationary manifold of $\mathcal{V}$ under $\tilde{G}$. We discover that $\tilde{H}$ is unaffected by any change in the coefficients of the terms in $\mathcal{V}$ if the terms are "compatible with $\tilde{H}$". In relation to $\tilde{H}$, we obtain a set of homogenous linear equations that constrain the components of every stationary point in the stationary manifold independently of the coefficients. We call these equations homogeneous linear intrinsic constraints (HLICs). HLICs in a stationary point manifest as HLICs in the corresponding vacuum alignment of $\varphi$, which plays a central role in building predictive phenomenological models. In this paper, we develop a procedure that involves splitting $\mathcal{V}$ into smaller parts to establish the existence of specific stationary manifolds using arguments based on symmetries alone. Since this procedure does not require explicit extremization of the potential, it can be a valuable tool in mathematical physics. In this procedure, we first consider the various irreducible multiplets (irreps) in $\varphi$ separately and then analyze the cross terms among the irreps using the compatibility condition. Subsequently, we obtain $\tilde{H}$ as the direct product of the stabilizers corresponding to the irreps in $\varphi$.Comment: 24 pages which include 15 pages of appendix, 7 figures which include 4 figures in the appendi