On Symmetry Non-Restoration at High Temperature

We study the effect of next-to-leading order contributions on the phenomenon of symmetry non-restoration at high temperature in an $O(N_1)\times O(N_2)$ model.Comment: 8 pages. Two figures in a separate fil

Sterile Neutrinos: Phenomenology and Theory

A sterile neutrino in addition to the three known neutrinos seems unavoidable if one wants a simultaneous understanding of the results of the LSND experiment indicating $\nu_{\mu}-\nu_e$ oscillation together with other evidences for neutrino oscillations such as those from solar and atmospheric neutrino deficits. A major theoretical challenge then is to understand why the sterile neutrino is so light. A simple solution appears to be to assume that it is the lightest neutrino of a mirror sector of the universe which has identical matter and gauge content as the standard model. After a brief review of the phenomenology, a recently constructed realistic grand unified model based on the gauge group $SO(10)\times SO(10)^\prime$ that embeds the mirror universe idea is presented. Detailed predictions for known and the sterile neutrino sector are given and their consequences for cosmology are mentioned.Comment: Invited talk presented at the workshop on "New trends in neutrino physics" held at the Ringberg Castle, Germany, May 24-28, 1998; 10 page

CP violation in the lepton sector with Majorana neutrinos

We study CP violation in the lepton sector in extended models with right-handed neutrinos, without and with left-right symmetry, and with arbitrary mass terms. We find the conditions which must be satisfied by the neutrino and charged lepton mass matrices for CP conservation. These constraints, which are independent of the choice of weak basis, are proven to be also sufficient in simple cases. This invariant formulation makes apparent the necessary requirements for CP violation, as well as the size of CP violating effects. As an example, we show that CP violation can be much larger in left-right symmetric models than in models with only additional right-handed neutrinos, {\it i.e.}, without right-handed currents.Comment: 19 page

Scaling in the Neutrino Mass Matrix

In an attempt to uncover any underlying structure in the neutrino mass matrix, we discuss the possibility that the ratios of elements of its Majorana mass matrix are equal. We call this "strong scaling Ansatz" for neutrino masses and study its phenomenological implications. Of three possible independent scale invariant possibilities, only one is allowed by current data, predicting in a novel way the vanishing of U_{e3} and an inverted hierarchy with the lightest neutrino having zero mass. The Ansatz has the additional virtue that it is not affected by renormalization running. We also discuss explicit models in which the scaling Ansatz is realized.Comment: 13 pages, 2 figures. To appear in PL

Decentralised governance and planning in India: case study of a tribal district

This paper examines the process of the formulation of decentralised planning in the Tribal regions of Odisha, a state located in eastern part of India, while examining the powers devolved to the local governments in such regions in the state to formulate plan, and the ground reality of the preparation of such plans in the context of the implementation of the Provisions of Panchayats (Extension to Scheduled Areas) Act (PESA Act). Formulation of decentralised planning in Odisha was taken up in the year 2008. However, based on the secondary data and interacting with the various people in field, the paper has revealed that “structural impediments” and “functional incapacity” of the local governments in the Scheduled Areas have hampered the spirit of such institutions with regard to the planning and implementation of the development programs. The paper argues that decentralised plans should be realistic, based on the effective utilisation of local resources, and the local development issues should be prioritised and implemented accordingly. The paper suggests policy measures such as effective participation, prioritisation of development needs, and rationalisation of the required and available funds, considering the significance of the PESA Act. While doing so, the issues of the tribals should receive priority

Effect of inverse magnetic catalysis on conserved charge fluctuations in hadron resonance gas model

The effect of inverse magnetic catalysis (IMC) has been observed on the conserved charge fluctuations and the correlations along the chemical freeze-out curve in a hadron resonance gas model. The fluctuations and the correlations have been compared with and without charge conservations. The charge conservation plays an important role in the calculation of the fluctuations at nonzero magnetic field and for the fluctuations in the strange charge at zero magnetic field. The charge conservation diminishes the correlations $\chi_{BS}$ and $\chi_{QB}$, but enhances the correlation $\chi_{QS}$. The baryonic fluctuations (2nd order) at $B = 0.25$ ${GeV}^2$ increases more than two times compared to $B = 0$ at higher $\mu_{B}$. The fluctuations have been compared at nonzero magnetic field along the freeze-out curve i.e along fitted parameters of the chemical freeze-out temperature and chemical potentials, with the fluctuations at nonzero magnetic field along the freeze-out curve with the IMC effect, and the results are very different with the IMC effect. This is clearly seen in the products of different moments ${{\sigma}^2}/{M}$ and $S\sigma$ of net-kaon distribution.Comment: 12 pages,10 figures, Accepted by Phys. Rev.

Neutrinoless Double Beta Decay and Physics Beyond the Standard Model

The various mechanisms for neutrinoless double beta decay in gauge theories are reviewed and the present experimental data is used to set limits on physics scenarios beyond the standard model. The positive indications for nonzero neutrino masses in various experiments such as those involving solar, atmospheric and accelerator neutrinos are discussed and it is pointed out how some neutrino mass textures consistent with all data can be tested by the ongoing double beta decay experiments. Finally, the outlook for observable neutrinoless double beta decay signal in grand unified theories is discussed.Comment: 21 pages, latex; 10 figures available on request; Invited talk presented at the "International Workshop on Neutrinoless Double Beta Decay and relate topics", Trento, Italy; April, 1995; to appear in the proceedings to be published by World scientifi