Ordinary atom-mirror atom bound states: A new window on the mirror world

Mirror symmetry is a plausible candidate for a fundamental symmetry of particle interactions which can be exactly conserved if a set of mirror particles exist. The properties of the mirror particles seem to provide an excellent candidate to explain the inferred dark matter of the Universe and might also be responsible for a variety of other puzzles in particle physics, astrophysics, meteoritics and planetary science. One such puzzle -- the orthopositronium lifetime problem -- can be explained if there is a small kinetic mixing of ordinary and mirror photons. We show that this kinetic mixing implies the existence of ordinary atom - mirror atom bound states with interesting terrestrial and astrophysical implications. We suggest that sensitive mass spectroscopic studies of ordinary samples containing heavy elements such as lead might reveal the presence of these bound states, as they would appear as anomalously heavy elements. In addition to the effects of single mirror atoms, collective effects from embedded fragments of mirror matter (such as mirror iron microparticles) are also possible. We speculate that such mirror matter fragments might explain a mysterious UV photon burst observed coming from a laser irradiated lead target in a recent experiment.Comment: about 8 pages, couple of change

Dreibein as prepotential for three-dimensional Yang-Mills theory

We advocate and develop the use of the dreibein (and the metric) as prepotential for three-dimensional SO(3) Yang-Mills theory. Since the dreibein transforms homogeneously under gauge transformation, the metric is gauge invariant. For a generic gauge potential, there is a unique dreibein on fixing the boundary condition. Topologically non-trivial monopole configurations are given by conformally flat metrics, with scalar fields capturing the monopole centres. Our approach also provides an ansatz for the gauge potential covering the topological aspects.Comment: 13 pages, improved version, section on Jacobian remove

Tools for reformulating logical forms into zero-one mixed integer programs (MIPS)

A systematic procedure for transforming a set of logical statements or logical conditions imposed on a model into an Integer Linear Programming (ILP) formulation or a Mixed Integer Programming (MIP) formulation is presented. A reformulation procedure which uses the extended reverse polish representation of a compound logical form is then described. A prototype user interface by which logical forms can be reformulated and the corresponding MIP constructed and analysed within an existing Mathematical Programming modelling system is illustrated. Finally, the steps to formulate a discrete optimisation model in this way are demonstrated by means of an example

Multiscale Morphological Filtering for Analysis of Noisy and Complex Images

Images acquired with passive sensing techniques suffer from illumination variations and poor local contrasts that create major difficulties in interpretation and identification tasks. On the other hand, images acquired with active sensing techniques based on monochromatic illumination are degraded with speckle noise. Mathematical morphology offers elegant techniques to handle a wide range of image degradation problems. Unlike linear filters, morphological filters do not blur the edges and hence maintain higher image resolution. Their rich mathematical framework facilitates the design and analysis of these filters as well as their hardware implementation. Morphological filters are easier to implement and are more cost effective and efficient than several conventional linear filters. Morphological filters to remove speckle noise while maintaining high resolution and preserving thin image regions that are particularly vulnerable to speckle noise were developed and applied to SAR imagery. These filters used combination of linear (one-dimensional) structuring elements in different (typically four) orientations. Although this approach preserves more details than the simple morphological filters using two-dimensional structuring elements, the limited orientations of one-dimensional elements approximate the fine details of the region boundaries. A more robust filter designed recently overcomes the limitation of the fixed orientations. This filter uses a combination of concave and convex structuring elements. Morphological operators are also useful in extracting features from visible and infrared imagery. A multiresolution image pyramid obtained with successive filtering and a subsampling process aids in the removal of the illumination variations and enhances local contrasts. A morphology-based interpolation scheme was also introduced to reduce intensity discontinuities created in any morphological filtering task. The generality of morphological filtering techniques in extracting information from a wide variety of images obtained with active and passive sensing techniques is discussed. Such techniques are particularly useful in obtaining more information from fusion of complex images by different sensors such as SAR, visible, and infrared

On the construction of a digital transfer function from its real part on unit circle

It is shown in this correspondence that the system function H(z) of a linear time invariant (LTI) causal digital filter with real impulse response coefficients can be obtained from the real part of its frequency response HR(ejω) given in the form of a rational trigonomentric function, using algebraic methods rather than complex contour integration techniques

CMB power spectrum estimation using noncircular beams

The measurements of the angular power spectrum of the Cosmic Microwave Background (CMB) anisotropy has proved crucial to the emergence of cosmology as a precision science in recent years. In this remarkable data rich period, the limitations to precision now arise from the the inability to account for finer systematic effects in data analysis. The non-circularity of the experimental beam has become progressively important as CMB experiments strive to attain higher angular resolution and sensitivity. We present an analytic framework for studying the leading order effects of a non-circular beam on the CMB power spectrum estimation. We consider a non-circular beam of fixed shape but variable orientation. We compute the bias in the pseudo-$C_l$ power spectrum estimator and then construct an unbiased estimator using the bias matrix. The covariance matrix of the unbiased estimator is computed for smooth, non-circular beams. Quantitative results are shown for CMB maps made by a \emph{hypothetical} experiment with a non-circular beam comparable to our fits to the WMAP beam maps described in the appendix and uses a \emph{toy} scan strategy. We find that significant effects on CMB power spectrum can arise due to non-circular beam on multipoles comparable to, and beyond, the inverse average beam-width where the pseudo-$C_l$ approach may be the method of choice due to computational limitations of analyzing the large datasets from current and near future CMB experiments.Comment: 23 pages, 12 eps figures, uses RevTeX 4. Matches version accepted to Phys. Rev. D. Corrected minor typographical error in the final expression [eqn (3.23)] (post publication

Trade liberalization, fiscal adjustment, and exchange rate policy in India

The authors investigate the impact of India's program of economic stabilization and trade liberalization launched in 1991, a year when the country was in the throes of a foreign exchange crisis. The authors address a key policy tradeoff between trade liberalization and fiscal adjustment arising from India's heavy dependence on tariffs for public revenues. They give quantitative expression to how trade liberalization should be coordinated both with fiscal adjustment - that is, a combination of trade-neutral tax increases and expenditure reduction and with a policy of exchange rate changes to restore both internal and external equilibrium. This paper asks: What is the impact of a reduction in the fiscal deficit characteristic of stabilization programs on tax and expenditure levels, on the real exchange rate, and the current account deficit? What is the effect of a significant trade liberalization without additional external financing on macroeconomic variables such as the required degree of fiscal adjustment and change in the real exchange rate, and, at a more disaggregated level, on output levels in different export-oriented and import-substituting sectors of the economy? What would the impact of such trade liberalization look like should substantive external financing become available without the need for domestic fiscal adjustment? The questions are explored using a general equilibrium model of the Indian economy that focuses on the consequences of trade policy reform. Policymakers are, however, also interested in how various import-substituting industries would be adversely affected by trade liberalization and how particular export-oriented industries would gain from it. These objectives are reconciled by the innovative expedient of implementing two models on a common data base: 1) a disaggregated 72-sector (price sensitive) input-output version that makes simplified assumptions regarding certain economywide relationships; and 2) an aggregated 6-sector version that pays attention to those relationships and can suggest what corrections ought to be made to the results of the sectorally disaggregated analysis. The policy questions were answered for the eve of the 1991 economic reform program launched by India's policymakers. Developments in the principal macroeconomic aggregates in the first two years of the liberalization process were then compared with the outcomes of the model and generally found to correspond closely. This finding encouraged an updating of the model for fiscal 1992-93 and its deployment to analyze the consequences of a set of further economic reforms for subsequent years. The authors conclude by suggesting that the approach developed for this paper could provide broad indications of the economywide and sectoral consequences of pursuing the unfinished agenda of reforms facing policymakers not only in India but in other developing countries as well.Payment Systems&Infrastructure,Environmental Economics&Policies,Labor Policies,Economic Theory&Research,Consumption,EnvironmentalEconomics&Policies,Economic Theory&Research,Economic Stabilization,TF054105-DONOR FUNDED OPERATION ADMINISTRATION FEE INCOME AND EXPENSE ACCOUNT,Consumption

Quantum Information Paradox: Real or Fictitious?

One of the outstanding puzzles of theoretical physics is whether quantum information indeed gets lost in the case of Black Hole (BH) evaporation or accretion. Let us recall that Quantum Mechanics (QM) demands an upper limit on the acceleration of a test particle. On the other hand, it is pointed out here that, if a Schwarzschild BH would exist, the acceleration of the test particle would blow up at the event horizon in violation of QM. Thus the concept of an exact BH is in contradiction of QM and quantum gravity (QG). It is also reminded that the mass of a BH actually appears as an INTEGRATION CONSTANT of Einstein equations. And it has been shown that the value of this integration constant is actually zero. Thus even classically, there cannot be finite mass BHs though zero mass BH is allowed. It has been further shown that during continued gravitational collapse, radiation emanating from the contracting object gets trapped within it by the runaway gravitational field. As a consequence, the contracting body attains a quasi-static state where outward trapped radiation pressure gets balanced by inward gravitational pull and the ideal classical BH state is never formed in a finite proper time. In other words, continued gravitational collapse results in an "Eternally Collapsing Object" which is a ball of hot plasma and which is asymptotically approaching the true BH state with M=0 after radiating away its entire mass energy. And if we include QM, this contraction must halt at a radius suggested by highest QM acceleration. In any case no EH is ever formed and in reality, there is no quantum information paradox.Comment: 8 pages in Pramana Style, 6 in Revtex styl

Altitude distribution, origin and flux of sodium in the atmosphere

Sodium equilibrium altitude distribution, origin, and flux calculated for earth atmospher