3,098 research outputs found

    Quantum Kaleidoscopes and Bell's theorem

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    A quantum kaleidoscope is defined as a set of observables, or states, consisting of many different subsets that provide closely related proofs of the Bell-Kochen-Specker (BKS) and Bell nonlocality theorems. The kaleidoscopes prove the BKS theorem through a simple parity argument, which also doubles as a proof of Bell's nonlocality theorem if use is made of the right sort of entanglement. Three closely related kaleidoscopes are introduced and discussed in this paper: a 15-observable kaleidoscope, a 24-state kaleidoscope and a 60-state kaleidoscope. The close relationship of these kaleidoscopes to a configuration of 12 points and 16 lines known as Reye's configuration is pointed out. The "rotations" needed to make each kaleidoscope yield all its apparitions are laid out. The 60-state kaleidoscope, whose underlying geometrical structure is that of ten interlinked Reye's configurations (together with their duals), possesses a total of 1120 apparitions that provide proofs of the two Bell theorems. Some applications of these kaleidoscopes to problems in quantum tomography and quantum state estimation are discussed.Comment: Two new references (No. 21 and 22) to related work have been adde

    Short-wavelength secondary instabilities in homogeneous and stably stratified shear flows

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    We present a numerical investigation of three-dimensional, short-wavelength linear instabilities in Kelvin-Helmholtz (KH) vortices in homogeneous and stratified environments. The base flow, generated using two-dimensional numerical simulations, is characterized by the Reynolds number and the Richardson number defined based on the initial one-dimensional velocity and buoyancy profiles. The local stability equations are then solved on closed streamlines in the vortical base flow, which is assumed quasi-steady. For the unstratified case, the elliptic instability at the vortex core dominates at early times, before being taken over by the hyperbolic instability at the vortex edge. For the stratified case, the early time instabilities comprise a dominant elliptic instability at the core and a hyperbolic instability strongly influenced by stratification at the vortex edge. At intermediate times, the local approach shows a new branch of instability (convective branch) that emerges at the vortex core and subsequently moves towards the vortex edge. A few more convective instability branches appear at the vortex core and move away, before coalescing to form the most unstable region inside the vortex periphery at large times. The dominant instability characteristics from the local approach are shown to be in good qualitative agreement with results from global instability studies for both homogeneous and stratified cases. Compartmentalized analyses are then used to elucidate the role of shear and stratification on the identified instabilities. The role of buoyancy is shown to be critical after the primary KH instability saturates, with the dominant convective instability shown to occur in regions with the strongest statically unstable layering. We conclude by highlighting the potentially insightful role that the local approach may offer in understanding the secondary instabilities in other flows.Comment: Submitted to J. Fluid Mech., 20 pages, 10 figure

    Ant Species Richness Around Amravati City Maharashtra, India

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    Ants deserve a special place in the study of ecology, including behavior, given their species richness, social habits, and high densities, contributing to much of the animal biomes on earth (Gadagkar et.at. 1993). As ants can be studied virtually everywhere from forest interiors below ground, right up to the kitchen, we attempted a study to assess the ant species richness in a variety of habitats in and around Amravati city. The prime objective of this study is to prepare a partial checklist of ants of Amravati and to compare species richness between selected study sites. Eight study sites with different levels and types of vegetation were selected for the study.
We employed an “all out search” method for collection in the months of June and July 2010. Ants were hand collected using a brush and forecep during the day time for 6 hrs at each study site. Collected samples were preserved in 70% alcohol in the Department of Zoology, Govt. Vidarbha Institute of Science & Humanities, Amravati.
We identified Ants up to the genus level by using a Stemi DV4 Stereo microscope based on taxonomic keys of (Holldobles & Wilson, 1990; Bolton, 1994; Mathew & R.N. Tiwari, 2000).
During the present study a total of 34 species of 20 genera have been recognized from Amravati city representing five subfamilies namely Myrmicinae, Formicinae, Ponerinae, Dolichoderinae and Pseudomyrmicinae. Out of this subfamily, Myrmicinae is the most abundant having 11 genera including the genus Rhoptromyrmex. It has been recorded for the first time in this region, followed by Formicinae with four genera for being recorded for the first time as genus Oecophylla. Subfamily Ponerinae and Dolichoderinae were recorded only with two genera each; while the subfamily Pseudomyrmicinae where recorded very poorly with only one genera from G.V.I.S.H. campus.
Few ant genera such as Crematogaster and Myrmicaria of subfamily Myrmicinae, Camponotus and Polyrhachis of subfamily Formicinae and Leptogenys of subfamily Ponerinae were mostly found in all the habitats and most localities. Few genera are confined to few localities or habitat types, such as Rhoptromyrmex and Oecophylla recorded only from Pohara forests. Genus Tetraponera of subfamily Pseudomyrmicinae were collected from the tree trunk of Azadirakhta indica in the G.V.I.S.H. campus. 
Comparison of ant species distribution between the different study sites revealed that ant species richness was highest in Pohara forest with 28 species & lowest with 9 species around urban areas. Relatively high ant species richness was recorded at all the study sites such as the Agriculture field, Tree plantation area, and the Wadali and Chhatri Garden. On the other hand, ant species richness was low around urban houses compared to rural houses due to little or no vegetation and high levels of disturbance. The tree plantation site, roads, and pavement showed higher numbers of ant species compared to around urban areas probably due to road side richness of tree plantation.
From this study we conclude that due to availability of food and shelter, richness of ant species increases in forest and tree plantation areas. The number of ant species declines in low vegetative areas including urban areas. It is possible to study the ecology and biodiversity of living faunas by the studying the habitats of ants. The environs of Amravati city are rich in Ant fauna which deserve further study

    Spread of Folk Worship: Paappaaththi Amman

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    The spread of a cult system from one place to another is called cult diffusion. This article explains the factors behind the spread of Papathi Amman worship in Chennai, which is followed in southern districts. It records the historical background given orally for the origin of the worship of Goddess Papathi. It also mentions about the location of Papathi Amman. In the context of Sanskritization, the worship of Goddess Papathi is explained by the expansion of Natar worship. It has been said that the worship of Goddess Papapati, cannot be included in the definition of religions. Attempts to institutionalize the Natar deities along with the Vedic deities have been explained, and the Natar deities are not worshiped as temples. The developmental stage of Papathi Amman as elevation is described in this article. The spread of Natar cults is due to various factors. The factors responsible for the spread of Papatti Amman worship are examined by highlighting three main factors. This article examines in detail the spread of Papathi Amman worship in the background of Sanskritization and Vedicization

    Allelic Frequency of ABO And Rh D Blood Group Among The Banjara Backward Caste of Yavatmal District, Maharashtra , India

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    The distribution of ABO blood groups and Rh(D) factor has been studied among the Banjara of Backward population of Yavatmal (Maharashtra). The A, B, O and AB blood group percentage were recorded as 24.54%, 33.82%, 29.64% and 12% respectively. The allele frequencies of O, A, B and AB groups in the combined data were found to be 0.5354, 0.2022 and 0.2624 respectively. The distribution of Rh(D) group varies among the ABO blood groups. The Rh(D) positive allelic frequency was 0.8405 and the Rh(D) negative incidence was recorded as 02.55% in the studied population

    Departmental Unity in Venpamalai: Magadpar Kanchi

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    In the development of objective grammar, the primary thread material is Venpamalai. It is a post-archaeological grammar text written after Tholkkapiyam. Magadpar Kanchi is the special sector in Venpamalai. Following Tholkkapiyam this sector took place in Venpamalai. This article is about the ideals of this sector. This article compares the Nochi and Uzhinnai sector which is next to Kanji’s Magadpar sector. These sectors have also been investigated with other departments. In order to know the influencing factors of these three sectors, the backgrounds of the sectors and departments departments are explained separately. Though this article explains about the comparison of these sectors it also traces the growth of these sectors based on the grammatical tradition

    The effect of early dark matter halos on reionization

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    The annihilation of dark matter particles releases energy, ionizing some of the gas in the Universe. We investigate the effect of dark matter halos on reionization. We show that the effect depends on the assumed density profile, the particle mass, and the assumed minimum halo mass. For NFW halos and typical WIMPs, we find the effect to be quite small. However, light dark matter candidates in the MeV range can contribute significantly to reionization and can make an important contribution to the measured optical depth. This effect may be used to constrain light dark matter models. We also study the effect of varying the halo density profile on reionization.Comment: Minor changes from v2. Accepted for publication in Phys. Rev.

    The generalized Kochen-Specker theorem

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    A proof of the generalized Kochen-Specker theorem in two dimensions due to Cabello and Nakamura is extended to all higher dimensions. A set of 18 states in four dimensions is used to give closely related proofs of the generalized Kochen-Specker, Kochen-Specker and Bell theorems that shed some light on the relationship between these three theorems.Comment: 5 pages, 1 Table. A new third paragraph and an additional reference have been adde
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