Double Soft Graviton Theorems and BMS Symmetries

It is now well understood that Ward identities associated to the (extended) BMS algebra are equivalent to single soft graviton theorems. In this work, we show that if we consider nested Ward identities constructed out of two BMS charges, a class of double soft factorization theorems can be recovered. By making connections with earlier works in the literature, we argue that at the sub-leading order, these double soft graviton theorems are the so-called consecutive double soft graviton theorems. We also show how these nested Ward identities can be understood as Ward identities associated to BMS symmetries in scattering states defined around (non-Fock) vacua parametrized by supertranslations or superrotations.Comment: 29 pages, minor changes added, footnote 3 removed, consistency check with Ref:22 settle

Continuous-Variable QKD with key rates far above Devetak-Winter

Continuous-Variable Quantum Key Distribution (CVQKD) at large distances has such high noise levels that the employed error-correcting codes must have very low rate. In this regime it becomes feasible to implement random-codebook error correction, which is known to perform close to capacity. We propose a random-codebook reverse reconciliation scheme for CVQKD that is inspired by spread-spectrum watermarking. Our scheme has a novel way of achieving statistical decoupling between the publicly sent reconciliation data and the secret key. We provide a theoretical analysis of the secret key rate and we present numerical results. The best performance is obtained when the message size exceeds the mutual information I(X;Y) between Alice and Bob's measurements. This somewhat counter-intuitive result is understood from a tradeoff between code rate and frame rejection rate, combined with the fact that error correction for QKD needs to reconcile only random data. We obtain secret key lengths that lie far above the Devetak-Winter value I(X;Y)-I(E;Y)

Security of a Continuous-Variable based Quantum Position Verification Protocol

In this work we study quantum position verification with continuous-variable quantum states. In contrast to existing discrete protocols, we present and analyze a protocol that utilizes coherent states and its properties. Compared to discrete-variable photonic states, coherent states offer practical advantages since they can be efficiently prepared and manipulated with current technology. We prove security of the protocol against any unentangled attackers via entropic uncertainty relations, showing that the adversary has more uncertainty than the honest prover about the correct response as long as the noise in the quantum channel is below a certain threshold. Additionally, we show that attackers who pre-share one continuous-variable EPR pair can break the protocol.Comment: 17 pages, 2 figure

Wernicke’s encephalopathy precipitated by neuromyelitis optica spectrum disorder and Graves’ disease: A tale of clinical and radiological dilemmas

Background Neuromyelitis optica spectrum disorder (NMOSD), an autoimmune astrocytopathy, may share common clinico-radiological features with Wernicke's encephalopathy (WE). A variant of NMOSD, known as area postrema syndrome (APS), that presents with intractable hiccups and associated vomiting, might lead to the depletion of nutrients if not detected and treated early. Autoimmune thyroid disorders (i.e., Graves’ disease) may be associated with NMOSD. Rarely, thyrotoxicosis can give rise to thiamine depletion and WE. Case presentation Here, we present a case of untreated hyperthyroidism in an Indian female who presented with thyrotoxicosis and later developed WE, possibly also contributed by NMOSD (APS)-induced recurrent vomiting. The patient recovered with antithyroid drugs, parenteral thiamine, and immunomodulatory therapy. The possible pathogenic mechanisms have been discussed. Conclusion Our case establishes the importance of considering NMOSD variants in metabolic encephalopathy, especially if neuroimaging is suggestive and in the backdrop of another autoimmune disorder

Stress induced creep cavity

Studies monitoring cavity nucleation with strain after creep deformation has limited information with varying applied stresses. In the present communication, a large number of experiments were performed to investigate cavity nucleation at different stresses for a primary reformer tube. It has been found that with the increase in stress, cavity formation increases drastically, which is more prone to nucleate at grain boundary triple junctions rather than grain boundaries where the extent of initial inclusions/other second phase particles was kept unaltered. (C) 2014 Elsevier B.V. All rights reserve

Neural Substrate of Group Mental Health: Insights from Multi-Brain Reference Frame in Functional Neuroimaging

Contemporary mental health practice primarily centers around the neurobiological and psychological processes at the individual level. However, a more careful consideration of interpersonal and other group-level attributes (e.g., interpersonal relationship, mutual trust/hostility, interdependence, and cooperation) and a better grasp of their pathology can add a crucial dimension to our understanding of mental health problems. A few recent studies have delved into the interpersonal behavioral processes in the context of different psychiatric abnormalities. Neuroimaging can supplement these approaches by providing insight into the neurobiology of interpersonal functioning. Keeping this view in mind, we discuss a recently developed approach in functional neuroimaging that calls for a shift from a focus on neural information contained within brain space to a multi-brain framework exploring degree of similarity/dissimilarity of neural signals between multiple interacting brains. We hypothesize novel applications of quantitative neuroimaging markers like inter-subject correlation that might be able to evaluate the role of interpersonal attributes affecting an individual or a group. Empirical evidences of the usage of these markers in understanding the neurobiology of social interactions are provided to argue for their application in future mental health research

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Not AvailableSince the dawn of human civilization humans have depended on a large number of crops which are now being reduced to few only. Due to this growing dependency on few and fewer crops diversity of our food basket is also deceasing. Millets are very nutritious and healthy food which is gradually losing its area to commercial crops. Instability analysis by coefficient of variation (CV) and instability index suggested by Cuddy and Della revealed that over the years production and productivity of both pearl millet and finger millet showed higher degree of variation. Compound annual growth rates (CAGR) indicated that over time production and productivity of pearl millet has increased despite decrease in area under cultivation. In case of finger millet area under cultivation and production has declined and productivity has increased.Not Availabl