10,632 research outputs found
"Rare" Fluctuation Effects in the Anderson Model of Localization
We discuss the role of rare fluctuation effects in quantum condensed matter
systems. In particular, we present recent numerical results of the effect of
resonant states in Anderson's original model of electron localization. We find
that such resonances give rise to anomalous behavior of eigenstates not just
far in the Lifshitz tail, but rather for a substantial fraction of eigenstates,
especially for intermediate disorder. The anomalous behavior includes
non-analyticity in various properties as a characteristic. The effect of
dimensionality on the singularity, which is present in all dimensions, is
described, and the behavior for bounded and unbounded disorder is contrasted
Singular Behavior of Eigenstates in Anderson's Model of Localization
We observe a singularity in the electronic properties of the Anderson Model
of Localization with bounded diagonal disorder, which is clearly distinct from
the well-established mobility edge (localization-delocalization transition)
that occurs in dimensions . We present results of numerical calculations
for Anderson's original (box) distribution of onsite disorder in dimensions
= 1, 2 and 3. To establish this hitherto unreported behavior, and to understand
its evolution with disorder, we contrast the behavior of two different measures
of the localization length of the electronic wavefunctions - the averaged
inverse participation ratio and the Lyapunov exponent. Our data suggest that
Anderson's model exhibits richer behavior than has been established so far.Comment: Correction to v1: Fig.3 caption now displaye
Beurling algebra analogues of the classical theorems of Wiener and Levy on absolutely convergent Fourier series
Let be a continuous function on the unit circle , whose Fourier
series is -absolutely convergent for some weight on the set of
integers . If is nowhere vanishing on , then there
exists a weight on such that had -absolutely
convergent Fourier series. This includes Wiener's classical theorem. As a
corollary, it follows that if is holomorphic on a neighbourhood of the
range of , then there exists a weight on such that
\hbox{} has -absolutely convergent Fourier series. This is a
weighted analogue of L\'{e}vy's generalization of Wiener's theorem. In the
theorems, and are non-constant if and only if is
non-constant. In general, the results fail if or is required to be
the same weight .Comment: 4 page
The Augustan Principate and the Emergence of Biopolitics: A Comparative Historical Perspective
This paper uses Foucault’s concepts “discipline” and “biopower” to expose the complexity of power relations in Augustan Rome and its historiography. Focusing on Augustus’ Res Gestae and Tacitus’ Annales, I argue that the absolute sovereignty of the emperor did not preclude the advancement of techniques to classify, hierarchize and normalize individuals, nor did Imperial sovereignty work against the development of a discourse about the enhancement and protection of the population. By demonstrating the conceptual and historical relevancy of Foucault’s modern power triad of “sovereignty-discipline-government” to first century CE Rome, the paper suggests that biopolitical societies have a far more extensive history than the one said to have started around the turn of the eighteenth century
An interactive tool for real time feedback on diagnosis and treatment plan of arthritis based on C++ programing language
Arthritis causes joint inflammation where body’s immunity against disease or injury becomes overactive leading to swelling, pain and stiffness and it also can lead to tissue damage. Anatomically, arthritis usually affects the synovial joints in majority where the articular bones are covered by hyaline cartilages. The clinically significant arthritis are Osteoarthritis, Rheumatoid Arthritis, Septic arthritis and Juvenile Arthritis which features pain in the joints and typically worsen with age. Since the clinical burden due to arthritis is huge and due to the difficulties in proper differentiation and diagnosis of a particular arthritis, the examiner should determine the nature of the underlying pathologic process. Arthritis can be infectious (infection with Neisseria gonorrhea or Mycobacterium tuberculosis), crystal-induced (gout, pseudo-gout), immune-related [rheumatoid arthritis (RA), systemic lupus erythematous (SLE)], reactive (rheumatic fever, Reiter's syndrome), or idiopathic. Current project imposes the use of C++ programming language in order to construct an interactive platform for the diagnosis and treatment of Arthritis. Huge amount of work has been done on various diseases to design a platform where on the basis of symptoms, diseases can be treated promptly; however, in the field of arthritis, study is lacking. Briefly, an algorithm was prepared for classifying the types of arthritis based upon the symptoms and signs as obtained from the patient
Understanding the effectiveness of government interventions against the resurgence of COVID-19 in Europe
As European governments face resurging waves of COVID-19, non-pharmaceutical interventions (NPIs) continue to be the primary tool for infection control. However, updated estimates of their relative effectiveness have been absent for Europe’s second wave, largely due to a lack of collated data that considers the increased subnational variation and diversity of NPIs. We collect the largest dataset of NPI implementation dates in Europe, spanning 114 subnational areas in 7 countries, with a systematic categorisation of interventions tailored to the second wave. Using a hierarchical Bayesian transmission model, we estimate the effectiveness of 17 NPIs from local case and death data. We manually validate the data, address limitations in modelling from previous studies, and extensively test the robustness of our estimates. The combined effect of all NPIs was smaller relative to estimates from the first half of 2020, indicating the strong influence of safety measures and individual protective behaviours--such as distancing--that persisted after the first wave. Closing specific businesses was highly effective. Gathering restrictions were highly effective but only for the strictest limits. We find smaller effects for closing educational institutions compared to the first wave, suggesting that safer operation of schools was possible with a set of stringent safety measures including testing and tracing, preventing mixing, and smaller classes. These results underscore that effectiveness estimates from the early stage of an epidemic are measured relative to pre-pandemic behaviour. Updated estimates are required to inform policy in an ongoing pandemic
'Criminals' Performing for Change: Budhan Theatre´s fight against injustice and police atrocity
This is the final version of the article. Available from the publisher via the link in this record.This article is about the Budhan Theatre, located in Ahmedabad, Gujarat, India and known for using Street Theatre as a medium to bring about social change. Budhan’s street theatre is a new kind of theatre which brings individuals from the stigmatized community to the stage and aims to raise consciousness and demand social acceptance for them in the process. The article examines Budhan Theatre as a movement that brings about socio-political change in India and discusses its performances and their implications in light of performance studies. The discussion presented here is based on my observations, interviews with members of Budhan theatre, and print media coverage. I have been connected to Budhan theatre for the past five years through conducting this research, facilitating some of the children's workshops, talking to Chhara community members, and observing the group and their activities closely. The strategy of Budhan Theatre, which underlies each of its plays, is to highlight social problems by expressing people’s situations. The ideology and propaganda behind the performances are quite similar to those of other indigenous theatres in the world: to make the audience feel culpable about the plight of the oppressed by presenting their victimhood. The theatre company performs these plays throughout India and supports and fights for other denotified and nomadic tribes who are facing similar problems
Fast preparation of critical ground states using superluminal fronts
We propose a spatio-temporal quench protocol that allows for the fast
preparation of ground states of gapless models with Lorentz invariance.
Assuming the system initially resides in the ground state of a corresponding
massive model, we show that a superluminally-moving `front' that
quenches the mass, leaves behind it (in space) a state
to the ground state of the gapless model.
Importantly, our protocol takes time to produce
the ground state of a system of size ( spatial dimensions), while
a fully adiabatic protocol requires time
to produce a state with exponential accuracy in . The physics of the
dynamical problem can be understood in terms of relativistic rarefaction of
excitations generated by the mass front. We provide proof-of-concept by solving
the proposed quench exactly for a system of free bosons in arbitrary
dimensions, and for free fermions in . We discuss the role of
interactions and UV effects on the free-theory idealization, before numerically
illustrating the usefulness of the approach via simulations on the quantum
Heisenberg spin-chain.Comment: 4.25 + 10 pages, 3 + 2 figure
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