Rethinking the Idea of Ability: Convergence of People, Paradigms and Prototypes

This research article explores the evolving concept of ability in the context of contemporary society, focusing on the convergence of diverse elements such as individuals, paradigms, and prototypes. The traditional understanding of ability has often been confined to predefined norms and standardized measures. However, societal shifts, technological advancements, and a growing awareness of diversity have prompted a reevaluation of this notion. This article delves into the multidimensional nature of ability and examines how it is shaped by the interplay of people, paradigms, and prototypes. The article addresses challenges and opportunities associated with this evolving paradigm, providing insights into workplace dynamics, innovation, and the promotion of diversity and inclusivity. Discussions extend to implications and future directions, considering the intersection of technological advancements and human augmentation. In conclusion, the article emphasizes the necessity for ongoing research and exploration in the dynamic landscape of ability, advocating for a holistic understanding that captures the complexities of contemporary societ

Supernovae Rates: A Cosmic History

We discuss the cosmic history of supernovae on the basis of various assumptions and recent data on the star formation history. We show that supernova rates as a function of redshift can be used to place significant constraints on progenitor models, on the star formation history, and on the importance of dust obscuration. We demonstrate that it is unlikely that the current observational indications for the existence of a cosmological constant are merely an artifact of the dominance of different progenitor classes at different redshift intervals.Comment: Accepted for publication in The Astrophysical Journa

The Role of Technology in Elevating Financial Performance: A Study of Afghan Commercial Banking

This research embarks on a comprehensive journey to uncover how online banking fundamentally shapes the financial landscape and stability of commercial banks in Afghanistan. With a focal point on the inaugural commercial bank established in the region, the study seeks to delve into the discernible and quantifiable impacts of online banking on the intricate financial operations of these institutions. The specific aim is to meticulously measure and understand the exact influence of online banking on the financial performance of commercial banks in Afghanistan. Anticipated findings from this research endeavor hold the promise of providing crucial insights into the pivotal role that digital banking plays in sculpting the financial trajectory of the Afghan banking sector. Through a rigorous and thorough examination of the effects of online banking, this study aspires to generate invaluable knowledge beneficial not only for industry practitioners but also for policymakers operating within the financial realm. These insights possess the potential to guide strategic decisions and navigate the course of financial practices within the Afghan banking landscape, ultimately fostering a more robust and resilient financial sector

How to determine an effective potential for a variable cosmological term

It is shown that if a variable cosmological term in the present Universe is described by a scalar field with minimal coupling to gravity and with some phenomenological self-interaction potential $V(\varphi)$, then this potential can be unambiguously determined from the following observational data: either from the behaviour of density perturbations in dustlike matter component as a function of redshift (given the Hubble constant additionally), or from the luminosity distance as a function of redshift (given the present density of dustlike matter in terms of the critical one).Comment: Latex, 7 pages, JETP Lett., in press, 199

The Age-Redshift Relation for Standard Cosmology

We present compact, analytic expressions for the age-redshift relation $\tau(z)$ for standard Friedmann-Lema\^ \itre-Robertson-Walker (FLRW) cosmology. The new expressions are given in terms of incomplete Legendre elliptic integrals and evaluate much faster than by direct numerical integration.Comment: 13 pages, 3 figure

Cosmological Constraints from the ROSAT Deep Cluster Survey

The ROSAT Deep Cluster Survey (RDCS) has provided a new large deep sample of X-ray selected galaxy clusters. Observables such as the flux number counts n(S), the redshift distribution n(z) and the X-ray luminosity function (XLF) over a large redshift baseline (z\lesssim 0.8) are used here in order to constrain cosmological models. Our analysis is based on the Press-Schechter approach, whose reliability is tested against N-body simulations. Following a phenomenological approach, no assumption is made a priori on the relation between cluster masses and observed X-ray luminosities. As a first step, we use the local XLF from RDCS, along with the high-luminosity extension provided by the XLF from the BCS, in order to constrain the amplitude of the power spectrum, \sigma_8, and the shape of the local luminosity-temperature relation. We obtain \sigma_8=0.58 +/- 0.06 for Omega_0=1 for open models at 90% confidence level, almost independent of the L-T shape. The density parameter \Omega_0 and the evolution of the L-T relation are constrained by the RDCS XLF at z>0 and the EMSS XLF at z=0.33, and by the RDCS n(S) and n(z) distributions. By modelling the evolution for the amplitude of the L-T relation as (1+z)^A, an \Omega_0=1 model can be accommodated for the evolution of the XLF with 1<A<3 at 90% confidence level, while \Omega_0=0.4^{+0.3}_{-0.2} and \Omega_0<0.6 are implied by a non--evolving L-T for open and flat models, respectively.Comment: 12 pages, 9 colour figures, LateX, uses apj.sty, ApJ, in press, May 20 issu

Improvements in the M-T relation and mass function and the measured Omega_m through clusters evolution

In this paper, I revisit the constraints obtained by several authors (Reichart et al. 1999; Eke et al. 1998; Henry 2000) on the estimated values of Omega_m, n and sigma_8 in the light of recent theoretical developments: 1) new theoretical mass functions (Sheth & Tormen 1999, Sheth, Mo & Tormen 1999, Del Popolo 2002b); 2) a more accurate mass-temperature relation, also determined for arbitrary Omega_m and Omega_{\Lambda} (Voit 2000, Pierpaoli et al. 2001, Del Popolo 2002a). Firstly, using the quoted improvements, I re-derive an expression for the X-ray Luminosity Function (XLF), similarly to Reichart et al. (1999), and then I get some constraints to \Omega_m and n, by using the ROSAT BCS and EMSS samples and maximum-likelihood analysis. Then I re-derive the X-ray Temperature Function (XTF), similarly to Henry (2000) and Eke et al. (1999), re-obtaining the constraints on Omega_m, n, sigma_8. Both in the case of the XLF and XTF, the changes in the mass function and M-T relation produces an increase in Omega_m of \simeq 20% and similar results in sigma_8 and n.Comment: 34 pages, 11 encapsulated figures. Accepted by Ap

The evolution of clusters in the CLEF cosmological simulation: X-ray structural and scaling properties

We present results from a study of the X-ray cluster population that forms within the CLEF cosmological hydrodynamics simulation, a large N-body/SPH simulation of the Lambda CDM cosmology with radiative cooling, star formation and feedback. The scaled projected temperature and entropy profiles at z=0 are in good agreement with recent high-quality observations of cool core clusters, suggesting that the simulation grossly follows the processes that structure the intracluster medium (ICM) in these objects. Cool cores are a ubiquitous phenomenon in the simulation at low and high redshift, regardless of a cluster's dynamical state. This is at odds with the observations and so suggests there is still a heating mechanism missing from the simulation. Using a simple, observable measure of the concentration of the ICM, which correlates with the apparent mass deposition rate in the cluster core, we find a large dispersion within regular clusters at low redshift, but this diminishes at higher redshift, where strong "cooling-flow" systems are absent in our simulation. Consequently, our results predict that the normalisation and scatter of the luminosity-temperature relation should decrease with redshift; if such behaviour turns out to be a correct representation of X-ray cluster evolution, it will have significant consequences for the number of clusters found at high redshift in X-ray flux-limited surveys.Comment: 20 pages, 21 figures, MNRAS, accepted with minor modifications to original manuscrip