A Picard-S Iterative Scheme for Approximating Fixed Point of Weak-Contraction Mappings

We study the convergence analysis of a Picard-S iteration method for a particular class of weak-contraction mappings. Furthermore, we prove a data dependence result for fixed point of the class of weak-contraction mappings with the help of the Picard-S iteration methods

Regime change in the Aegean after the Second World War: Reconsidering the foreign influence

According to the conventional view held by the Greek sources, the United States was involved in the establishment of the 1967 Greek junta and helped sustain it. Similarly, the existing literature on the 1950 Turkish transition to democracy holds that one of the determinants of democratization was the desire to become part of the Western alliance. Thus, quite ironically, the new world order set out by the US at the end of the Second World War is seen as the cause of diametrically opposite regimes in two neighboring countries belonging to the same alliance. Whereas in Greece it is seen responsible from an authoritarian regime, in Turkey it is believed to be the cause of democracy.What was then the real effect of US foreign policy in Greek and Turkish regimes? In my paper, I will argue that the main dynamic behind these regimes was domestic, rather than international. In the Turkish case, the democratic regime was demanded by a group of elites, who had been threatened by the policies of the single party regime during the war. In the Greek case, the military staged a coup in order to prevent what it believed was a leftist threat coming from in fact a center party.However, a closer study of historical data reveals that the new world order played an indirect role in the establishment of the Greek and Turkish regimes. In the Turkish case, the collapse of the fascist regimes after the war and the Turkish foreign policy of allying with the West legitimized the demands and strengthened the hands of the Turkish elites who favored democracy. In the Greek case, the perception of communist threat, shared by the Western bloc, bred the exaggerated fear the colonels felt from the center party. In addition, American military aid during the Cold War increased the strength of the Greek armed forces relative to other forces in society. This power imbalance gave the colonels the capability to take over the government and suppress the opposing (and weaker) societal forces and elites. In conclusion, I argue that we must focus first on the domestic dynamics and then on the indirect role American foreign policy played after the Second World War. In this way, we are able to explain both the paradox the two Aegean countries provide and gain a new understanding of how foreign influence has affected Greece and Turkey after the war

Continuous Hawking-Page transitions in Einstein-scalar gravity

We investigate continuous Hawking-Page transitions in Einstein's gravity coupled to a scalar field with an arbitrary potential in the weak gravity limit. We show that this is only possible in a singular limit where the black-hole horizon marginally traps a curvature singularity. Depending on the subleading terms in the potential, a rich variety of continuous phase transitions arise. Our examples include second and higher order, including the Berezinskii-Kosterlitz-Thouless type. In the case when the scalar is dilaton, the condition for a continuous phase transition lead to (asymptotically) linear-dilaton background. We obtain the scaling laws of thermodynamic functions, as well as the viscosity coefficients near the transition. In the limit of weak gravitational interactions, the bulk viscosity asymptotes to a universal constant, independent of the details of the scalar potential. As a byproduct of our analysis we obtain a one-parameter family of kink solutions in arbitrary dimension d that interpolate between AdS near the boundary and linear-dilaton background in the deep interior. The continuous Hawking-Page transitions found here serve as holographic models for normal-to superfluid transitions.Comment: 35 pages + appendice

Holographic bulk viscosity: GPR vs EO

Recently Eling and Oz (EO) proposed a formula for the holographic bulk viscosity, in arXiv:1103.1657, derived from the null horizon focusing equation. This formula seems different from that obtained earlier by Gubser, Pufu and Rocha (GPR) in arXiv:0806.0407 calculated from the IR limit of the two-point function of the trace of the stress tensor. The two were shown to agree only for some simple scaling cases. We point out that the two formulae agree in two non-trivial holographic theories describing RG flows. The first is the strongly coupled N=2* gauge theory plasma. The second is the semi-phenomenological model of Improved Holographic QCD.Comment: 21 pages, 2 figure

Dynamical gauge fields and anomalous transport at strong coupling

Anomalous transport coefficients are known to be universal in the absence of dynamical gauge fields. We calculate the corrections to these universal values due to dynamical gluon fields at strong coupling, at finite temperature and finite density, using the holographic duality. We show that the consistent chiral magnetic and chiral vortical currents receive no corrections, while we derive a semi-analytic formula for the chiral separation conductivity. We determine these corrections in the large color, large flavor limit, in terms of a series expansion in the anomalous dimension $\Delta$ of the axial current in terms of physical parameters $\Delta$, temperature, electric and chiral chemical potentials and the flavor to color ratio $\frac{N_f}{N_c}$. Our results are applicable to a generic class of chiral gauge theories that allow for a holographic description in the gravity approximation. We also determine the dynamical gluon corrections to the chiral vortical separation current in a particular example in the absence of external axial fields.Comment: 28 pages + appendices, 3 figure

Implementation of a "Self-Sufficient Ageing" Policy and Possible Challenges: Case of Turkey

The policies of socioeconomic protection of older adults in most parts of the world are being redesigned in the scope of value-added targets, such as active ageing, successful ageing, or creative ageing. The main purpose here is, of course, enabling older adults self-sufficient and beneficial both for themselves and their social environment, instead of being simply the passive beneficiaries of the public support mechanisms. Turkey has a population which is still young but ageing very rapidly and will reach to the same point as Europe today in a relatively much shorter time. However, the country still seems to be away from conducting systematic and holistic measures, except for a few ineffective strategy papers and legal regulations. Therefore, Turkey must immediately design a new policy agenda in conformity with its traditional and historical advantages. Revitalizing the intergenerational solidarity bonds, in this regard, may be the best cost-effective solution to complement formal measures in the provision of social protection and in the process of active ageing. However, this traditional protection net is under attack of increasingly transforming socioeconomic conditions. Consequently, as one of the most rapidly ageing countries in the world, Turkey should immediately stimulate studies and debates over a healthy, functional, and effective ageing period and caring issues. Otherwise, governments will be blindsided by the socioeconomic, psychological, cultural, and physiological problems related to the ageing process. In the light of these facts, the main purpose of this study is to discuss policy recommendations to create a self-sufficient ageing period for older adults in the context of Turkish case

Strongly-coupled anisotropic gauge theories and holography

We initiate a non-perturbative study of anisotropic, non-conformal and confining gauge theories that are holographically realized in gravity by generic Einstein-Axion-Dilaton systems. In the vacuum our solutions describe RG flows from a conformal field theory in the UV to generic scaling solutions in the IR with generic hyperscaling violation and dynamical exponents $\theta$ and $z$. We formulate a generalization of the holographic c-theorem to the anisotropic case. At finite temperature, we discover that the anisotropic deformation reduces the confinement-deconfinement phase transition temperature suggesting a possible alternative explanation of inverse magnetic catalysis solely based on anisotropy. We also study transport and diffusion properties in anisotropic theories and observe in particular that the butterfly velocity that characterizes both diffusion and growth of chaos transverse to the anisotropic direction, saturates a constant value in the IR which can exceed the bound given by the conformal value.Comment: 6 pages, 4 figures; v2: minor improvements, references added, version accepted for publication in PR