Geometry of fully coordinated, two-dimensional percolation

We study the geometry of the critical clusters in fully coordinated percolation on the square lattice. By Monte Carlo simulations (static exponents) and normal mode analysis (dynamic exponents), we find that this problem is in the same universality class with ordinary percolation statically but not so dynamically. We show that there are large differences in the number and distribution of the interior sites between the two problems which may account for the different dynamic nature.Comment: ReVTeX, 5 pages, 6 figure

Re-evaluating Turkey’s global relationships and its shift toward the South-East Asian region

Turkey is strategically positioned at the crossroads of Europe, Asia, and Africa, and is considered an important geopolitical actor in the global arena. Since Turkey embraced neoliberal economic policies in the 1980s, it has emerged as one of the leading emerging economies with major trade links with the US, Russia, EU, and Asia. Turkey has been a longstanding member of the NATO alliance and signed the European Customs Union Agreement in 1995. With the advent of Asia as the global economic powerhouse, Turkey’s foreign and economic policy horizons today extend to the Asia-Pacific Region. Turkey plays a key role in China’s Belt and Road Initiative and with the launching of the Asia Anew Initiative in late 2019, Ankara has redoubled efforts to forge closer ties with the ten members of the Association of Southeast Asian Nations (ASEAN) and with ASEAN itself. This paper will explore and evaluate Turkey’s foreign policy over the last two decades and the shift from the principle of Strategic Depth to that of Strategic Autonomy. The article will also review Turkey’s current change in international orientation and its international re-orientation toward Asia

Growth Law and Superuniversality in the Coarsening of Disordered Ferromagnets

We present comprehensive numerical results for domain growth in the two-dimensional {\it Random Bond Ising Model} (RBIM) with nonconserved Glauber kinetics. We characterize the evolution via the {\it domain growth law}, and two-time quantities like the {\it autocorrelation function} and {\it autoresponse function}. Our results clearly establish that the growth law shows a crossover from a pre-asymptotic regime with "power-law growth with a disorder-dependent exponent" to an asymptotic regime with "logarithmic growth". We compare this behavior with previous results on one-dimensional disordered systems and we propose a unifying picture in a renormalization group framework. We also study the corresponding crossover in the scaling functions for the two-time quantities. Super-universality is found not to hold. Clear evidence supporting the dimensionality dependence of the scaling exponent of the autoresponse function is obtained.Comment: Thoroughly revised manuscript. The Introduction, Section 2 and Section 4 have been largely rewritten. References added. Final version accepted for publication on Journal of Statistical Mechanics: Theory and Experimen

Signatures of charmonium modification in spatial correlation functions

We study spatial correlation functions of charmonium in 2+1 flavor QCD using an improved staggered formulation. Contrary to the temporal correlation functions the spatial correlation functions exhibit a strong temperature dependence above the QCD transition temperature. Above this temperature they are sensitive to temporal boundary conditions. Both features become significant at a temperature close to 1.5 Tc and suggest corresponding modifications of charmonium spectral functions.Comment: 12 pages, LaTeX, 3 figure

Does Increasing Product Complexity and Diversity Cause Economic Growth in the Long-Run? A GMM Panel VAR Evidence

Using aggregate data from 31 Organization for Economic Co-operation and Development (OECD) countries covering periods from 1982 to 2017, this study examines the notion that the level of product complexity is a good determinant of economic growth in the long run. We use the impulse-response function (IRF) computed from the consistent generalized method of moment panel vector autoregressive (GMM pVAR) model to estimate the response of the real output growth to a change in the economic complexity index. The IRF shows that the economic complexity index has a significant impact on economic growth; a 1 standard deviation shock to the economic complexity index at time 0 contributes around 2.34 percentage points to the average rate of growth of output within the first period. The point estimates are positive and significant up to the third period. The cumulative IRF shows that the aggregate impact on economic growth is about 4.4% in the long run. Compared to some widely used innovation proxies such as the gross expenditure on research and development and secondary school enrollment, the economic complexity index performs relatively better in our model in determining economic growth in the long run

Manifestation of helical edge states as zero-bias magneto-tunneling-conductance peaks in non-centrosymmetric superconductors

Helical edge states exist in the mixed spin-singlet and -triplet phase of a noncentrosymmetric superconductor (NCSS) when the pair amplitude (PA) in the negative helicity band, $\Delta_-$, is smaller than the PA in the positive helicity band, $\Delta_+$, i.e., when the PA in the triplet component is more than the same in the singlet component. We numerically determine energies of these edge states as a function of $\gamma = \Delta_-/\Delta_+$. The presence of these edge states is reflected in the tunneling process from a normal metal to an NCSS across a bias energy $eV$: (i) Angle resolved spin conductance (SC) obeying the symmetry $g_s(\phi) =-g_s(-\phi)$ shows peaks when the bias energy equals the available quasiparticle edge state energy provided $|eV| \lesssim \Delta_-$. (ii) The total SC, $G_s$, is zero but modulates with $eV$ for finite magnetic field $H$. (iii) The zero bias peaks of $G_s$ and total charge conductance, $G_c$, at finite $H$ split into two at finite $eV$ for moderate $H$. (iv) At zero bias, $G_c$ and $G_s$ increase with $H$ and show peaks at $|H|\sim \gamma H_0$ where $H_0$ is a characteristic field.Comment: minor changes; one figure is adde

Empirical Analysis of an Augmented Schumpeterian Endogenous Growth Model

This study conducts an empirical analysis of an augmented Schumpeterian endogenous growth theory using aggregate-level data from 1981 to 2017 for 31 OECD countries. Despite a considerable number of studies analysing endogenous growth, cross-country analyses utilising estimators robust to endogeneity-bias and controlling for the macroeconomic effect of institutions are still rare. In this paper, we employ a relatively consistent estimator to analyse an augmented neoclassical production function that links output per worker to capital accumulation, technological progress, and institutions. Our results from the extended system of generalised method of momentS estimation align with the mainstream consensus that capital accumulation and technological progress or innovation, in the form of R&D activities, determine the level of output per worker in the long run. But in addition, we find that effective institutions underlie the innovation effect. On average, the impact of R&D activities on output per worker is higher in countries with more effective institutions