Perturbative reduction of derivative order in EFT

Higher derivative corrections are ubiquitous in effective field theories, which seemingly introduces new degrees of freedom at successive order. This is actually an artefact of the implicit local derivative expansion defining effective field theories. We argue that higher derivative corrections that introduce additional degrees of freedom should be removed and their effects captured either by lower derivative corrections, or special combinations of higher derivative corrections not propagating extra derees of freedom. Three methods adapted for this task are examined and field redefinitions are found to be most appropriate. First order higher derivative corrections in a scalar tensor theory are removed by field redefinition and it is found that their effects are captured by a subset of Horndeski theories. A case is made for restricting the effective field theory expansions in principle to only terms not introducing additional degrees of freedom.Comment: 45 page

Coordination Failures, Poverty Traps, "Big Push" Policy and Entrepreneurship: A Critical View

Poverty traps occurs when agents fail to coordinate their actions to achieve the optimal allocation of resources. It is argued that this phenomenon makes economic convergence impossible and keeps agents in a poverty trap from which they cannot escape unless a massive and coordinated industrial policy is implemented. This analysis shows that the literature on coordination failures has overemphasized the significance of market failure. It argues that coordination is possible and profitable in a free market system. State intervention is responsible for the systematic misallocation of resources (discoordination), in general, and for poverty traps in particular.coordination failure, poverty trap, industrial policy, market system

Coordination Failures, Cluster Theory and Entrepreneurship: A Critical View

Development policy has been energized in the last decades by a number of contributions emphasizing a new positive role the state can and should play in fostering economic growth. The central pillar of this literature is Michael Porter and his theory of clusters. A number of economists have attempted to anchor the appetite for clustering initiatives in a solid theoretical bedrock. They have pointed out an interesting market failure that may prevent the emergence of profitable clusters and thus jeopardize overall economic development: the failure of individuals to coordinate changes in their actions in order to reap the benefits of a better situation. This paper intends to provide a refutation of the idea that coordination failures as manifested in the inability of clusters to emerge can serve as a ground for government intervention. It uses mainly Porter, Rodrik and Rodriguez-Clare thesis as an example of this approach and criticizes the claim that coordination externalities prevent the market process to allocate resources optimally.Coordination, Market failure, Economic development

Coordination Failures, Cluster Theory and Entrepreneurship: A Critical View

Development policy has been energized in the last decades by a number of contributions emphasizing a new positive role the state can and should play in fostering economic growth. The central pillar of this literature is Michael Porter and his theory of clusters. This paper intends to provide a refutation of the idea that coordination failures as manifested in the inability of clusters to emerge can serve as a ground for government intervention. It uses mainly Porter, Rodrik and Rodriguez-Clare thesis as an example of this approach and criticizes the claim that coordination externalities prevent the market process to allocate resources optimallycoordination failure, cluster theory, development economics

Einstein-Gauss-Bonnet gravity in 4-dimensional space-time

In this Letter we present a general covariant modified theory of gravity in $D\!=\!4$ space-time dimensions which propagates only the massless graviton and bypasses the Lovelock's theorem. The theory we present is formulated in $D\!>\!4$ dimensions and its action consists of the Einstein-Hilbert term with a cosmological constant, and the Gauss-Bonnet term multiplied by a factor $1/(D\!-\!4)$. The four-dimensional theory is defined as the limit $D\!\to\!4$. In this singular limit the Gauss-Bonnet invariant gives rise to non-trivial contributions to gravitational dynamics, while preserving the number of graviton degrees of freedom and being free from Ostrogradsky instability. We report several appealing new predictions of this theory, including the corrections to the dispersion relation of cosmological tensor and scalar modes, singularity resolution for spherically symmetric solutions, and others.Comment: 6 pages, 1 figure; v3 accepted manuscrip

Understanding Process Performance Measurement Systems

The purpose of this paper is to analyze the current state of Process Performance Measurement Systems (PPMS) by means of a systematic review of literature. The PPMS literature is reviewed using a systematic approach. Based on an extensive literature review only twelve articles that contain the term PPMS in the title were found. The literature analysis showed that PPMS is a relatively new topic in the area of performance measurement. In order to understand PPMS, it was crucial to explain the concepts of business process management, business performance measurement and Performance Measurement System (PMS) which are well known and used in the literature and practice. PPMS is a special type of PMS that should be used in process-oriented organizations. Limitations of this research lie in the fact that all the conclusions were derived only from the literature, not empirical research. The results presented in the paper continue towards providing an updated overview of the current state of performance measurement, especially PPMS in order to identify the existing research gaps on which ongoing and future research efforts regarding this topic can be focused.business process management; process orientation; performance indicators; business performance measurement; Performance Measurement System; Process Performance Measurement System

Romania in the European Union: political integration vs.economic integration

Although highly beneficial from a pragmatic point of view, Romania’s accession in the European Union is problematic, especially in the long run and from a theoretical perspective. In the short run, adoption of european model emphasizes the advantages of economic integration. In the long run however, political considerations can dominate economic liberties.European Union, political integration, economic integration, economic liberties

Inflation from cosmological constant and nonminimally coupled scalar

We consider inflation in a universe with a positive cosmological constant and a nonminimally coupled scalar field, in which the field couples both quadratically and quartically to the Ricci scalar. When considered in the Einstein frame and when the nonminimal couplings are negative, the field starts in slow roll and inflation ends with an asymptotic value of the principal slow roll parameter, $\epsilon_E=4/3$. Graceful exit can be achieved by suitably (tightly) coupling the scalar field to matter, such that at late time the total energy density reaches the scaling of matter, $\epsilon_E=\epsilon_m$. Quite generically the model produces a red spectrum of scalar cosmological perturbations and a small amount of gravitational radiation. With a suitable choice of the nonminimal couplings, the spectral slope can be as large as $n_s\simeq 0.955$, which is about one standard deviation away from the central value measured by the Planck satellite. The model can be ruled out by future measurements if any of the following is observed: (a) the spectral index of scalar perturbations is $n_s>0.960$; (b) the amplitude of tensor perturbations is above about $r\sim 10^{-2}$; (c) the running of the spectral index of scalar perturbations is positive.Comment: 19 pages, 13 figure