Recovery of Global Symmetries in a 't Hooftian Universe

All fundamental Planck scale symmetries are restored on a global level when a new charge is postulated in a finite, closed, Euclidean discrete space. Gravity emerges as a residual effect of the electromagnetic force in this scenario, resulting in a deterministic toy universe driven by a single input parameter. The model is developed using a constructive approach. Randomness is identified using a Chaintin argument. Aleph0 definite value is tied to the size of the universe. This is not an interpretation of Quantum Mechanics, but a deeper attempt to describe nature.

Zeros of the isomonodromic tau functions in constructive conformal mapping of polycircular arc domains: the n-vertex case

The prevertices of the conformal map between a generic, n-vertex, simply connected, polycircular arc domain and the upper half plane are determined by finding the zeros of an isomonodromic tau function. The accessory parameters of the associated Fuchsian equation are then found in terms of logarithmic derivatives of this tau function. Using these theoretical results a constructive approach to the determination of the conformal map is given and the particular case of 5 vertices is considered in detail. A computer implementation of a construction of the isomonodromic tau function described by Gavrylenko & Lisovyy [Comm. Math. Phys., 363, 2018)] is used to calculate some illustrative examples. A procedural guide to constructing the conformal map to a given polycircular arc domain using the method presented here is also set out.

Informatics as a Fundamental Discipline in General Education: The Danish Perspective

Informatics in general, and the particular development of artificial intelligence, is changing human knowledge, perception, and reality, thus radically changing the course of human history. Informatics has made it possible to automate an extraordinary range of tasks by enabling machines to play an increasingly decisive role in drawing conclusions from data and then taking action. The growing transfer of judgment from human beings to machines denotes the revolutionary aspect of informatics.For societies to maintain or regain democratic control and supremacy over digital technology, it is imperative to include informatics in general education with a dual perspective on possibilities and implications of computing for individuals and society. The Danish informatics curriculum for general education acknowledges the dual and bipartite nature of informatics by complementing a constructive approach to computing with a critical analytic approach to digital artifacts.

Quantum error correction and holographic information from bilocal holography

Bilocal holography is a constructive approach to the higher spin theory holographically dual to O(N ) vector models. In contrast to other approaches to bulk reconstruction, bilocal holography does not take input from the dual gravitational theory. The resulting map is a complete bulk/boundary mapping in that it maps the complete set of O(N ) invariant degrees of freedom in the CFT, to the complete set of higher spin degrees of freedom. After restricting to a suitable code subspace we demonstrate that bilocal holography naturally reproduces the quantum error correcting properties of holography and it gives a robust bulk (entanglement wedge) reconstruction. A gauge invariant entangled pair of CFT degrees of freedom are naturally smeared over a semicircle in the bulk spacetime, which is highly suggestive of bit threads. Finally, we argue that finite N relations in the CFT, when interpreted in the dual AdS spacetime, can provide relations between degrees of freedom located near the boundary and degrees of freedom deep in the bulk.

Risks of water and wastewater PPP projects: an investors’ perspective

Purpose Water and wastewater (WW) projects are gaining attention in Iran because of shortages of water resources. However, these projects are lengthy and they are accompanied by numerous risks, such as lack of sufficient financial resources. Public–private partnerships (PPPs) are taken into account as a constructive approach to deal with the problem of insufficient government funds and they are increasingly being implemented to construct the required infrastructures in different countries. Although WW projects in PPPs can reduce the government’s debt, investors are still uncertain about this approach. Hence, this study aims to identify and evaluate the risk of all parties involved in WW-PPP projects, from the viewpoint of investor. Design/methodology/approach First, the risk factors which are involved in WW projects are identified by interviewing experts and reviewing the literature by means of fault tree analysis (FTA) tool. Second, the probability and effects of the risky factors which are related to specific event are evaluated and analyzed by hybridization of interval fuzzy Type-2 sets (IT2FS) and risk score formulation. Finally, some solutions are proposed to deal with the most challenging risks. Findings Six gate events, namely, risks which are related to investors such as investor’s consultant-related risks, risky conditions from engineering, procurement, and construction (EPC) contractors’ point of view, risk factors which public sector takes into account, public sector’s consultant-related risks which public sector’s consultant consider challenging and external factors were defined according to the literature. From FTA tool and by interviewing the experts, 94 basic events were identified. Finally, from hybridization of IT2FSs and risk score formulation, top five risks are determined as “Difficulty of injecting financial resources into the project,” “Fluctuation in inflation rate,” “Poor decision-making process” in public sector, “Difficulty of importing the equipment which are required for the project (such as pumps, grain catchers, garbage collectors, etc.) from other countries” and “Impact of risky conditions in other projects on operation of PPP project.” Originality/value In the absence of a constructive approach for risk identification and a reliable model for evaluating the identified risks in PPP projects, this research project is one of the first research studies which used FTA for identifying risks and hybridization of IT2FSs and risk score formulation for evaluating the risks.

THE METHODOLOGY TO SYSTEMATISE, PRESENT AND USE HISTORICAL CARTOGRAPHY: POTENTIALS AND LIMITS TO ANALYSE AND ENHANCE WIDESPREAD HISTORICAL CENTRES IN NORTHERN ITALY

Researchers from diverse fields of study are developing methodologies for understanding historical cartography. Nonetheless, there is a lack of literature that explains the connection between the survey and the interactive use of historical cartography in preservation projects and urban planning. This study demonstrates the methods for the investigation of historical cartography to produce knowledge about the heritage of small widespread historical centres in northern Italy, which had a rich history, and for which many thematic maps were produced through time. The complexity of the area gives a fertile ground to collect, systematise and investigate historical sources. The methodology is developed to be flexible and adaptable to various widespread historical centres in the territory and it is divided into two parts: deconstructive and constructive approach. Whereas the former deals with the analysis of urban aspects on historical maps, the latter searches for the historical elements present nowadays. Combining those two methods in the Geographic Information Systems will produce a timeline and historical stratification of the transformation of cities. Once georeferenced and vectorised, historical maps are enriched with the information from written registers and other historical documents, as well as contemporary ones. The study aims to scrutinize and produce various categories of maps, to draw conclusions about the limits of the use of historical cartography and software used, and finally, to suggest how and where the future work could lead to the overall enhancement of heritage.