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Author(s):  
Adam Koons ◽  
Jennifer Trivedi

Disaster Anthropology uses theoretical and methodological tools from across anthropological subfields to understand the effects of disasters. Anthropologists based in academia and practice, often working collaboratively or across disciplines, seek to understand the relationships among historical, social, cultural, economic, political, environmental, and climatic factors in every type of disaster and humanitarian crisis across the globe. Practitioners often work within disaster response agencies in such functions as policy reform, program design, and disaster response management. Academics work in anthropology and interdisciplinary centers and departments, studying and teaching about disaster and anthropological issues. Disaster anthropologists link closely with broader interdisciplinary disaster studies and practices. They contribute an anthropological, holistic, and long-term perspective, including the use of ethnography and participant observation, theories, and analyses. In the early 21st century there has been considerable, and constantly increasing, recognition of disaster anthropology. This area of work includes recognition of what disaster anthropology has to contribute and its place as an appropriate field of engagement for anthropologists. This recognition has been demonstrated by the publication of numerous books, chapters, articles, special journal issues, and hundreds of conference presentations. Disaster anthropology has gained the support of the major anthropology associations such as the American Anthropological Association (AAA) and the Society for Applied Anthropology (SfAA), resulting in the formation of specialized formalized bodies such as the Risk and Disaster Topical Interest Group (RDTIG) within the SfAA, and the Culture and Disaster Network (CADAN). Accordingly, there are also an increasing number of targeted university anthropology courses on disasters. Disaster anthropologists contribute to the overall understanding of how and why disasters have the impacts that they do and what the consequences of disasters can be. By examining disaster contexts, disaster anthropologists improve understanding of pre-existing circumstances that contribute to those disasters, including people’s perspectives on hazards, risks, uncertainty, inequality, and inequity. Disaster anthropologists have shown that disasters are the visible, explicit result of deeper and more complex processes. Anthropologists share this work in governmental, nongovernmental, academic, and public arenas. Disaster anthropology brings together critical lines of inquiry from the larger fields of anthropology and disaster studies, offering valuable perspectives not only on understanding but also on improving disaster conditions.



Author(s):  
S. Lueddeckens ◽  
P. Saling ◽  
E. Guenther

AbstractAlthough the weighting of environmental impacts against each other is well established in life cycle assessment practice, the weighting of impacts occurring at different points in time is still controversial. This temporal weighting is also known as discounting, which due to its potential to offend principles of intergenerational equity, is often rejected or regarded as unethical. In our literature review, we found multiple disputes regarding the comprehension of discounting. We structured those controversial issues and compared them to the original discounted utility model on which discounting is based. We explain the original theory as an intertemporal decision instrument based on future utility. We conclude that intertemporal equity controversies can be solved if discounting is applied as an individual decision instrument, rather than as an information instrument, which could underestimate environmental damages handed to future generations. Each choice related to discounting—including whether or not to discount, or to discount at a rate of zero—should be well-founded. We illustrate environmental decision-related problems as a multidimensional issue, with at least three dimensions including the type of impact and spatial and temporal distributions. Through discounting framed as a decision instrument, these dimensions can be condensed into an explicit result, from which we can draw analogies to both weighting in life cycle assessment and financial decision instruments. We suggest avoiding discounting in environmental information instruments, such as single-product life cycle assessments, footprints, or labels. However, if alternatives have to be compared, discounting should be applied to support intertemporal decisions and generate meaningful results.



2021 ◽  
Vol 27 (3) ◽  
Author(s):  
Pierrick Bousseau

AbstractWe show that, after the change of variables $$q=e^{iu}$$ q = e iu , refined floor diagrams for $${\mathbb {P}}^2$$ P 2 and Hirzebruch surfaces compute generating series of higher genus relative Gromov–Witten invariants with insertion of a lambda class. The proof uses an inductive application of the degeneration formula in relative Gromov–Witten theory and an explicit result in relative Gromov–Witten theory of $${\mathbb {P}}^1$$ P 1 . Combining this result with the similar looking refined tropical correspondence theorem for log Gromov–Witten invariants, we obtain a non-trivial relation between relative and log Gromov–Witten invariants for $${\mathbb {P}}^2$$ P 2 and Hirzebruch surfaces. We also prove that the Block–Göttsche invariants of $${\mathbb {F}}_0$$ F 0 and $${\mathbb {F}}_2$$ F 2 are related by the Abramovich–Bertram formula.



Author(s):  
Wai Kiu Chan ◽  
Haochen Gao ◽  
Han Li


2020 ◽  
Vol 2020 (9) ◽  
Author(s):  
Guido Festuccia ◽  
Anastasios Gorantis ◽  
Antonio Pittelli ◽  
Konstantina Polydorou ◽  
Lorenzo Ruggeri

Abstract We construct a large class of gauge theories with extended supersymmetry on four-dimensional manifolds with a Killing vector field and isolated fixed points. We extend previous results limited to super Yang-Mills theory to general $$ \mathcal{N} $$ N = 2 gauge theories including hypermultiplets. We present a general framework encompassing equivariant Donaldson-Witten theory and Pestun’s theory on S4 as two particular cases. This is achieved by expressing fields in cohomological variables, whose features are dictated by supersymmetry and require a generalized notion of self-duality for two-forms and of chirality for spinors. Finally, we implement localization techniques to compute the exact partition function of the cohomological theories we built up and write the explicit result for manifolds with diverse topologies.



2020 ◽  
Vol 80 (7) ◽  
Author(s):  
Mirko Serino

Abstract We present an explicit momentum space computation of the four-point function of the energy-momentum tensor in 4 spacetime dimensions for the free and conformally invariant theory of a scalar field. The result is obtained by explicit evaluation of the Feynman diagrams by tensor reduction. We work by embedding the scalar field theory in a gravitational background consistently with conformal invariance in order to derive all the terms the correlator consists of and all the Ward identities implied by the requirements of general covariance and anomalous Weyl symmetry. We test all these identities numerically in several kinematic configurations. Mathematica notebooks detailing the step-by-step computation are made publicly available through a GitHub repository (https://github.com/mirkos86/4-EMT-correlation-function-in-a-4d-CFT.). To the best of our knowledge, this is the first explicit result for the four-point correlation function of the energy-momentum tensor in a conformal and non supersymmetric field theory which is readily numerically evaluable in any kinematic configuration.



Mathematics ◽  
2018 ◽  
Vol 6 (8) ◽  
pp. 135 ◽  
Author(s):  
Alexander Van-Brunt ◽  
Matt Visser

The Baker–Campbell–Hausdorff (BCH) expansion is a general purpose tool of use in many branches of mathematics and theoretical physics. Only in some special cases can the expansion be evaluated in closed form. In an earlier article we demonstrated that whenever [X,Y]=uX+vY+cI, BCH expansion reduces to the tractable closed-form expression Z(X,Y)=ln(eXeY)=X+Y+f(u,v)[X,Y], where f(u,v)=f(v,u) is explicitly given by the the function f(u,v)=(u−v)eu+v−(ueu−vev)uv(eu−ev)=(u−v)−(ue−v−ve−u)uv(e−v−e−u). This result is much more general than those usually presented for either the Heisenberg commutator, [P,Q]=−iℏI, or the creation-destruction commutator, [a,a†]=I. In the current article, we provide an explicit and pedagogical exposition and further generalize and extend this result, primarily by relaxing the input assumptions. Under suitable conditions, to be discussed more fully in the text, and taking LAB=[A,B] as usual, we obtain the explicit result ln(eXeY)=X+Y+Ie−LX−e+LYI−e−LXLX+I−e+LYLY[X,Y]. We then indicate some potential applications.



2017 ◽  
Vol 14 (01) ◽  
pp. 255-288
Author(s):  
Evan Chen ◽  
Peter S. Park ◽  
Ashvin A. Swaminathan

Let [Formula: see text] and [Formula: see text] be [Formula: see text]-nonisogenous, semistable elliptic curves over [Formula: see text], having respective conductors [Formula: see text] and [Formula: see text] and both without complex multiplication. For each prime [Formula: see text], denote by [Formula: see text] the trace of Frobenius. Assuming the Generalized Riemann Hypothesis (GRH) for the convolved symmetric power [Formula: see text]-functions [Formula: see text] where [Formula: see text], we prove an explicit result that can be stated succinctly as follows: there exists a prime [Formula: see text] such that [Formula: see text] and [Formula: see text] This improves and makes explicit a result of Bucur and Kedlaya. Now, if [Formula: see text] is a subinterval with Sato–Tate measure [Formula: see text] and if the symmetric power [Formula: see text]-functions [Formula: see text] are functorial and satisfy GRH for all [Formula: see text], we employ similar techniques to prove an explicit result that can be stated succinctly as follows: there exists a prime [Formula: see text] such that [Formula: see text] and [Formula: see text]



2016 ◽  
Vol 55 (2) ◽  
pp. 177-197 ◽  
Author(s):  
Adrian W. Dudek
Keyword(s):  


2015 ◽  
Vol 53 (1) ◽  
pp. 23-29
Author(s):  
Adrian W. Dudek
Keyword(s):  


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