729 research outputs found
Pre-Visions: Firts results of the EDEN Fellows survey on the futures of learning
Technology is pervasive and intertwined in many aspects of modern life and society. The digital revolution that is
sweeping the world has shown its potential in education during the Covid-19 pandemic. It is rapidly transforming
the way students learn, and as a result, technology is expected to improve the face of education by making it
more inclusive and accessible. In the framework of the EDEN Pre-Visions project, the EDEN fellows conducted a
prospective study on the future trends of open and digital education in Europe in the next decade. 40 EDEN
Fellows took part in an online survey launched in January 2023. In this paper, we present and analyse the first
results of this exercise, describing the views of the experts on six dimensions: the European context evolution
and socio-economic dynamics; EdTech research and development; EdTech practices; institutional digital
transformation; societal impacts and implications; policies and regulations.info:eu-repo/semantics/publishedVersio
Computing Blackhole Partition Functions from Quasinormal Modes
We propose a method of computing one-loop determinants in black hole space-times (with emphasis on asymptotically anti-de Sitter black holes) that may be used for numerics when completely-analytic results are unattainable. The method utilizes the expression for one-loop determinants in terms of quasinormal frequencies determined by Denef, Hartnoll and Sachdev in [1]. A numerical evaluation must face the fact that the sum over the quasinormal modes, indexed by momentum and overtone numbers, is divergent. A necessary ingredient is then a regularization scheme to handle the divergent contributions of individual fixed-momentum sectors to the partition function. To this end, we formulate an effective two-dimensional problem in which a natural refinement of standard heat kernel techniques can be used to account for contributions to the partition function at fixed momentum. We test our method in a concrete case by reproducing the scalar one-loop determinant in the BTZ black hole background. We then discuss the application of such techniques to more complicated spacetimes
Can the Arts Change the World? The Transformative Power of the Arts in Fostering and Sustaining Social Change
A group of nonprofit leaders working in the arts, advocacy, political organizing, social services, and education explored the connection between community organizing and creative expression by engaging in collective activities, including visiting various examples of community arts, and experimentation with their own practice. Through this process, the group concluded that arts could be socially transformative; that community arts can create a safe space that allows people to trust and be open to changing; that art can help people reflect together and not talk past one another; and that the process of creating together can be healing and sustaining
Real-time finite-temperature correlators from AdS/CFT
In this paper we use AdS/CFT ideas in conjunction with insights from finite
temperature real-time field theory formalism to compute 3-point correlators of
super Yang-Mills operators, in real time and at finite
temperature. To this end, we propose that the gravity field action is
integrated only over the right and left quadrants of the Penrose diagram of the
Anti de Sitter-Schwarzschild background, with a relative sign between the two
terms. For concreteness we consider the case of a scalar field in the black
hole background. Using the scalar field Schwinger-Keldysh bulk-to-boundary
propagators, we give the general expression of a 3-point real-time Green's
correlator. We then note that this particular prescription amounts to adapting
the finite-temperature analog of Veltman's circling rules to tree-level Witten
diagrams, and comment on the retarded and Feynman scalar bulk-to-boundary
propagators. We subject our prescription to several checks: KMS identities, the
largest time equation and the zero-temperature limit. When specializing to a
particular retarded (causal) 3-point function, we find a very simple answer:
the momentum-space correlator is given by three causal (two retarded and one
advanced) bulk-to-boundary propagators, meeting at a vertex point which is
integrated from spatial infinity to the horizon only. This result is expected
based on analyticity, since the retarded n-point functions are obtained by
analytic continuation from the imaginary time Green's function, and based on
causality considerations.Comment: 43 pages, 6 figures Typos fixed, reference added, one set of plots
update
A review of a carbonaceous chondrite: what can we learn from the Kaba meteorite?
The Tenth Symposium on Polar Science/Poster presentations: [OA] Antarctic meteorites, Wed. 4 Dec. / Entrance Hall (1st floor), National Institute of Polar Researc
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