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Architettura e memoria della Shoah: l’opera di Peter Eisenman a Berlino
Get PDFRIASSUNTO Nel maggio 2005 è stato inaugurato a Berlino il “Memoriale agli Ebrei d’Europa uccisi” su progetto di Peter Eisenman. La controversa vicenda dell’opera cominciò nel 1988 con l’idea lanciata dalla giornalista Lea Rosh di dedicare uno spazio alla memoria della Shoah nella capitale tedesca ed è passata attraverso due concorsi, fino ad approdare al progetto noto come “Eisenman II”: in una vasta area posta tra la Behrenstrasse e la Ebertstrasse (nei pressi della Porta di Brandeburgo) sono collocate, secondo una rigida griglia ortogonale, 2.711 stele di calcestruzzo speciale di una altezza variabile tra i 20 cm e gli oltre 4 m, che danno al visitatore l’idea di una immensa campagna modellata dal vento. Assolutamente privo di nomi e di significati simbolici che rimandino alla tradizione ebraica, il luogo vuole essere, nell’idea dell’architetto, uno spazio nel quale l’individuo è solo con se stesso e la sua mente, in modo da lasciar posto al ricordo. Ad una generica funzione evocativa del complesso, suggerita a chi ne percorre i sentieri, è affiancata la testimonianza concreta della documentazione storica esposta in un centro informazioni sotterraneo. Nella ripetizione della forma e nella estensione del memoriale si evoca il principio fondante dei drammi del Ventesimo secolo: la ragione che diventa follia se messa al servizio di progetti e ideali negativi, fino ad investire le vite e la storia umana in una vastità sconfinata di eventi di morte. SUMMARY In May 2005 was inaugurated in Berlin the "Memorial to the murdered Jews of Europe". The history of the Memorial began in 1988, when Germans decided to devote space to the memory of the Shoah in their capital. The competition for the monument was won by Peter Eisenman. In a very large space between the Behrenstrasse and Ebertstrasse (near the Brandenburg Gate) are located, according to a rigid orthogonal grid, 2711 stelae of a special concrete. Their height is variable between 20 cm and over 4 m, giving visitors the idea of a huge campaign shaped by the wind. Eisenman thought to an area in which the individual is alone with himself and his mind, to give place to remembrance. The generic evocative complex, receives a precise historical meaning thanks to the exhibition exposed in a subterranean information center. In the repetition of the form and the extent of the memorial, Eisenman wanted to evoke the founding principle of all the tragedies of the Twentieth century: the reason that becomes madness if put to serve negative projects and ideals, causing an infinite vastness of events of death
‘Everybody to count for one, nobody for more than one’: The principle of equal consideration of interests from Bentham to Pigou
No full textSUMMARY In chapter 5 of Utilitarianism, John Stuart Mill argued that the principle of utility ‘is a mere form of words without rational signification, unless one person’s happiness, supposed equal in degree [...], is counted for exactly as much as another’s. Those conditions being supplied, Bentham’s dictum, “everybody to count for one, nobody for more than one’” might be written under the principle of utility as an explanatory commentary’. The principle implied in this statement, often emancipated from its hedonistic attributes, is the principle of impartiality, or ‘the principle of equal consideration of interests’. This paper explores the meaning and implications of this principle by studying its changing definitions from Bentham to Pigou. Such a delimitation reveals two features of the present analysis: first, it examines a question that was at the crossroads between moral philosophy and economics; and second, it considers a period in which utilitarian ethics and marginalist economics were strictly based on hedonistic and cardinalistic assumptions. In this context, the question of how to weigh the happiness of different individuals was crucial for any application of utilitarian ethics, since the distribution of happiness and the distribution of the means of happiness are strictly related
Minimization Algorithm for Symbolic Bisimilarity
No full textThe operational semantics of interactive systems is usually decsribed by labeled transition systems. Abstract semantics is defined in terms of bisimilarity, that in the finite case, can be computed via the well-known partition refinement algorithm. However, the behavoiur of interactive systems is in many case infinite and thus checking bisimilarity in this way is unfeasible. Symbolic semantics allows to define smaller, possibly finite, transition systems, by employing symbolic actions and avoiding some source of infiniteness. Unfortunately, the standard partition refinement algorithm does not work with symbolic bisimilarity. In a previous paper, we have introduced an abstract theory of symbolic semantics. In this paper, we introduce a partition refinement algorithm for symbolic bisimilarity
Nodal quasiparticles and the onset of spin density wave order in the cuprates
No full textWe present a theory for the onset of spin density wave order in the
superconducting ground state of the cuprates. We compute the scaling dimensions
of allowed perturbations of a `relativistic' fixed point with O(4)xO(3)
symmetry, including those associated with the fermionic nodal Bogoliubov
quasiparticles. Analyses of up to six loops show that all perturbations with
square lattice symmetry are likely irrelevant. We demonstrate that the fermion
spectral functions are primarily damped by the coupling to fluctuations of a
composite field with Ising nematic order. We also discuss the influence of
quenched disorder
A Formal Analysis of Complex Type Flaw Attacks on Security Protocols.
No full textA simple type confusion attack occurs in a security protocol, when
a principal interprets data of one type as data of another. These
attacks can be successfully prevented by tagging types of each
field of a message. Complex type confusions occur instead when
tags can be confused with data and when fields or sub-segments of
fields may be confused with concatenations of fields of other
types. Capturing these kinds of confusions is not easy in a
process calculus setting, where it is generally assumed that
messages are correctly interpreted. In this paper, we model in the
process calculus LySa only the misinterpretation due to the
confusion of a concatenation of fields with a single field, by
extending the notation of one-to-one variable binding to
multi-to-one binding. We further present a formal way of detecting
these possible misinterpretations, based on a Control Flow
Analysis for this version of the calculus. The analysis
over-approximates all the possible behaviour of a protocol,
including those effected by these type confusions. As an example,
we considered the amended Needham-Schroeder symmetric protocol,
where we succeed in detecting the type confusion that lead to a
complex type flaw attacks it is subject to.
Therefore, the analysis can capture potential type confusions of this kind on
security protocols, besides other security properties such as
confidentiality, freshness and message authentication
Outer Approximation Algorithms for Canonical DC Problems
No full textThe paper discusses a general framework for outer approximation type algorithms for the canonical DC optimization problem. The algorithms rely on a polar reformulation of the problem and exploit an approximated oracle in order to check global optimality. Consequently, approximate optimality conditions are introduced and bounds on the quality of the approximate global optimal solution are obtained. A thorough analysis of properties which guarantee convergence is carried out; two families of conditions are introduced which lead to design six implementable algorithms, whose convergence can be proved within a unified framework
Replication vs Erasure Coding in Data Centric Storage for Sensor Networks
No full textIn-network storage of data in wireless
sensor networks (such as DCS-GHT, for instance) is considered a
viable alternative to external storage since it contributes to reduce
the communications inside the network and to favor data
aggregation. In current approaches it exploits pure data
replication to assure data availability. In this paper, we
consider the use of codes and data dispersal in
combination to in-network storage. In particular, given an abstract
model of in-network storage we show how codes can
be employed, and we discuss how this can be achieved in three cases
of study. Since the configuration of the
network is particularly critical with respect to correct data
encoding, we define framework aimed at evaluating the probability of
correct data encoding and decoding. Then we exploit this result and
simulations to show how, in the cases of study, the parameters of the
codes and the network should be configured in order
to achieve correct data coding and decoding with high probability
Multicritical Nishimori point in the phase diagram of the +- J Ising model on a square lattice
No full textWe investigate the critical behavior of the random-bond +- J Ising model on a
square lattice at the multicritical Nishimori point in the T-p phase diagram,
where T is the temperature and p is the disorder parameter (p=1 corresponds to
the pure Ising model). We perform a finite-size scaling analysis of
high-statistics Monte Carlo simulations along the Nishimori line defined by
, along which the multicritical point lies. The
multicritical Nishimori point is located at p^*=0.89081(7), T^*=0.9528(4), and
the renormalization-group dimensions of the operators that control the
multicritical behavior are y_1=0.655(15) and y_2 = 0.250(2); they correspond to
the thermal exponent \nu= 1/y_2=4.00(3) and to the crossover exponent \phi=
y_1/y_2=2.62(6)
Poverty, Population, Development in Historical Perspective
No full textSUMMARY The object of the paper is to place the present issues of world poverty, development, demographic change into proper historical perspective, considering the specificities of present times concerning economic and demographic developments, as well as the international relations associated with them. Some speculations concerning possible long run developments conclude the pape RIASSUNTO Scopo dell' articolo è di porre in adeguata prospettiva storica le questioni globali relative a povertà, sviluppo e crescita demografica, considerando le specifiche circostanze del tempo presente concernenti gli sviluppi economici e demografici, così come le relazioni internazionali a questi associati. Alcune considerazioni sui possibili sviluppi futuri di lungo periodo concludono il lavoro
Estimating The Size Of Peer-To-Peer Networks Using Lambert’s W Function
No full textSUMMARY In this work, we address the problem of locally estimating the size of a Peer-to-Peer (P2P) network using local information. We present a novel approach for estimating the size of a peer-to-peer (P2P) network, fitting the sum of new neighbors discovered at each iteration of a breadth-first search (BFS) with a logarithmic function, and then using Lambert’s W function to solve a root of a ln(n) + b − n = 0, where n is the network size. With rather little computation, we reach an estimation error of at most 10 percent, only allowing the BFS to iterate to the third level