883 research outputs found
Regression and the Maternal in the History of Psychoanalysis, 1900-1957
This paper examines the history of the concept of ‘regression’ as it was perceived by Sandor Ferenczi and some of his followers in the first half of the twentieth century. The first part provides a short history of the notion of ‘regression’ from the late nineteenth century to Ferenczi's work in the 1920s and 1930s. The second and third parts of the paper focus on two other thinkers on regression, who worked in Britain, under the influence of the Ferenczian paradigm – the interwar Scottish psychiatrist, Ian D. Suttie; and the British-Hungarian psychoanalyst, and Ferenczi's most important pupil, Michael Balint. Rather than a descriptive term which comes to designate a pathological mental stage, Ferenczi understood ‘regression’ as a much more literal phenomenon. For him, the mental desire to go backwards in time is a universal one, and a consequence of an inevitable traumatic separation from the mother in early childhood, which has some deep personal and cultural implications. The paper aims to show some close affinities between the preoccupation of some psychoanalysts with ‘regression’, and the growing interest in social and cultural aspects of ‘motherhood’ and ‘the maternal role’ in mid-twentieth-century British society
A Characterization of Infinite LSP Words
G. Fici proved that a finite word has a minimal suffix automaton if and only
if all its left special factors occur as prefixes. He called LSP all finite and
infinite words having this latter property. We characterize here infinite LSP
words in terms of -adicity. More precisely we provide a finite set of
morphisms and an automaton such that an infinite word is LSP if
and only if it is -adic and all its directive words are recognizable by
Interpolator symmetries and new Kalton-Peck spaces
Diagrams generated by three interpolators in an abstract Kalton-Montgomery
complex like interpolation scheme. We will consider in detail the case of the
first three Schechter interpolators associated to the usual Calder\'on complex
interpolation method in two especially interesting cases: weighted
spaces, i.e., interpolation pairs , and
spaces, i.e., the interpolation pair ,
both at
Symmetries in Quantum Key Distribution and the Connection between Optimal Attacks and Optimal Cloning
We investigate the connection between the optimal collective eavesdropping
attack and the optimal cloning attack where the eavesdropper employs an optimal
cloner to attack the quantum key distribution (QKD) protocol. The analysis is
done in the context of the security proof in [Devetak and Winter, Proc. of the
Roy. Soc. of London Series A, 461, 207 (2005); Kraus, Gisin and Renner, Phys.
Rev. Lett. 95, 080501 (2005)] for discrete variable protocols in d-dimensional
Hilbert spaces. We consider a scenario in which the protocols and cloners are
equipped with symmetries. These symmetries are used to define a quantum cloning
scenario. We find that, in general, it does not hold that the optimal attack is
an optimal cloner. However, there are classes of protocols, where we can
identify an optimal attack by an optimal cloner. We analyze protocols with 2, d
and d+1 mutually unbiased bases where d is a prime, and show that for the
protocols with 2 and d+1 MUBs the optimal attack is an optimal cloner, but for
the protocols with d MUBs, it is not. Finally, we give criteria to identify
protocols which have different signal states, but the same optimal attack.
Using these criteria, we present qubit protocols which have the same optimal
attack as the BB84 protocol or the 6-state protocol
Structure of K-interval exchange transformations: Induction, trajectories, and distance theorems
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