As quantum information science approaches the goal of constructing quantum computers, understanding loss of information through decoherence becomes increasingly important. The information about a system that can be obtained from its environment can facilitate quantum control and error correction. Moreover, observers gain most of their information indirectly, by monitoring (primarily photon) environments of the “objects of interest.” Exactly how this information is inscribed in the environment is essential for the emergence of “the classical” from the quantum substrate. In this paper, (...) we examine how many-qubit (or many-spin) environments can store information about a single system. The information lost to the environment can be stored redundantly, or it can be encoded in entangled modes of the environment. We go on to show that randomly chosen states of the environment almost always encode the information so that an observer must capture a majority of the environment to deduce the system’s state. Conversely, in the states produced by a typical decoherence process, information about a particular observable of the system is stored redundantly. This selective proliferation of “the fittest information” (known as Quantum Darwinism) plays a key role in choosing the preferred, effectively classical observables of macroscopic systems. The developing appreciation that the environment functions not just as a garbage dump, but as a communication channel, is extending our understanding of the environment’s role in the quantum-classical transition beyond the traditional paradigm of decoherence. (shrink)

The following quotations describe in “nutshells” a few highlights of John Archibald Wheeler's contributions to physics. The contributions are arranged in roughly the following order: (i) concrete research results, (ii) innovative ideas that have become foundations for the research of others, (iii) insights that give guidance for the development of physics over the coming decades. Since most of Wheeler's work contains strong elements of two or even all three of these characteristics, the editors have not attempted to delineate the dividing (...) lines between the three categories. (shrink)

Early twelfth-century logicians invoked past-tensed statements with future-oriented contents to undermine the assumption that every proposition ‘about the past’ is determinate. In the second half of the century, the notion of future-dependence was used to restrict the scope of necessity per accidens. At some point, this idea began to be applied in theology to solve puzzles surrounding predestination, prescience, prophecy, and faith. In the mid-1160s, Magister Udo quotes some thinkers who insisted that the principle of the necessity of the past (...) should exclude dicta that ‘relate to the future’, such as that he has been predestined. Peter of Poitiers adopted this ‘Ockhamist’ strategy around 1170. We find similar accounts in Simon of Tournai and Alan of Lille, who invoked it in other contexts as well. By the time of Praepositinus of Cremona, Hubert of Pirovano, and Stephen Langton, the restricted principle became something of a common view at Paris. (shrink)

The World 3 theory outlined by Popper in the 1960s has been diversely received, raising enthusiasms as well as severe criticisms. In this paper, I resituate the theory in the development of Popper’s philosophy. I not only present the three “sources” of W3, but I also show that the first one dominates the two others. Comparing it with a few other evolutionary philosophies, I propose to understand Popper’s metaphysics as part of an evolutionary and spiritualist philosophy, which was, however, always (...) balanced by a strong ethical reminder of the inescapability of human responsibility. (shrink)

In this work, an intuitionistic propositional logic with a Galois connection is introduced. In addition to the intuitionistic logic axioms and inference rule of modus ponens, the logic contains only two rules of inference mimicking the performance of Galois connections. Both Kripke-style and algebraic semantics are presented for IntGC, and IntGC is proved to be complete with respect to both of these semantics. We show that IntGC has the finite model property and is decidable, but Glivenko's Theorem does not hold. (...) Duality between algebraic and Kripke semantics is presented, and a representation theorem for Heyting algebras with Galois connections is proved. In addition, an application to rough L-valued sets is presented. (shrink)

In Zielonka (1981a, 1989), I found an axiomatics for the product-free calculus L of Lambek whose only rule is the cut rule. Following Buszkowski (1987), we shall call such an axiomatics linear. It was proved that there is no finite axiomatics of that kind. In Lambek's original version of the calculus (cf. Lambek, 1958), sequent antecedents are non empty. By dropping this restriction, we obtain the variant L0 of L. This modification, introduced in the early 1980s (see, e.g., Buszkowski, 1985; (...) Zielonka, 1981b), did not gain much popularity initially; a more common use of L0 has only occurred within the last few years (cf. Roorda, 1991: 29). In Zielonka (1988), I established analogous results for the restriction of L0 to sequents without left (or, equivalently, right) division. Here, I present a similar (cut-rule) axiomatics for the whole of L0.This paper is an extended, corrected, and completed version of Zielonka (1997). Unlike in Zielonka (1997), the notion of rank of an axiom is introduced which, although inessential for the results given below, may be useful for the expected non-finite-axiomatizability proof.The paper follows the same way of subject exposition as Zielonka (2000) but it is technically much less complicated. I restrict myself to giving bare results; all the ideological background is exactly the same as in case of the non-associative calculusNL0 and those who are interested in it are requested to consult the introductory section of Zielonka (2000). (shrink)

This breakthrough volume integrates European, British, and American scholarship in advanced areas of philosophy and decision theory. Contributions cover a broad area of economics--from criticism of institutional economics to examination of the role of induction in economic forecasting.

In [4], I proved that the product-free fragment L of Lambek's syntactic calculus (cf. Lambek [2]) is not finitely axiomatizable if the only rule of inference admitted is Lambek's cut-rule. The proof (which is rather complicated and roundabout) was subsequently adapted by Kandulski [1] to the non-associative variant NL of L (cf. Lambek [3]). It turns out, however, that there exists an extremely simple method of non-finite-axiomatizability proofs which works uniformly for different subsystems of L (in particular, for NL). We (...) present it below to the use of those who refer to the results of [1] and [4]. (shrink)

In [2], Bar-Hillel, Gaifman, and Shamir prove that the simple phrase structure grammars dened by Chomsky are equivalent in a cer- tain sense to Bar-Hillel's bidirectional categorial grammars . On the other hand, Cohen [3] proves the equivalence of the latter ones to what he calls free categorial grammars . They are closely related to Lambek's syntactic calculus which is, in turn, based on the idea due to Ajdukiewicz [1]. For some reasons, Cohen's proof seems to be at least in- (...) complete. Here, I give a short outline of the direct proof of the equivalence between SF G's and F CG's. (shrink)

This paper addresses the notion of communicative action on the basis of Alfred Schutz’ writings. In Schutz’ work, communication is of particular significance and its importance is often neglected by phenomenologists. Communication plays a crucial role in his first major work, the Der sinnhafte Aufbau der sozialen Welt from 1932, yet communication is also a major feature in his unfinished works which were later completed posthumously by Thomas Luckmann: The Structures of the Life World (1973, 1989). In these texts, Schutz (...) sometimes refers to “communicative action,” and he comes to ascribe a crucial role to communication within the domain of the life world he calls everyday life. Based on Schutz’ texts, I shall first attempt to critically reconstruct the defining features of his notion of communication and communicative action. As a result, it emerges that Schutz’ notion of communication, particularly in its early incarnation, seems to be, at first glance, characterized by a dichotomy between virtual communication, that is communicative action in a narrow sense, and non-virtual communication. As I want to show with respect to the seemingly established dichotomous distinction between “mediated” and “immediate social action,” Schutz himself started to overcome this dichotomy. Based on this thesis, I will try to sketch a basic outline of a theory of communicative action, a theory less formulated by Schutz’ than built on Schutz’ writings. As the idea of communicative action, and particularly the transgression of the distinction between mediated and immediate action, affects the very structures of the life-world described by Schutz and Luckmann, I will ultimately demonstrate that any mundane phenomenology of the life-world requires a triangulatory method. (shrink)

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This essay attempts to define a value (not «the» value) of what, in it, comes to be called an «eccentric». In a largely standardized and stereotyped society like ours of the present times, a society where a human being can be creative but only within certain predefined limits, diverse groups exert all kinds of pressure on an individual, and with growing geographical as well as social mobility these kinds of pressure, intertwined and superimposed, give rise to overdue stress and situations (...) of psychological and maybe even metaphysical impossibility. One solution is a «no notice» attitude, in which all rules but a few selected ones are more or less dignifiedly flouted. Another solution is an attitude of an eccentric, close to, but not identical with, that of John Henry Newman’s «gentleman». I try to define this attitude and show one of its values: enabling us to evade too much social pressure without estranging us from society. (shrink)

First published in 2003. Routledge is an imprint of Taylor & Francis, an informa company.

Frühere Strafrechte definierten Zurechnungsfähigkeit mit Hilfe der Willensfreiheit; gegenwärtig dient eine "Fäigkeit, gemäß einer Einsicht zu handeln" diesem Zwecke, Aber beide Begriffe ermöglichen keine praktizierbare Unterscheidung zwischen normalen Tätern und solchen, die straffrei bleiben sollen. Eine solcheUnterscheidung ist nur unter dem Präventivstandpunkt möglich: Wer durch die üblichen Strafen nicht gebessert wird oder nicht gebessert werden muß (Schocktäter), soll diesen Strafen nicht unterworfen werden. Allenfalls muß er von der Gemeinschaft isoliert werden. Welcher Personenkreis hier in Frage kommt, kann nur empirisch festgestellt (...) werden. Empirisch ist auch die Frage, ob nicht aus Abschreckungsgründen auch unzurechnungsfähige Täter zu bestrafen sind. (shrink)