Heisenberg, in constructing quantum mechanics, explicitly followed certain principles exemplified, as he believed, in Einstein's construction of the special theory of relativity which for him was the paradigm for radical theoretic change in physics. These were the principles of scientific realism, stability of background knowledge, E-observability, contextual re-interpretation, pragmatic continuity, model continuity, simplicity. Fifty years later, in retrospect, Heisenberg added the following two: a principle of non-proliferation of competing theories - scientific revolutions are not a legitimate goal of physics - (...) and a principle of tenacity - existing theories are to be conserved as far as possible. The conservative as well as the revolutionary potential of these principles is then discussed. A more penetrating philosophical criticism of these principles is postponed. (shrink)

v. 1. Atomic theory and the description of nature -- v. 2. Essays 1932-1957 on atomic physics and human knowledge -- v. 3. Essays 1958-1962 on atomic physics and human knowledge -- v. 4. Causality and complementarity.

In contrast to the theories of relativity, quantum mechanics is not yet based on a generally accepted conceptual foundation. It is proposed here that the missing principle may be identified through the observation that all knowledge in physics has to be expressed in propositions and that therefore the most elementary system represents the truth value of one proposition, i.e., it carries just one bit of information. Therefore an elementary system can only give a definite result in one specific measurement. The (...) irreducible randomness in other measurements is then a necessary consequence. For composite systems entanglement results if all possible information is exhausted in specifying joint properties of the constituents. (shrink)

Foundational investigations in quantum mechanics, both experimental and theoretical, gave birth to the field of quantum information science. Nevertheless, the foundations of quantum mechanics themselves remain hotly debated in the scientific community, and no consensus on essential questions has been reached. Here, we present the results of a poll carried out among 33 participants of a conference on the foundations of quantum mechanics. The participants completed a questionnaire containing 16 multiple-choice questions probing opinions on quantum-foundational issues. Participants included physicists, philosophers, (...) and mathematicians. We describe our findings, identify commonly held views, and determine strong, medium, and weak correlations between the answers. Our study provides a unique snapshot of current views in the field of quantum foundations, as well as an analysis of the relationships between these views. (shrink)

Die von Jens Timmermann besorgte Neuausgabe innerhalb der Philosophischen Bibliothek bietet den vollständigen Wortlaut der beiden Originalausgaben von 1781 und 1787. Der Kantische Text wurde unter Wahrung der Interpunktion und sprachlicher Eigenheiten sehr behutsam an die heutigen orthographischen Regeln angeglichen. Die semantisch bedeutenden Korrekturvorschläge späterer Herausgeber (nicht nur der Akademie-Ausgabe) sind, wo sie nicht in den Text Aufnahme gefunden haben, am Fuß der Seite verzeichnet. Alle wesentlichen Unterschiede zwischen den Originalausgaben sind durch Kursivdruck hervorgehoben, größere Abweichungen ganzer Textstücke - etwa (...) in der Einleitung und im Kapitel über Phaenomena und Noumena - wurden synoptisch gegenübergestellt, so daß Art und Umfang der Umarbeitung unmittelbar abgelesen werden können. Die durchgängig neu bearbeitete Studienausgabe folgt in den Grundprinzipien der seit 1926 in Forschung und Lehre maßgeblichen Ausgabe von Raymund Schmidt, die hiermit abgelöst wird. Sie wird ergänzt durch eine umfangreiche Bibliographie von Heiner Klemme sowie durch einen ausführlichen Personen- und Sachindex. (shrink)

Thomas S. Kuhn's classic book is now available with a new index.

Entanglement was initially thought by some to be an oddity restricted to the realm of thought experiments. However, Bell’s inequality delimiting local - behavior and the experimental demonstration of its violation more than 25 years ago made it entirely clear that non-local properties of pure quantum states are more than an intellectual curiosity. Entanglement and non-locality are now understood to figure prominently in the microphysical world, a realm into which technology is rapidly hurtling. Information theory is also increasingly recognized by (...) physicists and philosophers as intimately related to the foundations of mechanics. The clearest indicator of this relationship is that between quantum information and entanglement. To some degree, a deep relationship between information and mechanics in the quantum context was already there to be seen upon the introduction by Max Born and Wolfgang Pauli of the idea that the essence of pure quantum states lies in their provision of probabilities regarding the behavior of quantum systems, via what has come to be known as the Born rule. The significance of the relationship between mechanics and information became even clearer with Leo Szilard’s analysis of James Clerk Maxwell’s infamous demon thought experiment. Here, in addition to examining both entanglement and quantum information and their relationship, I endeavor to critically assess the influence of the study of these subjects on the interpretation of quantum theory. (shrink)