This book celebrates the work of Giancarlo Ghiradi.

Bohmian Mechanics was formulated in 1952 by David Bohm as a complete theory of quantum phenomena based on a particle picture. It was promoted some decades later by John S. Bell, who, intrigued by the manifestly nonlocal structure of the theory, was led to his famous Bell's inequalities. Experimental tests of the inequalities verified that nature is indeed nonlocal. Bohmian mechanics has since then prospered as the straightforward completion of quantum mechanics. This book provides a systematic introduction to Bohmian mechanics (...) and to the mathematical abstractions of quantum mechanics, which range from the self-adjointness of the Schrödinger operator to scattering theory. It explains how the quantum formalism emerges when Boltzmann's ideas about statistical mechanics are applied to Bohmian mechanics. The book is self-contained, mathematically rigorous and an ideal starting point for a fundamental approach to quantum mechanics. It will appeal to students and newcomers to the field, as well as to established scientists seeking a clear exposition of the theory. (shrink)

A source of much difficulty and confusion in the interpretation of quantum mechanics is a naive realism about operators. By this we refer to various ways of taking too seriously the notion of operator-as-observable, and in particular to the all too casual talk about measuring operators that occurs when the subject is quantum mechanics. Without a specification of what should be meant by measuring a quantum observable, such an expression can have no clear meaning. A definite specification is provided by (...) Bohmian mechanics, a theory that emerges from Schrödinger's equation for a system of particles when we merely insist that particles means particles. Bohmian mechanics clarifies the status and the role of operators as observables in quantum mechanics by providing the operational details absent from standard quantum mechanics. It thereby allows us to readily dismiss all the radical claims traditionally enveloping the transition from the classical to the quantum realm — for example, that we must abandon classical logic or classical probability. The moral is rather simple: Beware naive realism, especially about operators! (shrink)

Segundo as descobertas da Física Moderna (Física Quántica), Realidade (Wirklichkeit em Alemão) não é mais o real que nos é familiar e tangível (cousal), mas algo bem diferente, tanto espacial como temporalmente, algo claramente mais aberto. Trata-se de algo holístico, uma Gestalt de carácter a-material, uma relação depura inter-conexão ("a-dvaita"), uma potencialidade inseparável, similar ao amor espiritual e omnicompreensivo. Ou seja, segundo o autor, a realidade está possuída por uma tonalidade processual, uma inspiração holística e intimamente conectada, uma transformação, um (...) processo contínuo de criação e aniquilamento, com o potencial de se manifestar a si mesma de um modo em que predomina uma essencial complementaridade dual energético-material. Assim, para o autor do artigo, o mundo em que vivemos, Wirklichkeit, não pode ser propriamente compreendido em termos puramente ontológicos. Segundo o autor, a questão : O que é, o que é que existe? torna-se uma questão desprovida de sentido. Em sua opinião, admissíveis seriam apenas questões acerca do que propriamente actua (wirkt), do que acontece, do que conecta, ou, por outras palavras, a questão do "entre". Consequentemente, a evolução no tempo e no espaço não procede mais de leis causais estritamente determinadas, pois o que existe são apenas tendências gerais intrínsecas (expectações), caracterizadas por probabilidades relativas a uma infinidade de realizações possíveis, as quais em média, pelo processo de sobreposições descoerentes, nos fazem voltar à nossa concepção comum do mundo como sendo uma realidade tangível dominada por leis naturais rigorosa e universalmente válidas. /// According to the findings of modern physics (quantum physics) Reality (in German more appropriate: Wirklichkeitj is basically no more the familiar, tangible (thing-like) reality but quite different and, spatially and temporally, more open. It is a holistic a-material "Gestalt", a pure connectedness ("a-dvaita"), an inseparable potentiality, similar to the spiritual and to all-embracing love. It relates to a processlike holistic and intimately connected inspiration and transformation, a continuous creation and annihilation, with the potential manifesting itself with some vagueness in complementary dual and essentially energetic/material diversified fashion. Hence, for the author, the world in which we are living, Wirklichkeit, cannot be understood strictly in an ontological way. The question: What is, what exists? becomes meaningless. Questions still admissible are: What acts (wirkt), happens, binds?, the question for the "in-between". The evolution in time does not follow anymore from strictly determined causal laws but there are only general intrinsic tendencies ("expectations"), characterised by probabilities for infinitely many possible realizations, which on average (decoherent superpositions) lead back to our familiar conception of the world as an objective tangible reality with its rigorously valid natural laws. (shrink)

Bohmian mechanics is a theory about point particles moving along trajectories. It has the property that in a world governed by Bohmian mechanics, observers see the same statistics for experimental results as predicted by quantum mechanics. Bohmian mechanics thus provides an explanation of quantum mechanics. Moreover, the Bohmian trajectories are defined in a non-conspiratorial way by a few simple laws.

This article deals with the notion of jurisdictional discourse, which, as a specific type of complex discourse, always poses a real challenge to translators. The authors present a contrastive analysis of the texts of legal decisions in French, German and Polish in order to demonstrate the difficulties in translation and the consequences which they entail, and to suggest a strategy for overcoming them. Firstly, the authors briefly compare the texts of judicial decisions indicating their characteristics both in terms of the (...) macrostructure of the text and in terms of syntactic and lexical units. Secondly, they explain the origin of the difficulties in translation resulting from the qualitative differences of the legal systems. Thirdly, the different types of difficulties are described and illustrated by practical examples, in order to make experienced translators and apprentice translators sensitive to them. The corpus used for the analysis consists of the integral and documented texts of the French, German and Polish judgments rendered in matters of civil law [37]. It should also be noted that the analyzed texts are comparable texts, which are a valuable tool for translators and allow them to acquire means of expression that are as natural as possible [40]. Regarding the methodology, the authors adopt for the analysis the contrastive method, borrowed from the theory of cultural transfer [15]. (shrink)

Quantum philosophy, a peculiar twentieth-century malady, is responsible for most of the conceptual muddle plaguing the foundations of quantum physics. When this philosophy is eschewed, one naturally arrives at Bohmian mechanics, which is what emerges from Schrodinger's equation for a nonrelativistic system of particles when we merely insist that 'particles' means particles. While distinctly non-Newtonian, Bohmian mechanics is a fully deterministic theory of particles in motion, a motion choreographed by the wave function. The quantum formalism emerges when measurement situations are (...) analyzed according to this theory. When the quantum formalism is regarded as arising in this way, the paradoxes and perplexities so often associated with quantum theory simply evaporate.Bohr's ... approach to atomic problems ... is really remarkable. He is completely convinced that any understanding in the usual sense of the word is impossible. Therefore the conversation is almost immediately driven into philosophical questions, and soon you no longer know whether you really take the position he is attacking, or whether you really must attack the position he is defending. (shrink)

J. Phys. A, to appear, quant-ph/0506173.

It is well known that density matrices can be used in quantum mechanics to represent the information available to an observer about either a system with a random wave function (“statistical mixture”) or a system that is entangled with another system (“reduced density matrix”). We point out another role, previously unnoticed in the literature, that a density matrix can play: it can be the “conditional density matrix,” conditional on the configuration of the environment. A precise definition can be given in (...) the context of Bohmian mechanics, whereas orthodox quantum mechanics is too vague to allow a sharp definition, except perhaps in special cases. In contrast to statistical and reduced density matrices, forming the conditional density matrix involves no averaging. In Bohmian mechanics with spin, the conditional density matrix replaces the notion of conditional wave function, as the object with the same dynamical significance as the wave function of a Bohmian system. (shrink)

In this review, we will focus on the role played by transcription factors of the E2F/DP family in controlling the expression of genes that carry out important cell‐cycle control functions, thereby ensuring ordered progression through the mammalian cell division cycle. The emerging picture is that cell‐cycle progression depends on the execution of a regulatory cascade of gene expression, driven by E2F/DP transcription factors, which are in turn regulated by the products of some of these genes. That E2F factors are potent (...) regulators of cell‐cycle checkpoints in mammalian cells is supported by experiments demonstrating that ectopic expression of individual E2F family members is sufficient to modulate cell proliferation and apoptosis. It is also clear that deregulation of E2F activity will result in the loss of particular checkpoint controls, thereby predisposing cells to malignant conversion. BioEssays 21:221–230. 1999. © 1999 John Wiley & Sons, Inc. -/- . (shrink)

We analyze the origin of quantum randomness within the framework of a completely deterministic theory of particle motion—Bohmian mechanics. We show that a universe governed by this mechanics evolves in such a way as to give rise to the appearance of randomness, with empirical distributions in agreement with the predictions of the quantum formalism. Crucial ingredients in our analysis are the concept of the effective wave function of a subsystem and that of a random system. The latter is a notion (...) of interest in its own right and is relevant to any discussion of the role of probability in a deterministic universe. (shrink)

Human encroachment on the habitats of wild animals and the dense living conditions of farmed animals increase spill-over risk of emerging infectious diseases from animals to humans (such as COVID-19). In this article, we defend two claims: First, we argue that in order to limit the risk of emerging infectious disease outbreaks in the future, a One Health approach is needed, which focuses on human, animal, and environmental health. Second, we claim that One Health should not solely be grounded in (...) collaborations between veterinary, medical, and environmental scientists, but should also involve more dialogue with animal and environmental ethicists. Such an interdisciplinary approach would result in epidemiology-driven measures that are ethically legitimate. (shrink)

We critically examine the role and status probabilities, as they enter via the Quantum Equilibrium Hypothesis, play in the standard, deterministic interpretation of deBroglie’s and Bohm’s Pilot Wave Theory (dBBT), by considering interpretations of probabilities in terms of ignorance, typicality and Humean Best Systems, respectively. We argue that there is an inherent conflict between dBBT and probabilities, thus construed. The conflict originates in dBBT’s deterministic nature, rooted in the Guidance Equation. Inquiring into the latter’s role within dBBT, we find it (...) explanatorily redundant (in particular for dBBT’s solution of the Measurement Problem, which only requires that the corpuscles possess definite positions), and subject to a number of difficulties. Following a suggestion from Bell, we propose to abandon the Guidance Equation, whilst retaining dBBT’s point particle-based Primitive Ontology, with positions as local beables. The resultant theory, which we identify as a stochastic, minimally deBroglie-Bohmian theory, describes a random walk through configuration space. Its probabilities, we propose, are best understood as dispositions of possible corpuscle configurations to manifest themselves. We subsequently evaluate the merits of sdBBT vis-à-vis dBBT, such as the justification of the Symmetrisation Postulate and the violation of the Action-Reaction Principle. Not only is sdBBT an attractive Bohmian theory that, whilst retaining dBBT's virtues, overcomes many of its shortcomings; it also sparks off a number of exciting follow-up questions, such as a comparison between sdBBT and other stochastic hidden-variable theories, e.g. Nelson Stochastics, or between sdBBT and the Everett interpretation. (shrink)

In classical physics, the world is considered as a matter-based reality, the arrangement of whose parts in time is uniquely determined by certain dynamic laws. By contrast, modern quantum physics reveals that matter is not composed of matter, but reality is merely potentiality. The world has a holistic structure, which is based on fundamental relations and not material objects, admitting more open, indeterministic developments. In this more flexible causal framework, inanimate and animate matter are not to be considered as fundamentally (...) different but as different order structures of the same immaterial entity. In a stable configuration, effectively all the uncertainties are statistically averaged out, thus the unique and deterministic behavior of ordinary inanimate matter is exhibited; whereas in the case of statically unstable but dynamically stable configurations, the “lively” features of the underlying quantum structure have a chance to surface to the mesocopic level and to be connected with what we observe as the phenomenon of life. This supposition can be more explicitly treated and clarified by identifying the electric dipole moment of biomolecules as the ordering parameter of the corresponding macroquantum system. This has important consequences for biology and medicine. In particular, it suggests the existence of a quantum-based “software,” essential perhaps for the logistics of biological processes, which are hidden behind the matter/energy-based “hardware” that alone is considered in the conventional approach. In medicine it opens an opportunity to build bridges between conventional medicine based essentially on the classical paradigm, and the various forms of complementary medicine, which have strong affinities with the new features of the modern holistic worldview. (shrink)

L’idée leibnizienne de la science universelle suppose l’idée de l’unité des sciences.Les signes qui doivent être créés par la caractéristique universelle appartiennent tous à la même catégorie sémantique ; ils forment une partie du vocabulaire d’un langage dans lequel toutes les sciences peuvent être exposées.Les systèmes de calcul logique contiennent une définition de la vérité. La caractéristique universelle est un langage qui n’a besoin d’aucune règle de raisonnement. Les systèmes de calcul logique se rapportent à des langues générales.

The root of the notion of “nihilism” can be taken back to the Greek sophist philosopher Gorgias. Also this notion is used in ontological and political senses. However, “nihilism” was approached by Nietzsche in terms of the “value” problem. The notion is related to the meaning of life. For Nietzsche, the notion of nihilism refers to diminishing the life’s value. Through nihilism, it is concluded that this life has no meaning. According to him, it is not possible to mention the (...) other world or a place beyond the sensory. Western metaphysics centers on the “supersensuous” and sees the world as an illusion. Thus, according to Nietzsche, “nothingness” remains. Nietzsche believes that almost all of Western metaphysics is trivializing this world and leads to nothingness, and he finds the oldest roots of nihilism in Socrates. Nietzsche’s notion of nihilism is also related to his other concepts and notions such as “God is dead”, “decadence”, “Herd human”, “Free human” and “Superman”. This research will try to express how Nietzsche gave a meaning to nihilism. Contrary to popular belief, Nietzsche was not a nihilist, rather he developed a counter philosophy against nihilism. Nietzsche’s other notions related to nihilism will also be examined to the extent permitted by our text. In addition, the problematics of nihilism will also be discussed. (shrink)

This article engages the anthropological assumptions underlying the apprehensions and promises associated with language in artificial intelligence (AI). First, we present the contours of two rivalling paradigms for assessing artificial language generation: a holistic-enactivist theory of language and an informational theory of language. We then introduce two language generation models – one presently in use and one more speculative: Firstly, the transformer architecture as used in current large language models, such as the GPT-series, and secondly, a model for 'autonomous machine (...) intelligence' recently proposed by Yann LeCun, which involves not only language but a sensory-motor interaction with the world. We then assess the language capacity of these models from the perspectives of the two rivalling language paradigms. Taking a holistic-enactivist stance, we then argue that there is currently no reason to assume a human-comparable language capacity in LLMs and, further, that LeCun's proposed model does not represent a significant step toward artificially generating human language because it still lacks essential features that underlie the linguistic capacity of humans. Finally, we suggest that proponents of these rivalling interpretations of LLMs should enter into a constructive dialogue and that this dialogue should continuously involve further empirical, conceptual, and theoretical research. (shrink)

The paper points out that the modern formulation of Bohm’s quantum theory known as Bohmian mechanics is committed only to particles’ positions and a law of motion. We explain how this view can avoid the open questions that the traditional view faces according to which Bohm’s theory is committed to a wave-function that is a physical entity over and above the particles, although it is defined on configuration space instead of three-dimensional space. We then enquire into the status of the (...) law of motion, elaborating on how the main philosophical options to ground a law of motion, namely Humeanism and dispositionalism, can be applied to Bohmian mechanics. In conclusion, we sketch out how these options apply to primitive ontology approaches to quantum mechanics in general. (shrink)

Virginia Foster Durr was born in 1903 in Birmingham, Alabama in a former planter class family, and in spite of the gradual decline in the family fortune, she was brought up as a traditional southern belle, utterly subjected to the demands of the ideology of white male supremacy that ruled the Jim Crow South. Thus, she soon learnt that in the South a black woman could not be a lady, and that as a young southern woman she was desperately (...) in need of a husband. It was not until she had fulfilled this duty that she began to open her eyes to the reality of poverty, injustice, discrimination, sexism and racism ensuing from the set of rules she had so easily embraced until then. In Outside the Magic Circle, Durr describes the process that made her aware of the gender discrimination implicit in the patriarchal southern ideology, and how this realization eventually led her to abhor racial segregation and the ideology of white male supremacy. As a consequence, in her memoirs she presents herself as a rebel facing the social ostracism resulting from her determination to fight against gender and racial discrimination in the Jim Crow South. This article delves into Durr’s composed textual self as a rebel, and suggests the existence of a crack in it, rooted in her inability to discern the real effects of white male supremacy on the domestic realm and in her subsequent blindness to the reality behind the mammy stereotype. (shrink)

Detlef Dürr (1951–2021) was a theoretical and mathematical physicist who worked particularly on the foundations of quantum mechanics, electromagnetism, and statistical mechanics. This piece is a rather personal look back at him and his science.

"Nicht die Bedingungen der Moglichkeit irgendwelcher Erkenntnisse, nicht die Voraussetzungen des Erkennens, weder die formalen noch die materialen, sondern das Erkennen selbst zu untersuchen ist die Aufgabe dieser Erkenntnistheorie. Dass etwas erkannt wird, d. h. dass in Wahrnehmungen, Erinnerungen, Gedanken, im Zweifeln, Glauben und Wissen Gegenstande erfasst werden, diese Tatsache bildet den Ausgangspunkt der folgenden Betrachtungen. Wie die verschiedenen Arten des Erkennens sich voneinander unterscheiden, aus welchen Elementarprozessen sie sich zusammensetzen und welche Gesetze ihre Entwickelung beherrschen, das sind die Fragen, (...) die von der Psychologie des Erkennens zu beantworten sind." Der Verlag der Wissenschaften verlegt historische Literatur bekannter und unbekannter wissenschaftlicher Autoren. Dem interessierten Leser werden so teilweise langst nicht mehr verlegte Werke wieder zugangig gemacht. Dieses Buch uber die Erkenntnistheorie von Dr. Ernst Durr ist ein unveranderter, hochwertiger Nachdruck der Originalausgabe aus dem Jahr 1910.". (shrink)

This volume commemorates the scientific contributions of Detlef Dürr (1951–2021) to foundational questions of physics. It presents new contributions from his former students, collaborators, and colleagues about their current research on topics inspired or influenced by Dürr. These topics are drawn from physics, mathematics, and philosophy of nature, and concern interpretations of quantum theory, new developments of Bohmian mechanics, the role of typicality, quantum physics in relativistic space-time, classical and quantum electrodynamics, and statistical mechanics. The volume thus also gives a (...) snapshot of present research in the foundations of physics. (shrink)

We review a proposal of how to complete non-relativistic Quantum Mechanics to a physically meaningful, mathematically precise and logically coherent theory. This proposal has been dubbed ETH-Approach to Quantum Mechanics, “E” standing for “Events,” “T” for “Trees,” and “H” for “Histories.” The ETH-Approach supplies the last one of three pillars Quantum Mechanics can be constructed upon in such a way that its foundations are solid and stable. Two of these pillars are well known. The third one has been proposed quite (...) recently; it implies a general non-linear stochastic law for the time-evolution of states of individual physical systems. (shrink)

in Stochastic Processes, Physics and Geometry II, edited by S. Albeverio, U. Cattaneo, D. Merlini (World Scientific, Singapore, 1995) pp. 221-232.