Examples of uniformly moving charge distributions that possess conserved electromagnetic stress tensors are exhibited. These constitute stable systems with covariantly characterized electromagnetic mass. This note, on a topic to which Paul Dirac made a significant contribution in 1938, is dedicated to him for his 80th birthday.

When Humpty-Dumpty had his great fall nobody could put him together again. A vastly more moderate challenge is to reunite the two partial beams of a Stern-Gerlach apparatus with such precision that the original spin state is recovered. Nevertheless, as we demonstrate, a substantial loss of spin coherence always occurs, unless the experimenter is able to control the magnetic field's inhomogeneity with an accuracy of at least one part in 105.

In this series of articles the early life and work of the young Julian Schwinger are explored. In the present article, we discuss Schwinger's winding up his work at the MIT Radiation Laboratory, being offered a tenured professorship at Harvard University, getting married, and settling down into a highly productive teaching and research career.

In this series of articles the early life and work of the young Julian Schwinger is explored. After a brilliant beginning at Columbia University, where he received his Ph.D., Schwinger went to work with J. Robert Oppenheimer in Berkeley. His stay, work, and interactions with Oppenheimer are discussed.

In this series of articles the early life and work of the young Julian Schwinger are explored. In this first article, Schwinger's childhood, growing-up, and early education are discussed.

In this series of articles the early life and work of the young Julian Schwinger are explored. In the present article, Schwinger's work at the MIT Radiation Laboratory during the Second World War is described.

In this series of articles the life and work of the young Julian Schwinger are explored. In this second article in the series, Schwinger's work at Columbia University, up to the completion of his doctorate and a little after, is discussed. Schwinger soon matured into a brilliant theoretical physicist.

Julian Schwinger was one of the leading theoretical physicists of the twentieth century. His contributions are as important, and as pervasive, as those of Richard Feynman, with whom he shared the 1965 Nobel Prize for Physics. Yet, while Feynman is universally recognized as a cultural icon, Schwinger is little known even to many within the physics community. In his youth, Julian Schwinger was a nuclear physicist, turning to classical electrodynamics after World War II. In the (...) years after the war, he was the first to renormalize quantum electrodynamics. Subsequently, he presented the most complete formulation of quantum field theory and laid the foundations for the electroweak synthesis of Glashow, Weinberg, and Salam, and he made fundamental contributions to the theory of nuclear magnetic resonance, to many-body theory, and to quantum optics. He developed a unique approach to quantum mechanics, measurement algebra, and a general quantum action principle. His discoveries include 'Feynman's' parameters and 'Glauber's' coherent states; in later years he also developed an alternative to operator field theory which he called Source Theory, reflecting his profound phenomenological bent. His late work on the Thomas-Fermi model of atoms and on the Casimir effect continues to be an inspiration to a new generation of physicists. This biography describes the many strands of his research life, while tracing the personal life of this private and gentle genius. (shrink)

An epistemological interpretation of quantum mechanics hinges on the claim that the distinctive features of quantum mechanics can be derived from some distinctive features of an observational basis. Old and new variations of this theme are listed. The program has a limited success in non-relativistic quantum mechanics. The crucial issue is how far it can be extended to quantum field theory without introducing significant ontological postulates. A C*-formulation covers algebraic quantum field theory, but not the standard model. Julian (...) class='Hi'>Schwinger’s anabatic methodology extended a strict measurement-based formulation of quantum mechanics through field theory. His extension also excluded the quark hypothesis and the standard model. Quarks and local gauge invariance are postulates that go beyond the limits of an epistemological interpretation of quantum mechanics. The ontological significance ascribed to these advances depends on the role accorded ontology. (shrink)

This paper places Julian Schwinger's development of the Euclidean Green's function formalism for quantum field theory in historical context. It traces the techniques employed in the formalism back to Schwinger's work on waveguides during World War II, and his subsequent formulation of the Minkowski space Green's function formalism for quantum field theory in 1951. Particular attention is dedicated to understanding Schwinger's physical motivation for pursuing the Euclidean extension of this formalism in 1958.

Some of my colleagues will sadly not be attending the IAB World Congress in Qatar. Amongst other things, they wish to take a stand against Qatar’s human rights record and the treatment of women and...

For the last 40 years or so the is/ought gap, the fact/value distinction and the naturalistic fallacy have figured prominently in ethical debates. This longevity, however, has had an adverse side effect. So familiar have they become that they—and their respective rationales—have tended to become blurred. It is the purpose of this paper to explain why they should be kept distinct.

The first ever global overview of philosophy: how it developed around the world and impacted the cultures in which it flourished.

Van Inwagen proposes that besides simples only living organisms exist as composite objects. This paper suggests expanding van Inwagen’s ontology by also accepting composite objects in the case that physical bonding occurs (plus some extra conditions). Such objects are not living organ-isms but rather physical bodies. They include (approximately) the complete realm of inanimate ordinary objects, like rocks and tables, as well as inanimate scientific objects, like atoms and mol-ecules, the latter filling the ontological gap between simples and organisms in (...) van Inwagen’s origi-nal picture. We thus propose a compositional pluralism claiming that composition arises if and on-ly if bonding or life occurs. (shrink)

By now, it should be clear: in the face of disinformation and disaster, we cannot hot take, life hack, or meme our way to a better future. But how should we respond instead? In How to Think like a Philosopher, Julian Baggini turns to the study of reason itself for practical solutions to this question, inspired by our most eminent philosophers, past and present. Baggini offers twelve key principles for a more human, balanced, and rational approach to thinking: pay (...) attention; question everything (including your questions); watch your steps; follow the facts; watch your language; be eclectic; be a psychologist; know what matters; lose your ego; think for yourself, not by yourself; make connections, not theories; and don't give up. Each chapter is chockfull of real-world examples showing these principles at work-from the discovery of penicillin to the fight for trans rights-and how they lead to more thoughtful conclusions. More than a book of tips and tricks (or ways to be insufferably clever at parties), How to Think like a Philosopher is an invitation to develop the habits of good reasoning that our world desperately needs. (shrink)

2007 will be remembered as the year in which the Tour de France died. Race leader and likely eventual winner, Michael Rasmussen, was eliminated near the end on an allegation of doping. Since the 1960s, the idealistic drug crusaders have been on a mission to reverse the course of history, and eliminate drugs from the sport. But this “zero tolerance” strategy to drugs has failed, as 2007's Tour spectacularly showed. Only around 10–15% of professional athletes are drug tested. Currently, it (...) is illegal to use erythropoietin (EPO) or blood doping to move your haematocrit from 48 to 49% even though some people will have a normal level of 49%. A regulated permissive policy would paradoxically reduce risk to athletes. The present system creates an environment of risk to the athlete. A rational policy on doping would allow safe performance‐enhancing interventions which are consistent with the spirit of a particular sport. (shrink)

Julian Wolfreys starts with loss. All memory is the memory of loss... All that we are, all we experience, all we remember, all that we forget but which leaves nevertheless a trace on us, in us, a trace that countersigns and writes us as who we are (in effect the constellated matrix of Being's becoming): this is a process of loss. This just is loss. Loss is who we are. Loss is authentically the necessary and inescapable inessential essence of (...) Being. Loss names the ghosts, the revenants of Being, Being's others. Neither there nor not there, loss persists as the always already becoming of the thinking of Being. There is more than one loss. There is no one loss. Loss never arrives for a first time. All loss is the return of what is lost to Being's being in the world. From that starting point, the author explores the nature of being and dwelling... of memory and the nature of the traces of the past... of apparition and appearance and perception... of touch and being touched... of the material and the (a)material. In a book that draws in multiple threads from 19th- and 20th-century European literature, he references extensively Heidegger, Derrida, Lacan, Cixous, Celan, Husserl, Woolf, Joyce, Hegel, Badiou, Rilke, Merleau-Ponty, Winterson, Stockhausen and True Detective in an impressive and eclectic tour of the being-becoming-loss.". (shrink)

Mental explanations of behaviour are physical explanations of a special kind. Mental events are physical events. Mental explanations of physical behaviour are not mysterious, they designate events with physical causal powers. Mentalistic terms differ from physicalistic ones in the way they specify events: the former cite extrinsic properties, the latter intrinsic properties. The nature of explanation in general is discussed, and a naturalistic view of intentionality is proposed. The author shows why epistemological considerations rule out the elimination of "mentalistic talk" (...) from explanations of behaviour. (shrink)

El prejuicio más aciago de la filosofía es que su historia jalona rivalidades sangrientas, conflictos insuperables, superaciones radicales, reinicios absolutos, fines y clausuras. Se trata de una concepción pobre y desangelada de esta pasión que impulsa mi viaje por la tierra. El paisaje de lo trascendental se anima cuando se lo concibe como el trabajo conjunto de una saga de artistas embriagados por el pensamiento. Esto no quiere decir que se trate de una suave danza de almas bellas; por el (...) contrario, esa misma embriaguez lleva a enfrentamientos salvajes: hay interpretaciones en las que se nos va la vida, hay conceptos cuya importancia nos desvela, hay posturas que nos parecen escandalosas. Sin embargo, también cuando la danza se hace tan turbulenta que se parece más bien a una brutal pelea de box, lo que importa es esa violencia que fuerza a pensar, y no quién tiene razón. Discutimos porque pensamos juntos, nos respetamos cuando nos criticamos de forma salvaje. Así se construye el pensamiento común: en la tensión y no en la calma, en la pasión de la embriaguez que alterna afinidades radicales y diferencias que parecen irreconciliables.Este libro se propone sostener tal visión de la filosofía a través de un experimento crucial: mostrar que entrelazando a Hegel y a Deleuze podemos construir una potente ontología práctica, que tome la multiplicidad como prius, para dar cuenta del mundo y de la experiencia, donde se conjugan movimiento y devenir con identidades y persistencias. Con ese objetivo, a lo largo de estas páginas expondré a la multiplicidad como una fuerza capaz de determinarse en formas concretas y precisas. La alianza de Deleuze y Hegel nos brinda herramientas conceptuales preciosas para esa tarea: el primero nos ofrece esa ontología de la multiplicidad, mientras el segundo nos plaga de determinaciones sutiles hasta el agotamiento. Una lectura de Hegel desde una perspectiva deleuziana abre nuestros ojos a las miríadas de diferencias y al sutil recorrido incluso de lo más bajo (en su filosofía de la naturaleza hay un secreto slum naturalismo: un amor apasionado por la vileza y las formas más precarias de la existencia). Una lectura de Deleuze desde la perspectiva hegeliana abre nuestros ojos a la máquina de determinación y constitución de lo existente que se alimenta de los flujos y rizomas que lo han hecho célebre. (shrink)

The psychedelic psilocybin has shown promise both as treatment for psychiatric conditions and as a means of improving well-being in healthy individuals. In some jurisdictions (e.g., Oregon, USA), psilocybin use for both purposes is or will soon be allowed and yet, public attitudes toward this shift are understudied. We asked a nationally representative sample of 795 US Americans to evaluate the moral status of psilocybin use in an appropriately licensed setting for either treatment of a psychiatric condition or well-being enhancement. (...) Showing strong bipartisan support, participants rated the individual’s decision as morally positive in both contexts. These results can inform effective policy-making decisions around supervised psilocybin use, given robust public attitudes as elicited in the context of an innovative regulatory model. We did not explore attitudes to psilocybin use in unsupervised or non-licensed community or social settings. (shrink)

The idea that humans are by nature social and political animals can be traced back to Aristotle. More recently, it has also generated great interest and controversy in related disciplines such as anthropology, biology, psychology, neuroscience and even economics. What is it about humans that enabled them to construct a social reality of unrivalled complexity? Is there something distinctive about the human mind that explains how social lives are organised around conventions, norms, and institutions? The Routledge Handbook of Philosophy of (...) the Social Mind is an outstanding reference source to the key topics and debates in this exciting subject and is the first collection of its kind. An international team of contributors present perspectives from diverse areas of research in philosophy, drawing on comparative and developmental psychology, evolutionary anthropology, cognitive neuroscience, and behavioural economics. The thirty-two original chapters are divided into five parts: _The Evolution of Social Mind_: including the social intelligence hypothesis, co- evolution of culture and cognition, ethnic cognition, cooperation; _Developmental and Comparative Perspectives_: including primate and infant understanding of mind, shared intentionality, and moral cognition; _Mechanisms of the Moral Mind:_ including norm compliance, social emotion, and implicit attitudes; _Naturalistic Approaches to Shared and Collective Intentionality_: including joint action, team reasoning and group thinking, and social kinds; _Social Forms of Selfhood and Mindedness_: including moral identity, empathy and shared emotion, normativity and intentionality. Essential reading for students and researchers in philosophy of mind and psychology, _The Routledge Handbook of Philosophy of the Social Mind _is also suitable for those in related disciplines such as social psychology, cognitive neuroscience, economics and sociology. (shrink)

There are 4 main arguments for euthanasia: (1) arguments appealing to consistency (e.g., from passive to active euthanasia); (2) the argument from respect for autonomy; (3) appeals to justice; and (4) the argument from interests (mercy or relief of suffering). I will argue that only the last is directly relevant to active euthanasia as a medical intervention, though arguments together from autonomy and justice can in practice (through the backdoor) provide a ground for voluntary active medical euthanasia (AME).