The perturbative approach to quantum field theory has long been viewed with suspicion by philosophers of science. This article offers a diagnosis of its conceptual problems. Drawing on Norton’s discussion of the notion of approximation I argue that perturbative QFT ought to be understood as producing approximations without specifying an underlying QFT model. This analysis leads to a reassessment of common worries about perturbative QFT. What ends up being the key issue with the approach on this picture is not mathematical (...) rigour, or the threat of inconsistency, but the need for a physical explanation of its empirical success. 1Three Worries about Perturbative Quantum Field Theory2The Perturbative Formalism 2.1Expanding the S-matrix2.2Perturbative renormalization3Approximations and Models4Perturbative Quantum Field Theory Produces Approximations5The Real Problem. (shrink)

Providing a precise statement of their position has long been a central challenge facing the scientific realist. This paper draws some morals about how realism ought to be formulated from the renormalization group framework in high energy physics.

In this article, we offer a detailed study of two important episodes in the early history of high-energy physics, namely the development of the Chew and the Nambu-Jona-Lasinio models. Our study reveals that both models resulted from the combination of an old Hamiltonian, which had been introduced by earlier researchers, and two new approximation methods developed by Chew and by Nambu and Jona-Lasinio. These new approximation methods, furthermore, were the key component behind the models’ success. We take this historical investigation (...) to support two philosophical theses about the manner in which scientific modelling operates in high-energy physics. Both of these theses run counter to a view that is commonly accepted among philosophers of science: the view that all approximations can be embedded within an equivalent idealized system, and that whatever role the former might play in scientific modelling is therefore parasitic on the much more substantial work performed by the latter. Our first thesis, which we call “Distinctness,” states that approximation methods constitute an independent category of theoretical output from idealized systems. We thus believe that approximations and idealized systems constitute two independent types of objects, both of which are essential to the practice of modelling. Our second, more radical thesis is called “Content Determination.” Our claim here is that approximation methods can in fact be essential to assigning determinate physical content to the idealized systems with which they jointly operate. As we show, this is due to the fact that quantum field theory allows for a very thin characterization of idealized systems only, making the use of approximations necessary to supply additional content. We conclude the paper with a few reflections about the manner in which our two theses can be used to articulate David Kaiser’s views on the “vanishing of scientific theory” in physics after WWII. (shrink)

The orthodox characterization of spontaneous symmetry breaking in statistical mechanics appeals to novel properties of systems with infinite degrees of freedom, namely, the existence of multiple equilibrium states. This raises the same puzzles about the status of the thermodynamic limit fueling recent debates about phase transitions. I argue that there are prospects of explaining the success of the standard approach to SSB in terms of the properties of large finite systems. Consequently, despite initial appearances, the need to account for SSB (...) phenomena does not offer decisive support to claims about the explanatory and representational indispensability of the thermodynamic limit. (shrink)

In their target article, Childress et al provide a detailed analysis of dilemmas arising from disagreement between an ICU team and a competent patient (Mr J) about dis/continuation of extra-corpore...

BackgroundECMO is a particularly scarce resource during the COVID-19 pandemic. Its allocation involves ethical considerations that may be different to usual times. There is limited pre-pandemic literature on the ethical factors that ECMO physicians consider during ECMO allocation. During the pandemic, there has been relatively little professional guidance specifically relating to ethics and ECMO allocation; although there has been active ethical debate about allocation of other critical care resources. We report the results of a small international exploratory survey of ECMO (...) clinicians’ views on different patient factors in ECMO decision-making prior to and during the COVID-19 pandemic. We then outline current ethical decision procedures and recommendations for rationing life-sustaining treatment during the COVID-19 pandemic, and examine the extent to which current guidelines for ECMO allocation (and reported practice) adhere to these ethical guidelines and recommendations.MethodsAn online survey was performed with responses recorded between mid May and mid August 2020. Participants (n = 48) were sourced from the ECMOCard study group—an international group of experts (n = 120) taking part in a prospective international study of ECMO and intensive care for patients during the COVID-19 pandemic. The survey compared the extent to which certain ethical factors involved in ECMO resource allocation were considered prior to and during the pandemic.ResultsWhen initiating ECMO during the pandemic, compared to usual times, participants reported giving more ethical weight to the benefit of ECMO to other patients not yet admitted as opposed to those already receiving ECMO, (p < 0.001). If a full unit were referred a good candidate for ECMO, participants were more likely during the pandemic to consider discontinuing ECMO from a current patient with low chance of survival (53% during pandemic vs. 33% prior p = 0.002). If the clinical team recommends that ECMO should cease, but family do not agree, the majority of participants indicated that they would continue treatment, both in usual circumstances (67%) and during the pandemic (56%).ConclusionsWe found differences during the COVID-19 pandemic in prioritisation of several ethical factors in the context of ECMO allocation. The ethical principles prioritised by survey participants were largely consistent with ECMO allocation guidelines, current ethical decision procedures and recommendations for allocation of life-sustaining treatment during the COVID-19 pandemic. (shrink)

"Mentoring the Mentor" recreates a Freirian dialogue in a printed format. In this volume, sixteen distinguished scholars engage in a critical and thoughtful exchange with Paulo Freire. While some contributors voice appreciation for Freire's ideas and for what it means to -reinvent Freire- in a North American context, others offer sharp critiques of Freire's philosophy and, of equal importance, of the various interpretations of his work. A variety of chapters describe specific uses which have been made of Freire's ideas in (...) diverse educational contexts, from the New York City public schools to the revolutions in Guinea Bissau and Eritrea. Finally, Paulo Freire himself responds to the major issues which are raised in the volume and invites readers to share in a continuing lively dialogue about the meaning of democratic and revolutionary education. -The fundamental task of the mentor is a liberatory task. It is not to encourage the mentor's goals and aspirations and dreams to be reproduced in the mentees, the students, but to give rise to the possibility that the students become the owners of their own history. This is how I understand the need that teachers have to transcend their merely instructive task and to assume the ethical posture of a mentor who truly believes in the total autonomy, freedom, and development of those he or she mentors.- (from Chapter Sixteen, -A Response- by Paulo Freire)". (shrink)

This case series presents two general practice cases where HIV testing occurred, or results suggestive of HIV were received, before informed consent was obtained. Bioethical and professional principles are used to explore these dilemmas.

"Only a wayfarer born under unruly stars would attempt to put into practice in our epoch of proliferating knowledge the Heraclitean dictum that `men who love wisdom must be inquirers into very many things indeed.'" Thus begins this remarkable interdisciplinary study of time by a master of the subject. And while developing a theory of "time as conflict," J. T. Fraser does offer "many things indeed"--an enormous range of ideas about matter, life, death, evolution, and value.

Looks at the history of the idea of time, the origins of the universe, relativity, life, the brain's perception of time, aging, death, memory, and time keeping ...

Physicists use different theories to describe the world on different scales. In particular, they use the standard model of particle physics at very high energies, but move to various effective field theories, such as quantum electrodynamics, when modelling lower energy scattering processes. One way to explain this methodological fact is pragmatic in spirit. According to this view, physicists move to an effective field theory at lower energies in order to extract predictions and qualitative understanding which would be difficult or impossible (...) to extract directly from a more fundamental theory. By contrast, another way of accounting for the methodological data is metaphysical in spirit. On this view, the reason that physicists use different theories at different scales is that the world actually exhibits different nomic structure on different scales. These two positions have recently been thrown into sharp relief in a debate between Woodward (2016) and Batterman (2021), with Woodward taking the pragmatist line and Batterman the metaphysical line. One difficulty with the metaphysical answer is that its content is unclear: in what sense exactly could an effective field theory provide a better representation of the nomic structure of the world in its domain of applicability than our world’s fundamental theory? This talk attempts to provide an answer to this question by developing a simple metaphysical model. I start by assuming a set of possible worlds which are nomically possible according to some fundamental theory (I suggest that one is free to adopt either a Humean or Non-Humean view of these fundamental nomic necessities). I then introduce an equivalence relation between possible worlds: two worlds are scale-E equivalent if they assign the same values to physical quantities below energy scale E (up to some finite level of precision P). The key question now is whether this relation induces equivalence classes on the set of nomically possible worlds. I argue that in the case of current quantum field theories this does indeed occur, as evidenced by the possibility of “integrating out” high energy degrees of freedom in the renormalisation group framework. The formation of equivalence classes in the fundamental theory's possibility space indicates that some of its high energy features do not make a difference to its low energy dynamical behaviour. This suggests the following reading of the claim that an effective field theory provides a better representation of the nomic structure of the world in its domain of applicability: the solutions of the effective field theory stand in one-to-one correspondence with equivalence classes induced by the scale-E equivalence relation, whereas the fundamental theory overcounts the physical possibilities which are relevant at scale E. In this sense, the effective field theory provides a more natural representation of low energy physics than the fundamental theory. I conclude by explaining how this metaphysical model offers a reduction compatible understanding of multiple realisability, once again pointing to renormalisation group results in quantum field theory to support this. (shrink)

This work represents a guided tour to the interdisciplinary, integrated study of time.

Decisions about long-term ventilation in children can be clinically contentious and ethically challenging. In this article, the relevant legal, professional and moral principles inherent in such cases are explored. We commend the central importance of deliberation in the assessment of best interests, and propose a practical framework to assist the parent–clinical team to reach decisions in as transparent and equitable a manner as possible.

Although many facets of Lev Vygotsky’s life have drawn considerable attention from historians of science, perhaps the most popular feature of his personal narrative was that his work was actively chastised by the Stalinist government. Almost all contemporary references to Vygotsky’s personal history emphasize that from 1936 to 1956, it was forbidden to either discuss or disseminate any of Vygotsky’s works within the Soviet Union. Although this ‘Vygotsky ban’ is both widely acknowledged and frequently cited by a variety of scholars, (...) the exact nature of this alleged Communist party censure has received far less historical attention. Through focusing on the logistics of Soviet ‘bans,’ this article attempts to shed light on this historical mystery and augment the growing body of revisionist literature that serves to deconstruct the mythologized persona of Lev Vygotsky. (shrink)

The First Conference of the International Society for the Study of Time was held at the Mathematisches Forschungsinstitut at Oberwolfach in the Black Forest, Federal Republic of Germany from Sunday, 31 August to Saturday, 6 September, 1969. The origin of this conference and the formation of the Society goes back to a proposal due to J. T. Fraser that was discussed at a conference on "Interdisciplinary Perspectives of Time" held by the New York Academy of Sciences in January, 1966. It (...) was unanimously agreed than that an international society should be formed on an interdisciplinary basis with the object of stimulating interest in all problems concerning 'time and that this object could best be attained by means of conferences held at regular intervals. J. T. Fraser was elected Secretary, S. Watanabe Treasurer, and I was elected President. It was agreed, at my suggestion, that the organization of the first conference of the newly formed Society be left to a committee of these three officers, on the understanding that they would invite authorities on the role of time in the various special sciences and humanities to form an Advisory Board to assist them. One of the main difficulties in seeking support for an interdisciplinary conference is that most foundations confine their interest exclusively either to the sciences or to the humanities. (shrink)

This eighth volume in the highly praised Study of Time series presents articles that fall into three broad categories: life and time as they are understood in the biological, cognitive, and psychological dimensions; the experience of time and life in words, sounds, and images; and time and life as ordered according to sociological, historical, and anthropological perspectives. The International Society for the Study of Time (ISST) is largely composed of the very academics whose early training and research have encouraged them (...) to specialized in subjects of less and less scope. But the very interdisciplinary nature of a society of heterogenous scholars from over 30 countries in more than 20 disciplines committed to the study of time is bound to broaden the perspective of those who are thus engaged. Furthermore, the insistence on delivering papers in plenary session - and in a milieu which has always proved to be a delight to the eyes, the mind, and the body - invariably encourages highly productive, jargon free, and very profitable discussions throughout the day and in smaller groups often late into the night. How does time and life apply to music, technology, philosophy, physics, film, and so much more? The pleasant pain and the resulting creative energy that derive from being obliged to view one's subject in a newer and broader perspective produced the excellent papers chosen for presentation at the conference. And that same creative energy is presented here in the more Apollonian form of the papers selected by their external readers and the editors, as Dimensions of Time and Life. (shrink)

ArgumentIn August of 1977, Australian pathologist David W. Buntine delivered a presentation at the Annual Meeting of the Royal College of Pathologists of Australia in Melbourne, Victoria. In this presentation, he used the diagnostic category of “Eskimoma,” to describe a unique set of salivary gland tumors he had observed over the past five years within Winnipeg’s Health Sciences Center. Only found amongst Inuit patients, these tumors were said to have unique histological, clinical, and epidemiological features and were unlike any other (...) disease category that had ever been encountered before. To understand where this nosological category came from, and its long-term impact, this paper traces the historical trajectory of the “Eskimoma.” In addition to discussing the methods and infrastructures that were essential to making the idea of Inuit cancer “visible,” to the pathologist, the epidemiologist, and to society at large, this paper discusses how Inuit tissue samples obtained, stored, and analyzed in Winnipeg, Manitoba, came to be codified into a new, racially based disease category – one that has guided Canadian and international understandings of circumpolar cancer trends and shaped northern healthcare service delivery for the past sixty years. (shrink)

From the world's foremost authority on the interdisciplinary study of time comes this remarkable work on the intersection of time and human values.

In Plautus and elsewhere in old Latin there is an imperative suffix -mino of medio-deponential meaning: opperimino, PL True. 188 , progredimino, id. Pseud. 859, arbitramino, id. Epid. 695, praefamino, Cato, RR. 141, 2, famino Paul. Fest. 62, 10, Th., all 2 sg.; in legal documents, antestamino , in the XII Tables, fruimino , CIL. 1, 199, profitemino in Lex Iulia Municipalis, all 3 sg. The generally accepted explanation of the form is that it arose from a contamination of the (...) ordinary 2 pl. medio-passive imperative in -mini and the 2, 3 sg. forms in -to, Lindsay, Latin Language, p. 517, Von Planta, Gramm. d. oskisch-umbr. Dial. II, pp. 310 sqq., Buck, Elementarb. d. oskisch-umbr. Dial. p. 112, Sommer, Hdb. d. lat. Laut- u. Formenlehre, p. 366, Stolz, Lat. Gramm*. p. 158. The Oskan and the Umbrian forms in -mo, -mu, U. spahamu, eturstahmu, persnimu, O. censamur, all of 2 or 3 sg., and U. arsmahamo, caterahamo of 2 or 3 pi., are identified with the Lat. -minō forms on the assumption that the Osk-Umbr. -mu represents an older *-mnō which in turn arose by syncope from -*menō Von Planta, l.c. This explanation is the most satisfactory that has been given, and we may suppose that Latin, Oskan, and Umbrian had an imperative form in *-menō. (shrink)

In Plautus and elsewhere in old Latin there is an imperative suffix -mino of medio-deponential meaning: opperimino, PL True. 188, progredimino, id. Pseud. 859, arbitramino, id. Epid. 695, praefamino, Cato, RR. 141, 2, famino Paul. Fest. 62, 10, Th., all 2 sg.; in legal documents, antestamino, in the XII Tables, fruimino, CIL. 1, 199, profitemino in Lex Iulia Municipalis, all 3 sg. The generally accepted explanation of the form is that it arose from a contamination of the ordinary 2 pl. (...) medio-passive imperative in -mini and the 2, 3 sg. forms in -to, Lindsay, Latin Language, p. 517, Von Planta, Gramm. d. oskisch-umbr. Dial. II, pp. 310 sqq., Buck, Elementarb. d. oskisch-umbr. Dial. p. 112, Sommer, Hdb. d. lat. Laut- u. Formenlehre, p. 366, Stolz, Lat. Gramm*. p. 158. The Oskan and the Umbrian forms in -mo, -mu, U. spahamu, eturstahmu, persnimu, O. censamur, all of 2 or 3 sg., and U. arsmahamo, caterahamo of 2 or 3 pi., are identified with the Lat. -minō forms on the assumption that the Osk-Umbr. -mu represents an older *-mnō which in turn arose by syncope from -*menō Von Planta, l.c. This explanation is the most satisfactory that has been given, and we may suppose that Latin, Oskan, and Umbrian had an imperative form in *-menō. (shrink)

The papers in this volume reflect much of the current unease of a world that perceives itself once more at the edge of chaos. The authors present different vistas of that experience and their inherent dialectic, expressed in numerous and ceaseless conflicts between ordering and disordering processes. They can be read as comments on the ongoing processes that lead toward greater complexity.

The latest elaborate work on the Saturnian goes back definitely to the view that the metre is quantitative in character, not accentual, or halfaccentual. This theory then, which is at the same time the oldest, may at present be considered to hold the field, and the burden of proof will presumably lie on those who advocate a counter-theory. In putting forward such a theory I shall make two, as I think, justifiable assumptions: that that theory should be accounted the best (...) which throws most light on the origin of the Saturnian, and that the Saturnian is an exceedingly primitive metre, and that an explanation of a primitive metre need not be very complicated to be intelligible. (shrink)