The bootstrap approach to understanding the elementary particles in hadronic physics was very popular in the 1960s as an alternative to quantum field theory. This episode is subjected to historical, methodological and philosophical analysis designed to complement the extensive work of Jim Cushing in this field.

ArgumentIn the theory-dominated view of scientific experimentation, all relations of theory and experiment are taken on a par; namely, that experiments are performed solely to ascertain the conclusions of scientific theories. As a result, different aspects of experimentation and of the relations of theory to experiment remain undifferentiated. This in turn fosters a notion of theory-ladenness of experimentation (TLE) that is toocoarse-grainedto accurately describe the relations of theory and experiment in scientific practice. By contrast, in this article, I suggest that (...) TLE should be understood as anumbrella conceptthat has different senses. To this end, I introduce a three-fold distinction among the theories of high-energy particle physics (HEP) as background theories, model theories, and phenomenological models. Drawing on this categorization, I contrast two types of experimentation, namely, “theory-driven” and “exploratory” experiments, and I distinguish between the “weak” and “strong” senses of TLE in the context of scattering experiments from the history of HEP. This distinction enables identifying the exploratory character of the deep-inelastic electron-proton scattering experiments – performed at the Stanford Linear Accelerator Center (SLAC) between the years 1967 and 1973 – thereby shedding light on a crucial phase of the history of HEP, namely, the discovery of “scaling,” which was the decisive step towards the construction of quantum chromo-dynamics as a gauge theory of strong interactions. (shrink)

The answer to the fine-tuning problem of the universe has been traditionally sought in terms of either design or multiverse. In philosophy circles, this is sometimes expanded by adding the option of explanatory nihilism—the claim that there is no explanation for statements of that high level of generality: fine-tunings are brute facts. In this paper, we consider the fourth option which, at least in principle, is available to us: co-evolution of the universe and observers. Although conceptual roots of this approach (...) could be found already in ancient stoicism, it is still the least investigated explanatory option for resolving the problem of empirical fine tunings. We offer two preliminary models along which the co-evolution hypothesis could be developed further. They are still on the level of speculative metaphysics, but there are opportunities along the way to generate predictions which are in principle testable, especially in the domain of large-scale numerical simulations. (shrink)

This paper is a critique of a project, outlined by Laudan et al. (1986) recently in this journal, for empirically testing philosophical models of change in science by comparing them against the historical record of actual scientific practice. While the basic idea of testing such models of change in the arena of science is itself an appealing one, serious questions can be raised about the suitability of seeking confirmation or disconfirmation for large numbers of specific theses drawn from a massive (...) list of claims abstracted from the writings of a few philosophers of science. The present paper discusses what one might reasonably expect from a model of change in science and then compares some clusters of theses from Laudan et al. with developments in recent theoretical physics. The results suggest that such straightforward testing of theses may be largely inconclusive. (shrink)

Any division between scientific practice and a metalevel of the methods and goals of science is largely a false dichotomy. Since a priori, foundationist or logicist approaches to normative principles have proven unequal to the task of representing actual scientific practice, methodologies of science must be abstracted from episodes in the history of science. Of course, it is possible that such characteristics could prove universal and constant across various eras. But, case studies show that they are not in anything beyond (...) the strictures applied to everyday, commonsense reasoning (e.g., a requirement of noncontradiction in a deductive argument). Hence, even if some presently-on-offer methodology or description of past scientific practice were adequate, it need not remain so for current (‘frontier’) areas of science. For this reason, it is important to examine recent episodes in, say, high-energy physics. Results from case studies of several episodes in that field are used to argue that successful practice leads scientists to countenance essential changes in the methodological framework at the levels of the criteria employed in judging theories (i.e., what counts for an explanation and what are canons of rationality) and of the goals of science. *Partial support for this research was provided by the History and Philosophy of Science Program of the National Science Foundation under grants Nos. SES-8606472 and SES-8705469. A preliminary version of this paper was given at an HPS seminar at King's College, London University in May 1988. Helpful comments and useful criticisms were made by several colleagues, especially Ernan McMullin, Heinz Post and Simon Saunders (none of whom are to be held responsible for or necessarily even in agreement with the views expressed here.). (shrink)

In the recent philosophy of science literature, several authors have stressed the many-faceted and evolving nature of the scientific enterprise. Dudley Shapere (1984, pp. xiii-xv) characterizes a central weakness of the logical empirical program as its focus on the formal logical structure of scientific theories to the exclusion of the process by which these theories were constructed, thus ignoring the possibility of fundamental changes in the nature of science itself. He has stressed the importance of formulating a view of science (...) based on an accurate description of actual scientific practice, which includes attention to how the meaning of a scientific term is rooted in this evolving matrix of practice. Janet Kourany (1982) has attempted” …to lay the foundations for a purely empirical method for establishing a theory of science” (p. 526). In arguing that the a priori has no place in such an approach and in responding to the charge that such an empirical method cannot produce an absolutely fixed set of criteria, Kourany (p. 546) reminds us of Popper’s observation about another empirical enterprise and suggests that we apply this same admonition to our expectations for an empirical method of constructing a theory of science itself. (shrink)

The answer to the fine-tuning problem of the universe has been traditionally sought in terms of either design or multiverse. In philosophy circles, this is sometimes expanded by adding the option of explanatory nihilism – the claim that there is no explanation for statements of that high level of generality: fine-tunings are brute facts. In this paper, we consider the fourth option which, at least in principle, is available to us: co-evolution of the universe and obsevers. Although conceptual roots of (...) this approach could be found already in ancient stoicism, it is still the least investigated explanatory option for resolving the problem of empirical fine tunings. We offer two preliminary models along which the co-evolution hypothesis could be developed further. They are still on the level of speculative metaphysics, but there are opportunities along the way to generate predictions which are in principle testable, especially in the domain of large-scale numerical simulations. (shrink)

Currently, string theory represents the only advanced approach to a unification of all interactions, including gravity. In spite of the more than thirty years of its existence, the sequence of metamorphosis it ran through, and the ever more increasing number of involved physicists, until now, it did not make any empirically testable predictions. Because there are no empirical data incompatible with the quantum field theoretical standard model of elementary particle physics and with general relativity, the only motivations for string theory (...) rest in the mutual incompatibility of the standard model and of general relativity as well as in the metaphysics of the unification program of physics, aimed at a final unified theory of all interactions including gravity. But actually, it is completely unknown which physically interpretable principles could form the basis of string theory. At the moment, "string theory" is no theory at all, but rather a labyrinthic structure of mathematical procedures and intuitions which get their justification from the fact that they, at least formally, reproduce general relativity and the standard model of elementary particle physics as low energy approximations. However, there are now strong indications that string theory does not only reproduce the dynamics and symmetries of our standard model, but a plethora of different scenarios with different low energy nomologies and symmetries. String theory seems to describe not only our world, but an immense landscape of possible worlds. So far, all attempts to find a selection principle which could be motivated intratheoretically remained without success. So, recently the idea that the low energy nomology of our world, and therefore also the observable phenomenology, could be the result of an anthropic selection from a vast arena of nomologically different scenarios entered string theory. Although multiverse scenarios and anthropic selection are not only motivated by string theory, but lead also to a possible explanation for the fine tuning of the universe, they are concepts which transcend the framework defined by the epistemological and methodological rules which conventionally form the basis of physics as an empirical science. (shrink)