Experiments and Functional Realism

International Journal of Theoretical Physics, 2000

There are still some doubts about the existence of quarks among a minority ofphysicists who believe that they could merely represent a symmetry withouthaving a physical reality. This is because a rigorous element of reality for quarkscan only correspond to free observed quarks. An independent argument in favorof the existence of quarks as real particles is given using a method

Décio Krause, 2023

The purpose of this paper is to argue that neither mathematics nor logic can be applied 'directly' to reality, but to our rational representations (or reconstructions) of it, and this is extended to scientific theories in general. The difference to other approaches (e.g., Nancy Cartwright's, Bueno & Colyvan's or Hughes') is that I call attention to something more than it is involved in such a process, namely, metamathematics. A general schema of 'elaboration' of theories, which I suppose cope with most of them, is presented and discussed. A case study is outlined, the quantum case, whose anchored description, in my opinion, demands a different metamathematics and a different logic.

2000

REPRESENTATION MODELS AS DEVICES FOR SCIENTIFIC THEORY APPLICATIONS V5. THE SEMANTIC VIEW OF SCIENTIFIC THEORIES: The Case of Models of the Nuclear Structure Analyses of the nature and structure of scientific theories have predominantly focused on formalisation. The Received View of scientific theories considers theories as axiomatised sets of sentences. In Hilbert-style formalisation theories are considered formal axiomatic calculi to which interpretation is supplied by a set of correspondence rules. The Received View has long been abandoned. The Semantic View of scientific theories also considers theories as formal systems. In the Semantic conception, a theory is identified with the class of intended models of the formal language, if the theory were to be given such linguistic form. The proponents of the Semantic View, however, hold that this class of models can be directly defined without recourse to a formal language. Just like its predecessor, the Semantic View is also not free of untenable implications. The uniting feature of the arguments in this work is the topic of theoretical representation of phenomena. The Semantic View implies that theoretical representation comes about by the use of some model, which belongs to the class that constitutes the theory. However, this is not what we see when we scrutinise the features of actual representation models in physics. In this work particular emphasis is given to how representation models are constructed in Classical Mechanics and Nuclear Physics and what conceptual resources are used in their construction. The characteristics that these models demonstrate instruct us that to regard them as families of theoretical models, as the Semantic View purports, is to obscure how they are constructed, what is used for their construction, how they function and how they relate to the theory. For instance, representation models are devices that frequently postulate physical mechanisms for which the theory does not provide explanations. Thus it seems more appropriate to claim that these representation devices mediate between theory and experiment, and at the same time possess a partial independence from theory. Furthermore, when we focus our attention to the ways by which representation models are constructed we discern that they are the result of the processes of abstraction and concrétisation. These processes are operative in theoretical representation and they demand our attention if we are to explicate how theories represent phenomena in their domains. A cknowledgements I wish to thank my supervisor, Colin Howson, for reading and criticising several earlier versions of this work, and for his patience and help during the earlier more confused times. But I owe Colin Howson a lot more, I only hope to have benefited from his acute observation skills. I would also like to thank Stathis Psillos, John Worrall, Craig Callender, Jeff Ketland and Margaret Morrison, who read earlier versions of parts of this work and offered invaluable comments. Finally, my thanks go to Antigone Nounou, George Portides and Kristin Ross for their generous help at different stages. 6.3 Further Remarks on Idealisation: The Process of Abstraction and Concrétisation 6.3.1 A Terminological Change: Abstraction and Concrétisation 196 6.3.2 The Process of Abstraction and Concrétisation 201 6.4 Conclusion Bibliography Following Suppe, let TC be the conjunction of T and C, where T is the conjunction of the theoretical postulates and C is the conjunction of the correspondence rules. Then TC designates the scientific theory that is based on L, T, and C. The above sketch of the RV contains many features the rationale and implications of which shall not be treated here. Indeed, I shall limit myself only to those features of the RV that are relevant to the main criticisms. The above version of the Received View, as well as previous versions of it, has been criticised inter alia on the following grounds: (1) On its reliance on an observation-theory distinction and in addition on an analytic-synthetic distinction. (2) On its employment of a correspondence-rule account of the interpretation of theoretical terms. (3) On its commitment to a theory consistency condition and to a meaning invariance condition. (4) On the fact that it obscures a number of epistemologically important features of scientific theories. (5) On the fact that it assigns a deductive status to empirical theories. Although the conclusive power of these criticisms is, as will be seen, doubtful, collectively they have been persuasive among philosophers of science and as a result the Logical Positivist analysis of scientific theories gradually gave room to other schools of thought.

Synthese

According to the hierarchy of models (HoM) account of scientific experimentation developed by Patrick Suppes and elaborated by Deborah Mayo, theoretical considerations about the phenomena of interest are involved in an experiment through theoretical models that in turn relate to experimental data through data models, via the linkage of experimental models. In this paper, I dispute the HoM account in the context of present-day high-energy physics (HEP) experiments. I argue that even though the HoM account aims to characterize experimentation as a model-based activity, it does not involve a modeling concept for the process of data acquisition, and it thus fails to provide a model-based characterization of the theory-experiment relationship underlying this process. In order to characterize the foregoing relationship, I propose the concept of a model of data acquisition and illustrate it in the case of the ATLAS experiment at CERN's Large Hadron Collider, where the Higgs boson was discovered in 2012. I show that the process of data acquisition in the ATLAS experiment is performed according to a model of data acquisition that specifies and organizes the experimental procedures necessary to select the data according to a predetermined set of selection criteria. I also point out that this data acquisition model is theory-laden, in the sense that the underlying data selection criteria are determined by considering the testable predictions of the theoretical models that the ATLAS experiment is aimed to test. I take this sense of theory-ladenness to indicate that the relationship between the procedures of the ATLAS experiment and the theoretical models of the phenomena of interest is first established, prior to the formation of data models, through the data acquisition model of the experiment, thus not requiring the intermediary of other types of models as suggested by the HoM account. I therefore conclude that in the context B Koray Karaca

Studies in History and Philosophy of Modern Physics , 2001

Effective field theories have been a very popular tool in quantum physics for almost two decades. And there are good reasons for this. I will argue that effective field theories share many of the advantages of both fundamental theories and phenomenological models, while avoiding their respective shortcomings. They are, for example, flexible enough to cover a wide range of phenomena, and concrete enough to provide a detailed story of the specific mechanisms at work at a given energy scale. So will all of physics eventually converge on effective field theories? This paper argues that good scientific research can be characterised by a fruitful interaction between fundamental theories, phenomenological models and effective field theories. All of them have their appropriate functions in the research process, and all of them are indispensable. They complement each other and hang together in a coherent way which I shall characterise in some detail. To illustrate all this I will present a case study from nuclear and particle physics. The resulting view about scientific theorising is inherently pluralistic, and has implications for the debates about reductionism and scientific explanation. # PII: S 1 3 5 5 -2 1 9 8 ( 0 1 ) 0 0 0 0 5 -3