This survey covers some of the main philosophical debates raised by the framework of effective field theories during the last decades. It is centered on three issues: whether effective field theories underpin a specific realist picture of the world, whether they support an antireductionist picture of physics, and whether they provide reasons to give up the ultimate aspiration of formulating a final and complete physical theory. Reviewing the past and current literature, we argue that effective field theories do not give convincing reasons to adopt a particular stance towards these speculative issues. They hold good prospects for asking ontologically perspicuous and sensible questions about currently accessible domains. With respect to more fundamental questions, however, the only certainty is provisional and instrumental: effective theories are currently indispensable for conducting fruitful scientific research.

In this paper, I propose a general framework for understanding renormalization by drawing on the distinction between effective and continuum Quantum Field Theories (QFTs), and offer a comprehensive account of perturbative renormalization on this basis. My central claim is that the effective approach to renormalization provides a more physically perspicuous, conceptually coherent and widely applicable framework to construct perturbative QFTs than the continuum approach. I also show how a careful comparison between the two approaches: (i) helps to dispel the mystery surrounding the success of the renormalization procedure; (ii) clarifies the various notions of renormalizability; and (iii) gives reasons to temper Butterfield and Bouatta's claim that some continuum QFTs are ripe for metaphysical inquiry (Butterfield and Bouatta, 2014).

Williams and J. Fraser have recently argued that effective field theory methods enable scientific realists to make more reliable ontological commitments in quantum field theory (QFT) than those commonly made. In this paper, I show that the interpretative relevance of these methods extends beyond the specific context of QFT by identifying common structural features shared by effective theories across physics. In particular, I argue that effective theories are best characterized by the fact that they contain intrinsic empirical limitations, and I extract from their structure one central interpretative constraint for making more reliable ontological commitments in different subfields of physics. While this is in principle good news, this constraint still raises a challenge for scientific realists in some contexts, and I bring the point home by focusing on Williams’s and J. Fraser’s defense of selective realism in QFT.

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