Model choice and crucial tests. On the empirical epistemology of the Higgs discovery. (February 2019)

• Record Type: Journal Article
• Authors: Mättig, Peter; Stöltzner, Michael
• Is Part Of: Studies in history and philosophy of modern physics. Volume 65(2019)
• Page Start: 73
• Page End: 96
• Publication Date: 2019-02
• Subjects: Physics -- Philosophy -- Periodicals; Physics -- History -- Periodicals; 530.01
• DOI: 10.1016/j.shpsb.2018.09.001
• Languages: English
• ISSNs: 1355-2198

Abstract

Abstract: Our paper discusses the epistemic attitudes of particle physicists on the discovery of the Higgs boson at the Large Hadron Collider (LHC). It is based on questionnaires and interviews made shortly before and shortly after the discovery in 2012. We show, to begin with, that the discovery of a Standard Model (SM) Higgs boson was less expected than is sometimes assumed. Once the new particle was shown to have properties consistent with SM expectations – albeit with significant experimental uncertainties –, there was a broad agreement that 'a' Higgs boson had been found. Physicists adopted a two-pronged strategy. On the one hand, they treated the particle as a SM Higgs boson and tried to establish its properties with higher precision; on the other hand, they searched for any hints of physics beyond the SM. This motivates our first philosophical thesis: the Higgs discovery, being of fundamental importance and establishing a new kind of particle, represented a crucial experiment if one interprets this notion in an appropriate sense. Duhemian underdetermination is kept at bay by embedding the LHC into the tradition of previous precision experiments and the experimental strategies thus established. Second, our case study suggests that criteria of theory (or model) preference should be understood as epistemic and pragmatic values that have to be weighed in factual research practice. The Higgs discovery led to a shift from pragmatic to epistemic values in physicists' assessment of the mechanisms of electroweak symmetry breaking. Complex criteria, such as naturalness, combine epistemic and pragmatic values, but are coherently applied by the community. Highlights: We discuss the attitudes of particle physicists on the discovery of the Higgs boson. In 2011, the community was spilt whether the Standard Model would be confirmed. We interpret the Higgs discovery as a crucial experiment within particle physics. We understand criteria of model preference as epistemic and cognitive values. The naturalness problem is an influential, yet complex value of model preference.