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Simplified models: a different perspective on models as mediators

  • Original Paper in Philosophy of Science
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Abstract

We introduce a novel point of view on the “models as mediators” framework in order to emphasize certain important epistemological questions about models in science which have so far been little investigated. To illustrate how this perspective can help answer these kinds of questions, we explore the use of simplified models in high energy physics research beyond the Standard Model. We show in detail how the construction of simplified models is grounded in the need to mitigate pressing epistemic problems concerning the uncertainty inherent in the present theoretical and experimental contexts.

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Notes

  1. See, e.g., Cartwright ( 1983), Cartwright et al. ( 1995), Hartmann ( 1995), Psillos ( 1995), Morgan and Morrison ( 1999), Plutynski ( 2001), Leonelli ( 2008), Grüne-Yanoff ( 2009), and Toon ( 2011).

  2. In this respect the situation vis-à-vis models is more tractable than that vis-à-vis theories, since models can usually be situated in a more or less clear theoretical context, whereas situating theories in their wider context (e.g. research programme (Lakatos 1970), paradigm (Kuhn 1996), or research tradition (Laudan 1977)) can be more difficult, since this context depends on more nebulous, often implicit ideas like a metaphysical or theoretical core.

  3. Some work in the philosophy of science has already noted with interest the example of simplified models (Borrelli and Stöltzner 2013).

  4. See, e.g. the ATLAS Collaboration ( 2012b), the ATLAS Collaboration ( 2015), and the CMS Collaboration ( 2013). The original paper proposing the idea of simplified models is Alwall et al. ( 2009), building on ideas in Arkani-Hamed et al. ( 2007) and related work in Arkani-Hamed et al. ( 2006), Knuteson and Mrenna ( 2006), and Hubisz et al. ( 2008).

  5. At least the existence of some Higgs mechanism was expected, since there are a variety of ways the Higgs mechanism could be realized (Borrelli and Stöltzner 2013). That the simplest realization of the mechanism, the SM Higgs, was the one discovered was perhaps somewhat surprising (and even disappointing to many theorists, who hoped for the possibility of developing new theory). Nevertheless, there remains a strong contrast between the hunt for the Higgs (mechanism) and the hunt for Beyond Standard Model physics on the basis of the difference in reliable theoretical guidance available during the two searches.

  6. One of us (Massimi, M. 2017. Perspectival Modelling, unpublished), argues that simplified models belong to a large class of what she calls “perspectival models”, whose main function is not to represent the target system. Instead their representational content is somehow sui generis, as it concerns at best possibilities rather than actual (or even fictional) states of affairs.

  7. A cross section in particle physics is an “effective area” that represents the likelihood of a scattering event given the incoming and outgoing particles. Since different transitions and decays are possible in particle physics experiments, one also needs to know the ratios of these different transitions (what is known as the branching ratio).

  8. The representational nature of simplified models is an open question worthy of investigation. Although we do not take a stand on this question here, we note as potentially relevant the idea that models may be “fictional” (Frigg 2012), “idealized” (McMullin 1985; Cartwright 1989), or even non-representational “false models” (Wimsatt 1987). For a qualified defense of the sui generis representational nature of simplified models as modeling possibilities see (Massimi, M. 2017. Perspectival Modelling, unpublished).

  9. For the relation of EFTs to the models-as-mediators framework, see in particular (Hartmann 2001).

  10. Pace (Cartwright et al. 1995). The account from Cartwright ( 1983), where an “unprepared description” of all we know empirically about the phenomenon under investigation is adapted to theory in a “prepared description”, is inapplicable in cases such as this one.

  11. A phenomenological model is a model that is constructed (primarily) on the basis of experimental or observational results, as opposed to a theoretical model, which is a model constructed (primarily) on the basis of theory.

  12. One thing that realistic superpartners do not share is the mass of the SM particle, else they would have been detected by now along with their partner SM particles. Thus, SUSY must be a broken symmetry, if it exists, so that superpartners are able to have larger masses than their SM partners.

  13. Cf. also a similar analysis of Higgs models in Borrelli and Stöltzner ( 2013).

  14. Alwall et al. ( 2009) in particular note that a major advantage of simplified models (especially the four they introduce) is that they are related to important, discriminating collider observables, e.g. mass signatures, and lepton and heavy quark counts.

  15. For a novel take on this issue please refer to the reference (Massimi, M. 2017. Perspectival Modelling, unpublished) in fn. 6 above.

  16. Cf. the detailed study of Higgs model building in Borrelli and Stöltzner ( 2013).

  17. Arkani-Hamed et al. note that “...the relation between Lagrangian parameters and observables is often obscure, and Monte Carlo [simulations] must be generated separately for every point in the Lagrangian parameter space” (Arkani-Hamed et al. 2007, 3).

  18. As noted in the introduction, the situation was quite different with the search for the Higgs. Physicists have long had strong theoretical reasons to posit the Higgs mechanism in the context of the SM (Karaca 2013; Borrelli 2015) and plausible limits to its empirical parameters (Barger and Phillips 1987; Gunion et al. 1990). Thus, to some extent, the Higgs discovery was no surprise at all for many (Dawid 2013, 37).

  19. The minimally supersymmetric standard model (MSSM) is the minimal extension of the SM that realizes supersymmetry. It introduces over 100 parameters; further constraints can be imposed to make the MSSM more empirically tractable, which reduce the number of BSM parameters to 19 in what is known as the phenomenological MSSM (pMSSM).

  20. There have been some attempts to grapple with this “inverse problem” in recent years, which attempts eventually led to the simplified models program: (Binétruy et al. 2004; Knuteson and Mrenna 2006; Arkani-Hamed et al. 2006).

  21. Similar models have been relatedly discussed under the names “developmental models” (Leplin 1980) and “exploratory models” (Gelfert 2016, Ch. 4).

  22. Some of these considerations concerning the statistical methodology of high energy physics have recently been discussed by Dawid ( 2015, 2017), Cousins ( 2017), and Staley ( 2017).

  23. These procedures are in most respects similar to those carried out during the initial runs of the LHC when searching for the Higgs. See Franklin ( 2017) for an accessible description of the experimental procedures of the LHC during the Higgs discovery. Morrison ( 2015) and Massimi and Bhimji ( 2015) discuss the role of simulation in LHC experiments.

  24. Simplified models provide “a useful starting point for characterizing positive signals of new physics” (LHC New Physics Working Group 2012, 2); “if an excess of...events is seen in LHC data, a theoretical framework in which to describe it will be essential to constraining the structure of the new physics” (Alwall et al. 2009, 1).

  25. As an example of the methodology used in particle physics, the Tevatron and LHC experiments’ first joint results are presented in (the ATLAS Collaboration et al. 2014).

References

  • Alves, D., Izaguirre, E., & Wacker, J. (2011). Where the sidewalk ends: jets and missing energy search strategies for the 7 TeV LHC. Journal of High Energy Physics, 2011(10), 012.

    Article  Google Scholar 

  • Alwall, J., Schuster, P., & Toro, N. (2009). Simplified models for a first characterization of new physics at the LHC. Physical Review D, 79(075020).

  • Arkani-Hamed, N., Kane, G., Thaler, J., & Wang, L. -T. (2006). Supersymmetry and the LHC inverse problem. Journal of High Energy Physics, 2006 (08), 70.

    Article  Google Scholar 

  • Arkani-Hamed, N., Knuteson, B., Mrenna, S., Schuster, P., Thaler, J., Toro, N., & Wang, L.-T. (2007). MARMOSET: the path from LHC data to the new standard model via on-shell effective theories. arXiv:hep-ph/0703088.

  • Bailer-Jones, D. (1999). Tracing the development of models in the philosophy of science. In Magnani, L., Nersessian, N., & Thagard, P. (Eds.), Model-based reasoning in scientific discovery (pp. 23–40). New York: Springer.

    Chapter  Google Scholar 

  • Bailer-Jones, D. (2003). When scientific models represent. International Studies in the Philosophy of Science, 17, 59–74.

    Article  Google Scholar 

  • Bain, J. (2013). Effective field theories. In Batterman, R. (Ed.), The oxford handbook of philosophy of physics (pp. 224–254). Oxford: Oxford University Press.

    Google Scholar 

  • Barger, V., & Phillips, R. (1987). Collider physics. Redwood City, CA: Addison Wesley.

    Google Scholar 

  • Binétruy, P., Kane, G., Nelson, B., Wang, L.-T., & Wang, T. (2004). Relating incomplete data and incomplete theory. Physical Review D, 70, 095006.

    Article  Google Scholar 

  • Borrelli, A. (2012). The case of the composite Higgs: the model as a “Rosetta stone” in contemporary high-energy physics. Studies in History and Philosophy of Modern Physics, 43, 195–214.

    Article  Google Scholar 

  • Borrelli, A. (2015). The story of the Higgs boson: the origin of mass in early particle physics. European Physical Journal H, 40, 1–52.

    Article  Google Scholar 

  • Borrelli, A., & Stöltzner, M. (2013). Model landscapes in the Higgs sector. In Karakostas, V., & Dieks, D. (Eds.), EPSA11 Perspectives and foundational problems in philosophy of science (pp. 241–252). Cham, Switzerland: Springer.

    Chapter  Google Scholar 

  • Cao, T. Y., & Schweber, S. (1993). The conceptual foundations and the philosophical aspects of renormalization theory. Synthese, 97, 33–108.

    Article  Google Scholar 

  • Cartwright, N. (1983). How the laws of physics lie. Oxford: Oxford University Press.

    Book  Google Scholar 

  • Cartwright, N. (1989). Nature’s capacities and their measurement. Oxford: Oxford University Press.

    Google Scholar 

  • Cartwright, N. (1999). The dappled world. Cambridge: Cambridge University Press.

    Book  Google Scholar 

  • Cartwright, N., Shomar, T., & Suárez, M. (1995). The tool box of science. In Herfel, W., Krajewski, W., Niiniluoto, I., & Wójcicki, R. (Eds.), Theories and models in scientific processes (pp. 137–149). Amsterdam and Atlanta, GA: Rodopi.

    Google Scholar 

  • Castellani, E. (2002). Reductionism, emergence, and effective field theories. Studies in History and Philosophy of Modern Physics, 33, 251–267.

    Article  Google Scholar 

  • Cousins, R. (2017). The Jeffreys-Lindley paradox and discovery criteria in high energy physics. Synthese, 194, 395–432.

    Article  Google Scholar 

  • Dawid, R. (2013). String theory and the scientific method. Cambridge: Cambridge University Press.

    Book  Google Scholar 

  • Dawid, R. (2015). Higgs discovery and the look elsewhere effect. Philosophy of Science, 82, 76–96.

    Article  Google Scholar 

  • Dawid, R. (2017). Bayesian perspectives on the discovery of the Higgs particle. Synthese, 194, 377–394.

    Article  Google Scholar 

  • Floridi, L. (2012). Big data and their epistemological challenge. Philosophy & Technology, 25, 435–437.

    Article  Google Scholar 

  • Franklin, A. (2017). The missing piece of the puzzle: the discovery of the Higgs boson. Synthese, 194, 259–274.

    Article  Google Scholar 

  • Frigg, R. (2012). Models and fiction. Synthese, 172, 251–268.

    Article  Google Scholar 

  • Frigg, R., & Hartmann, S. (2012). Models in science. In Zalta, E. (Ed.), The stanford encyclopedia of philosophy, fall 2012 edition. https://plato.stanford.edu/archives/fall2012/entries/models-science/.

  • Gelfert, A. (2016). How to do science with models. New York: Springer.

    Book  Google Scholar 

  • Giudice, G. F. (2008). Natural speaking: The naturalness criterion and physics at the LHC. In Kane, G., & Pierce, A. (Eds.), Perspectives on LHC physics (pp. 155–178). Singapore: World Scientific.

    Chapter  Google Scholar 

  • Grinbaum, A. (2012). Which fine-tuning arguments are fine? Foundations of Physics, 42, 615–631.

    Article  Google Scholar 

  • Grüne-Yanoff, T. (2009). Learning from minimal economic models. Erkenntnis, 70, 81–99.

    Article  Google Scholar 

  • Gunion, J., Haber, H., Kane, G., & Dawson, S. (1990). The Higgs hunter’s guide. Cambridge, MA: Perseus Books.

    Google Scholar 

  • Hartmann, S. (1995). Models as a tool for theory construction: some strategies of preliminary physics. In Herfel, W., Krajewski, W., Niiniluoto, I., & Wójcicki, R. (Eds.), Theories and models in scientific processes (p. 1995). Amsterdam: Rodopi.

    Google Scholar 

  • Hartmann, S. (2001). Effective field theories, reductionism and scientific explanation. Studies in History and Philosophy of Modern Physics, 32, 267–304.

    Article  Google Scholar 

  • Hubisz, J., Lykken, J., Pierini, M., & Spiropulu, M. (2008). Missing energy look-alikes with 100p b −1 at the CERN LHC. Physical Review D, 78(075008).

  • Karaca, K. (2013). The construction of the Higgs mechanism and the emergence of the electroweak theory. Studies in History and Philosophy of Modern Physics, 44, 1–16.

    Article  Google Scholar 

  • Karaca, K. (2017). A case study in experimental exploration: exploratory data selection at the Large Hadron Collider. Synthese, 194, 333–354.

    Article  Google Scholar 

  • Knuteson, B., & Mrenna, S. (2006). Bard: interpreting new frontier energy collider physics. arXiv:hep-ph/0602101.

  • Kuhn, T. (1996). The structure of scientific revolutions, 3rd edn. Chicago: University of Chicago Press.

    Book  Google Scholar 

  • Lakatos, I. (1970). Falsification and the methodology of scientific research programmes. In Lakatos, I., & Musgrave, A. (Eds.), Criticism and the growth of knowledge (pp. 91–196). Cambridge: Cambridge University Press.

    Chapter  Google Scholar 

  • Laudan, L. (1977). Progress and its problems: towards a theory of scientific growth. Berkeley: University of California Press.

    Google Scholar 

  • Leonelli, S. (2008). Performing abstraction: two ways of modelling Arabidopsis thaliana. Biology & Philosophy, 23, 509–528.

    Article  Google Scholar 

  • Leonelli, S. (2012). Classificatory theory in data-intensive science: the case of open biomedical ontologies. International Studies in the Philosophy of Science, 26, 47–65.

    Article  Google Scholar 

  • Leonelli, S. (2014). What difference does quantity make? On the epistemology of big data in biology. Big Data & Society, 1–11.

  • LHC New Physics Working Group (2012). Simplified models for LHC new physics searches. Journal of Physics G: Nuclear and Particle Physics, 39(105005).

  • Li, C. (2003). Gauge gravity and the unification of natural forces. International Studies in the Philosophy of Science, 17, 143–159.

    Article  Google Scholar 

  • Massimi, M., & Bhimji, W. (2015). Computer simulations and experiments: the case of the Higgs boson. Studies in History and Philosophy of Modern Physics, 51, 71–81.

    Article  Google Scholar 

  • Maudlin, T. (1996). On the unification of physics. The Journal of Philosophy, 93, 129–144.

    Article  Google Scholar 

  • McMullin, E. (1985). Galilean idealization. Studies in History and Philosophy of Science Part A, 16, 247–273.

    Article  Google Scholar 

  • Morgan, M., & Morrison, M. (1999). Models as mediators. Cambridge: Cambridge University Press.

    Book  Google Scholar 

  • Morrison, M. (1999). Models as autonomous agents. In Morgan, M., & Morrison, M. (Eds.), Models as mediators (pp. 38–65). Cambridge: Cambridge University Press.

    Chapter  Google Scholar 

  • Morrison, M. (2000). Unifying scientific theories. Cambridge: Cambridge University Press.

    Book  Google Scholar 

  • Morrison, M. (2015). Reconstructing reality. Oxford: Oxford University Press.

    Book  Google Scholar 

  • Morrison, M., & Morgan, M. (1999). models as mediating instruments. In Morgan, M., & Morrison, M. (Eds.), Models as mediators (pp. 10–37). Cambridge: Cambridge University Press.

    Chapter  Google Scholar 

  • Pietsch, W. (2016). The causal nature of modeling with big data. Philosophy & Technology, 29, 137– 171.

    Article  Google Scholar 

  • Plutynski, A. (2001). Modeling evolution in theory and practice. Philosophy of Science, 68, S225- -S236.

    Article  Google Scholar 

  • Psillos, S. (1995). The cognitive interplay between theories and models: the case of 19th century physics. In Herfel, W., Krajewski, W., Niiniluoto, I., & Wójcicki, R. (Eds.), Theories and models in scientific processes (pp. 105–133). Amsterdam and Atlanta, GA: Rodopi.

    Google Scholar 

  • Sklar, L. (1981). Do unborn hypotheses have rights? Pacific Philosophical Quarterly, 62, 17–29.

    Article  Google Scholar 

  • Smeenk, C. (2013). Philosophy of cosmology. In Batterman, R. (Ed.), The oxford handbook of philosophy of physics (pp. 607–652). Oxford: Oxford University Press.

    Google Scholar 

  • Staley, K. (2017). Pragmatic warrant for frequentist statistical practice: the case of high energy physics. Synthese, 194, 355–376.

    Article  Google Scholar 

  • the ATLAS Collaboration (2012a). Observation of a new particle in the search for the Standard Model Higgs boson with the ATLAS detector at the LHC. Physics Letters B, 716, 1–29.

  • the ATLAS Collaboration (2012b). Search for squarks and gluinos using final states with jets and missing transverse momentum with the ATLAS detector in \(\phantom {\dot {i}\!}\sqrt {s} = 7\) proton-proton collisions. Physics Letters B, 710, 67–85.

  • the ATLAS Collaboration (2015). Summary of the ATLAS experiment’s sensitivity to supersymmetry after LHC Run 1—interpreted in the phenomenological MSSM. Journal of High Energy Physics, 2015(10), 134.

    Article  Google Scholar 

  • the ATLAS Collaboration, the CMS Collaboration, the CDF Collaboration, & the D0 Collaboration (2014). First combination of Tevatron and LHC measurements of the top-quark mass. arXiv:http://arxiv.org/abs/1403.4427.

  • the CMS Collaboration (2012). Observation of a new boson at a mass of 125 gev with the CMS experiment at the LHC. Physics Letters B, 716, 30–61.

    Article  Google Scholar 

  • the CMS Collaboration (2013). Interpretation of searches for supersymmetry with simplified models. Physical Review D, 88, 052017.

    Article  Google Scholar 

  • the CMS Collaboration (2016). Search for new physics with the m T2 variable in all-jets final states produced in pp collisions at \(\phantom {\dot {i}\!}\sqrt {s}= 13\) TeV. Journal of High Energy Physics, 2016(10), 6.

    Article  Google Scholar 

  • Toon, A. (2011). Playing with molecules. Studies in History and Philosophy of Science Part A, 42, 580–589.

    Article  Google Scholar 

  • Wayne, A. (1996). Theoretical unity: the case of the standard model. Perspectives in Science, 4, 391–407.

    Google Scholar 

  • Williams, P. (2015). Naturalness, the autonomy of scales, and the 125 GeV Higgs. Studies in History and Philosophy of Modern Physics, 51, 82–96.

    Article  Google Scholar 

  • Wimsatt, W. (1987). False models as means to truer theories. In Nitecki, M., & Hoffman, A. (Eds.), Neutral models in biology (pp. 23–55). Oxford: Oxford University Press.

    Google Scholar 

  • Zinkernagel, H. (2002). Cosmology, particles, and the unity of science. Studies in History and Philosophy of Modern Physics, 33, 493–516.

    Article  Google Scholar 

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Acknowledgements

The authors are grateful to Wolfgang Adam and Tiziano Camporesi at CMS, and Alan Barr, Andrea Coccaro, Monica D’Onofrio, and Victoria Martin at ATLAS for discussions during visits to CERN. We also thank Arianna Borrelli, Nora Boyd, Richard Dawid, Adam Koberinski, Michael Krämer, and Margaret Morrison for helpful conversations and feedback on this paper. This research has received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (grant agreement European Consolidator Grant H2020-ERC-2014-CoG 647272 Perspectival Realism. Science, Knowledge, and Truth from a Human Vantage Point).

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  1. School of Philosophy, Psychology, and Language Sciences, University of Edinburgh, Dugald Stewart Building, 3 Charles Street, Edinburgh, EH8 9AD, UK

    C. D. McCoy & Michela Massimi

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McCoy, C.D., Massimi, M. Simplified models: a different perspective on models as mediators. Euro Jnl Phil Sci 8, 99–123 (2018). https://doi.org/10.1007/s13194-017-0178-0

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