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arXiv · 2601.03722

Addicted to Flavour: 1976-2026

Andrzej J. Buras
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Abstract

I describe my activities in Flavour Physics from 1976 to 2026. However, this 50th anniversary is not the only motivation for this writing. The second reason is the 350th anniversary of the discovery of the first animalcula by van Leeuvanhoek in 1676. Flavour physics makes it possible to search for new animalcula at distance scales far shorter than those resolved by van Leeuwenhoek in 1676 and even shorter than those directly accessible at the Large Hadron Collider. Achieving this goal requires not only precise measurements of a wide variety of processes, but also equally precise theoretical calculations, both within the Standard Model (SM) and beyond it. In this respect, next-to-leading-order (NLO) and next-to-next-to-leading-order (NNLO) QCD calculations of various Wilson coefficients in the SM and beyond it, in which I was involved for two decades, as well as reliable treatments of non-perturbative QCD effects, are indispensable. Equally important is the proper choice of observables that are best suited to revealing these new animalcula of particle physics. Moreover, in my view it is crucial to develop strategies for the search for New Physics (NP) that go beyond the global fits that are very popular today. While effective field theories such as WET and SMEFT are formulated in terms of Wilson coefficients of the relevant operators, with correlations characteristic of the SM and of specific NP scenarios, the most direct tests of the SM and its extensions are, in my opinion, correlations among different observables that are characteristic of particular new animalcula at work. Numerous colourful plots in this article illustrate this point. I hope that these ideas are clearly conveyed in my Flavour Autobiography, which also includes my memories of many conferences, workshops, and schools, as well as related anecdotes that are not always directly connected to physics.

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Andrzej J. Buras. 2026-02-02. Addicted to Flavour: 1976-2026. https://arxiv.org/abs/2601.03722

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