I will present the classification of physical operators in the most general bosonic effective gauge theory up to dimension six. Building on this classification, I will discuss the complete one-loop anomalous dimension, computed using both unitarity-based on-shell techniques and geometric methods. This analysis fully accounts for operator mixing across different dimensions and applies broadly...
This is the third of a series of works aimed at renormalizing the Standard Model effective field theory at one loop and to order $1/\Lambda^4$, with $\Lambda$ being the new physics cut-off. In this occasion, we concentrate on the running of two-fermion operators induced by pairs of dimension-six interactions. We work mostly off-shell, for which we obtain and provide a new and explicitly...
We present a new Mathematica package with the purpose of performing multi-loop computations. ANATAR simplifies Dirac and colour algebras by using FORM and integrates several existing tools designed for higher-order computations, which makes it very efficient without compromising user-friendliness and flexibility. Support for any BSM model with the same gauge group as the SM is provided, and in...
Functional methods are a popular choice for various RG and EFT matching calculations, although many of the techniques have so far been limited to one-loop calculations. With the increasing demand for precision calculations, we have developed new, practical methods for the multi-loop level. In this talk, I will discuss these new techniques, contrast and compare them with ordinary diagrammatic...
There is growing interest in using functional methods for multi-loop calculations, such as effective field theory matching and the calculation of renormalization group equations. Beyond one loop, instead of evaluating functional traces, one must perform tensor contractions associated with certain graphs. In this talk I will discuss my ongoing work on FunGraphs, a package that aims to automate...
We assess the impact of Renormalisation Group Equations (RGEs) in global SMEFT fits, incorporating QCD, electroweak, and Yukawa corrections. By assigning characteristic energy scales to LEP and LHC cross-sections, we quantify RGE effects on current and projected fits at the HL-LHC and FCC-ee. Additionally, we evaluate the role of RGEs in the sensitivity of these colliders to UV models matched...
We discuss a novel open-source Python package, jelli: a JAX-based EFT likelihood, which provides an easy-to-use and highly efficient framework particularly suited to global SMEFT/WET analyses and the phenomenology of heavy new physics models. The nature of the tool is generic, allowing a differentiable high-dimensional likelihood to be constructed from any set of observables and measurements...
SMEFT global analyses commonly encounter two major challenges:
1. An incomplete set of observables.
2. Ad-hoc flavour assumptions.
These issues significantly undermine the reliability and applicability of the results.
In this talk, I propose the CLEW framework for a complete global analysis free of flavour assumptions. By integrating both high- and low-energy data, our framework is able...
Motivated by the updates of the ATLAS and CMS projections of Higgs pair production at the HL-LHC and the release of the Feasibility Study of the FCC-ee, we revisit the sensitivity of the global SMEFT analysis to deformations of the Higgs trilinear self-coupling $\lambda_3$.
We critically reassess the additional information that would be provided by the FCC-ee through NLO corrections to $Zh$...
The Electric Dipole Moment of the electron (eEDM) is typically investigated in experiments using paramagnetic molecules. However, the physical observable in these searches consists in a linear combination of CP-violating interactions, rather than the eEDM alone, which is commonly referred to as the equivalent EDM of the system. Assuming the presence of new CP-odd physics from heavy degrees of...
The matching of UV models on their low-energy EFT can be obtained from a dispersion relation, analogous to the one leading to positivity constraints but generalised beyond four-point amplitudes. Introduced in 2308.00035, this method is distinct from those based on the (functional) effective action and on (off- or on-shell) amplitudes. It takes cut amplitudes as input. In particular, one-loop...
I will discuss a few issues related to anomalous dimensions of the EFT below the EW scale at two loop order.
In Effective Field Theories, evanescent operators are introduced to compensate for the breakdown of four-dimensional Dirac identities (e.g. Fierz Identities) when used in combination with dimensional regularization.
In this talk, we provide an alternative approach where contributions of evanescent operators are viewed as corrections to d=4 Dirac relations. This new perspective not only...
The 't Hooft-Veltman scheme is the only consistent prescription for handling γ5γ5 at all orders in the perturbative expansion, which is crucial for multi-loop computations. However, its application within EFT frameworks has been limited due to technical challenges.
In this talk, we will explore a practical approach to implementing this regularization scheme using functional methods. This...
We present the complete set of positivity bounds on the Higgs Effective Field Theory (HEFT) at next-to-leading order (NLO). We identify the 15 operators that can be constrained by positivity, as they contribute to $s^2$-growth in the amplitude for longitudinal gauge-Higgs scattering, that is to all possible 2-to-2 scattering processes involving longitudinal gauge bosons, $V_L = W_L^\pm, Z_L$,...
The analogy between field redefinitions in EFTs and coordinate transformations suggests that EFT amplitudes can be interpreted as geometric invariants, constructed from fundamental building blocks. We identify these building blocks as geometric quantities derived from the covariant derivatives of the action, which remain covariant in the on-shell limit under derivative-dependent field...
Scalar Lagrangians can be expressed as metrics on fibre (or jet) bundles, which in turn allows for the expression of individual vertices and diagrams in terms of geometric objects. In this talk we show how this leads to explicit covariance of on-shell amplitudes under permitted field redefinitions, as well as outlining the methods for the computation of the amplitudes.
The Standard Model and Higgs Effective Field Theories (SMEFT and HEFT) are the two well-established theoretical frameworks for the parameterization of potential new physics signals from nearly decoupled BSM sectors. They differ in the scalar field content and - most notably - in the power counting, i.e. the way they organize BSM effects into a series expansion. While it's clear that in SMEFT...
I will present the basis of dimension-eight operators associated with universal theories. Without imposing C nor P the universality assumption reduces the number of independent SMEFT operators at dimension eight from 44807 to 175. 89 of the 175 universal operators are included in the general dimension-eight operator basis in the literature. The 86 additional operators involve higher...
The contribution will report on recent results on global EFT fits of the CMS data, with particular focus on a dimension-6 SMEFT interpretation of the measurements performed in the electroweak sector of the Standard Model, including results built upon likelihoods constructed from reconstructed-level information and properly including all correlations among the various input channels.
We propose a model in which the proton is rendered absolutely stable by an IR mechanism that remains robust against unknown quantum gravity effects. An anomaly-free linear combination of baryon number and lepton flavors is gauged and spontaneously broken to a residual $Z_9$ discrete gauge symmetry, enforcing a strict selection rule in the SMEFT: baryon number violation occurs only in multiples...
Baryon and lepton number are excellent low-energy symmetries of the Standard Model (SM) that tightly constrain the form of its extensions. In this paper we investigate the possibility that these accidental symmetries are violated in the deep UV, in such a way that one multiplet necessary for their violation lives at an intermediate energy scale M above the electroweak scale. We write down the...
We study the sensitivity of COHERENT-like experiments to non-standard contributions within the so-called $\nu$WEFT framework. The latter is the most general low-energy effective field theory that includes not only the light SM fields but also additional right-handed Dirac neutrinos.
Our analysis uses the framework presented at "Consistent QFT description of non-standard neutrino...
Given the known non-negligible interplay between large-x PDFs and new physics signals, what PDFs are suitable for new physics searches?
In this talk I discuss the fine balance between the benefit of constraining PDFs with high-energy observables to reduce their uncertainties in the large-x region that is relevant for new physics searches and the risk of fitting away potential signs of new...
Suppression of interference between the SM and the dimension-six operators is well established and complicate the extraction of constraints from the LHC data. However, it can also be seen as an opportunity to motivate shape measurements. In this presentation, I will show a few examples of resurrection by differential measurements and show how they give more stable constraints when higher order...
I discuss recent progress in using geometrical methods to compute radiative corrections in quantum field theories, and give some applications to SMEFT and ChPT.
I will also briefly discuss infinite anomalous dimensions in EFTs.
The exceptionally large dataset collected by the ATLAS detector at the highest proton-proton collision energies provided by the LHC enables precision testing of the Standard Model. Many-parameter fits to precise measurements in the framework of the SM Effective Field Theory (EFT) are becoming a standard interpretation of LHC and other collider data. In this contribution an overview is given of...
In the Standard Model (SM), flavour-specific effects originate from the Higgs couplings to fermions encoded in the Yukawa matrices. UV-complete extensions of the SM typically introduce additional flavour-dependent couplings, which can significantly affect precision collider and flavour observables. In this talk, we explore the flavour structure of higher-dimensional operators in the SM...
The potential observation of a gravitational wave background compatible with a first-order phase transition (FOPT) would be a striking signature of BSM physics. In order to be able to reconstruct the underlying fundamental model, however, it is crucial to increase the precision of theoretical predictions from the thermal QFT side.
The usual approach to the computation of FOPT parameters is...
We investigate the effect of higher-dimensional marginal operators on the thermodynamics of cosmological phase transitions. Focusing on the Abelian Higgs model, we systematically match these operators, which arise at higher orders in the underlying high-temperature expansion of thermal effective field theory, and use field redefinitions to construct a complete, minimal, and gauge-invariant...
Recently, the ATLAS and CMS experiments have been accumulating increasing statistics on the production of two electroweak (EW) bosons or more, such as HH and WWZ. These multi-boson final states are essential for probing the nature of the EW symmetry-breaking sector and its potential extensions within the framework of Effective Field Theories (EFTs), both in the linear realization (SMEFT) and...
Axion-like particles (ALPs) are hypothetical pseudoscalar states that emerge as pseudo-Nambu-Goldstone bosons from the breaking of an approximate global $ U(1) $ symmetry. They appear in several extensions of the Standard Model, offering potential solutions to the strong CP problem, the muon $(g\!-\!2)$ anomaly, neutrino mass generation, and dark matter. While most collider-based studies focus...
Using the framework of the Higgs Effective Field Theory (HEFT), I will discuss multi-Higgs production via gluon-gluon fusion (ggF) and weak boson fusion (WBF). For ggF-induced multi-Higgs production, I will highlight the impact of one-loop HEFT modifications on the Higgs self-couplings and study their effects on the production rates. By including these one-loop radiative corrections and going...
The leading direct and indirect observable effects of arbitrary extra particles of spin 1 are conveniently described by a general effective theory with Proca vector bosons that belong to certain representations of the Standard Model gauge group. Assuming a good high-energy behaviour, we further restrict the possible representations of the extra vectors and derive constraints on their couplings...
A Tera-Z factory, such as FCC-ee or CEPC, will have indirect sensitivity to heavy new physics up to the tens of TeV scale through higher-order loop contributions to precision measurements at the Z-pole. These provide complementary sensitivity to potential deviations from the Standard Model typically thought to best be constrained at leading order at higher energies above the Z-pole, leading to...
The absolute machine luminosity is a crucial parameter for high-precision measurements at future colliders. Its determination relies on the precise prediction of the cross section of some reference process, which is calculated within the Standard Model (SM). It is therefore crucial to have under control the uncertainties induced by possible New Physics (NP) effects on this reference process....
In recent years, significant progress has been made in the development of automated tools that match the parameters of new physics models and the Wilson coefficients of appropriate low-energy Effective Field Theories. This talk will shed light on an extensible, hybrid tool OperatorToC++, that combines the strengths of Mathematica and C++ to facilitate the next steps beyond the matching....
ABC4EFT is a mathematica package aiming to achieve the construction and conversion of operator bases in general effective field theories. The initial release of the package integrated the automatic construction of the physical bases in general Lorentz invariant effective field theories, and now we are going to make a major update to the package to integrate the conversion among different...
With the measurement of double Higgs production within reach, it is justified to expand our interest to more exotic processes, such as three Higgs boson production. This rare process is crucial for advancing our understanding of the Higgs boson, its interactions (including self-coupling), the Higgs potential, and the mechanism of electroweak symmetry breaking (EWSB). This talk explores the...
We analyze causality and unitarity constraints
in graviton scattering amplitudes, aiming to establish new bounds on theories with $U(1)$-gravitational anomalies, such as axion models
or strongly-coupled gauge theories. For this purpose, we show the necessity of coupling these theories to gravity. We obtain a universal scale $\Lambda_{\rm caus}$ at which states with $J\geq 4$ must...
I will present a formalism based on spinor-helicity techniques that generalizes the formulation of perturbative unitarity bounds. I will discuss unitarity bounds for $N \to M$ scattering processes (with $N,M \ge 2$), which are important for high-energy future colliders. I will also address bounds for spin-2 and higher-spin theories, which are relevant for effective field theories of gravity...
