Correlation functions are the building blocks in quantum field theory, from which any physical observable can be (in principle) calculated. In a theory with gauge symmetry, however, correlation functions are not physical objects, being dependent on the particular gauge fixing prescription. In this work a novel approach is presented, which allows to separately calculate, within the class of...
We present results for three-gluon vertex form factors in a relatively general kinematics using quenched lattice gauge theory. Three-gluon vertex is the key ingredient of Yang-Mills theory, reflecting its non-Abelian nature and serving as a unique testing ground for any non-perturbative approach such as Dyson-Schwinger techniques. In this work, we have focused on a partially asymmetric...
Two Higgs doublet models (2HDM) are one of the simplest and most popular extensions to the SM and predict very different scalar interactions compared to the SM. These new interactions include new triple couplings of the SM-like Higgs bosons with itself and with the new Higgs bosons present in the 2HDM. In consequence, these new triple Higgs interactions can enter at tree-level in the cross...
The Higgs boson, responsible for the mass of the SM fundamental particles, plays a central role in propounding New Physics (NP) that might shed some light on the still unanswered questions present within the standard frame of particle physics. For example, the appearance of resonances in the scattering of longitudinally polarized vector bosons (intimately related to the Higgs mechanism) would...
In this talk we will first review the Littlest Higgs model with T-parity (LHT), based on the global symmetry group SU(5) broken spontaneously to SO(5), to highlight the pathologies it presents due to the non trivial interplay between the discrete T-parity symmetry and the non-linear realization of the global symmetry. In particular, we will show that the Yukawa Lagrangian responsible for...
We present a novel benchmark application of a quantum algorithm to Feynman loop integrals. The two on-shell states of a Feynman propagator are identified with the two states of a qubit and a quantum algorithm is used to unfold the causal singular configurations of multiloop Feynman diagrams. To identify such configurations, we exploit Grover's algorithm for querying multiple solutions over...
Precision calculations needed to disentangle SM predictions from BSM effects involve the calculation of higher-order quantum corrections which pose technical challenges. An alternative to the traditional method has been proposed in the form of the loop-tree duality theorem. We present a newly found purely causal representation of the dual integrands and the definitions of several classes of...
Z' boson is a hypothetical mediator that appears in a wide variety of New Physics models, and Z' searches at the LHC have been performed in all SM visible channels, providing limits that must be taken into account non-trivially at the time of constraining each BSM proposal. To ease this task, we present a software, Z'-explorer, to automatically test Z' models against LHC data. By simply...
Electric dipole moment (EDM) searches play an crucial role in constraining CP violation sources beyond the Standard Model. We derive new bounds on the EDM of charm and bottom quarks and explore its implications for different New Physics models (1905.02513), with special attention to the so-called Manohar-Wise model, with additional color-octet scalars. For this model, we compute the full set...
Hadronic τ decays are studied as probe of new physics. We determine the dependence of several inclusive and exclusive τ observables on the Wilson coefficients of the low-energy effective theory describing charged-current interactions between light quarks and leptons. The analysis includes both strange and non-strange decay channels. The main result is the likelihood function for the Wilson...
The Scotogenic model is an economical scenario that generates neutrino masses at the 1-loop level and includes a dark matter candidate. This is achieved by means of an ad-hoc Z_2 symmetry, which forbids the tree-level generation of neutrino masses and stabilizes the lightest Z_2-odd state. Neutrino masses are also suppressed by a quartic coupling, usually denoted by λ5. While the smallness of...
We present a basis of dimension-eight Green’s functions involving Standard Model (SM) bosonic fields, consisting of 86 new operators. Rather than using algebraic identities and integration by parts, we prove the independence of these interactions in momentum space, including a discussion on evanescent bosonic operators. Our results pave the way for renormalising the SM effective field theory...
In the recent years, a series of measurements in the observables RK() and RD() concerning the semileptonic decays of the B mesons have shown hints of violations of Lepton Flavour Universality (LFU). An updated model-independent analysis of New Physics violating LFU, by using the Standard Model Effective Field Theory (SMEFT) Lagrangian with semileptonic dimension six operators at Λ = 1 TeV is...
Understanding the mechanisms in charge of ``shaping'' hadrons inside is among the most charming problems in physics. Indeed, new experimental facilities such as the EIC are planned, and an unprecedented amount of information about hadron's complexity is expected to arise. This work takes advantage of the current situation to perform the first systematic feasibility study of accessing pion's...
Extremely precise measurements in muonic hydrogen allow to extract properties from the proton, due to its impact on the energy levels. Such extractions require however from a commensurate precision for other contributions affecting the energy levels, such as two-photon exchange effects. In this talk, we compute the axial-vector meson contribution to the hyperfine splitting of muonic hydrogen,...
After fifty years of investigations, the nucleon structure is still far from being understood and continues to represent a unique test bench for QCD. Despite the enormous progresses achieved in five decades of deep-inelastic scattering (DIS) experiments, a number of crucial open questions are still on the carpet and subject of intense theoretical and experimental studies. In the last two...
In this talk I will discuss how the future Electron-Ion Collider can help us better understand the 3-dimensional partonic structure of nucleons, in particular transverse-momentum-dependent functions, focusing on di-jet and heavy-quark production processes.
The cosmological constant problem (CCP) and the formulation of consistent quantum gravity belong to the shortlist of the most important unsolved fundamental problems of physics. In the case of CCP the problem is to explain the extremely precise (55 orders in the Standard Model) fine-tuning between the independent vacuum part and the induced one, that is a function of symmetry breaking in the...
