Theory Division

There is a surprising connection between the top quark and Higgs alignment in Gildener-Weinberg multi-Higgs-doublet models. Were it not for the top quark and its large mass, the coupling of the 125 GeV Higgs boson H to gauge bosons and fermions would be indistinguishable from those of the Standard Model Higgs. The top quark’s coupling... More »

The traditional method of performing renormalization group (RG) transformations for spin systems is by spin-blocking, where the block spins are local averages of the original spins, and they live on a lattice with fewer sites than the original lattice. As such, this transformation is inherently discrete. By contrast, over the last decade a new technique known as... More »

Even though the LHC searches did not unveil the new physics particles so far, observations made at LHCb and the B-factories point towards lepton flavor universality violation in both tree-level and loop-induced B-meson semileptonic decays. After a review of the status of these anomalies, I will discuss general implications that can be derived by using... More »

Theoretical understandings of the neutrino-nucleus cross sections are critical for constraining neutrino parameters in future neutrino oscillation experiments such as DUNE and Hyper-K. For neutrino energies at around 1 GeV, uncertainties in the nucleon axial form factor, which parameterizes the weak response of a neutron or proton as a function of the four momentum transfer,... More »

The recent results from the Fermilab muon g-2 experiment have caused quite a stir in the community. At the same time, there are persisting hints of lepton flavor universality violation in some rare B-meson decays. Taken at face value, if these anomalies are interpreted as of beyond the Standard Model (BSM) origin, it is conceivable... More »

A very rich place to look for phenomena to challenge our current understanding of physics is the flavor sector of the Standard Model (SM). In particular, the $V_{cb}$ matrix element of the CKM matrix is the subject of a long standing tension, depending on whether it is determined using inclusive or exclusive methods. On top... More »

I construct various generalizations of partition function in non-supersymmetric theories, including few fairly close to QCD, that do not undergo a phase transition upon circle compactification. This is similar to what happens in supersymmetric index calculations but there it is guaranteed by supersymmetry, and Bose-Fermi grading of Hilbert space. In manifestly non-supersymmetric theories in QM,... More »

Behavior of the electroweak symmetry and the Higgs thermal history have intriguing implications for matter antimatter asymmetry creation and early universe physics. In this talk, I will present two beyond the Standard Model scenarios resulted in two different early universe paths of the electroweak symmetry. Electroweak phase transition from an electroweak symmetric phase to the... More »

I present a recent calculation of the hadronic light-by-light scattering contribution to the muon g−2 from the up, down, and strange-quark sector directly using lattice QCD. I first describe the methodology based on coordinate-space methods and a pilot calculation at the SU(3)-flavour symmetric point with a pseudoscalar mass of about 420 MeV. The final result... More »