Related papers: Higher order corrections to the hydrogen spectrum …
We have studied the effect of hypothetical violations of Lorentz and CPT symmetry by calculating the corrections to the energy levels of hydrogen induced by the Standard-Model Extension (SME). Hydrogen studies are interesting because the…
Rovibrational transitions in the hydrogen and antihydrogen molecular ions $H_2^+$ and $\overline{H}_2^-$ offer the possibility of testing Lorentz and CPT symmetry to extremely high precision, in principle attaining $O(10^{-17})$. In this…
The Standard-Model Extension (SME) provides a theoretical framework for tests of Lorentz invariance. To date, most studies have focused on the minimal SME, which restricts attention to operators of renormalizable dimension. Here, we review…
Various aspects of the Higgs boson phenomenology of the Minimal Supersymmetric Standard Model (MSSM) are reviewed. Emphasis is put on the effects of higher-order corrections. The masses and couplings are discussed in the MSSM with real and…
A summary of recent results obtained for higher-order corrections to precision observables in the Standard Model and the Minimal Supersymmetric Standard Model is given. In the Standard Model electroweak two-loop results valid for arbitrary…
We investigate Lorentz- and CPT-violating effects in neutron and storage-ring electric dipole moment (EDM) experiments within the framework of the Standard-Model Extension (SME). For neutron EDM experiments, perturbation theory is applied…
The Standard Model Extension (SME) provides the most general observer-independent field theoretical framework for investigations of Lorentz violation. The SME lagrangian by definition contains all Lorentz-violating interaction terms that…
We examine how corrections to $S$-state energy levels, $ E_{nS}$, in hydrogenic atoms due to the finite proton size are affected by moments of the proton charge distribution. The corrections to $E_{nS}$ are computed moment by moment. The…
We extend first-order multiconfigurational symmetry-adapted perturbation theory, SAPT(MC), [Hapka M. et al. JCTC, 2021, 17], to account for double-exchange effects, where up to two electron pairs are exchanged between interacting monomers.…
The Standard-Model Extension (SME) provides a comprehensive effective field-theory framework for the study of CPT and Lorentz symmetry. This work reviews the structure and philosophy of the SME and provides some intuitive examples of…
The Standard-Model Extension, or SME, is a general framework for the study of Lorentz violation in physics. A broad variety of experiments is able to access the SME coefficient space. This proceedings briefly summarizes theory and…
Precision electroweak measurements at LEP currently check the validity of the Standard Model to about one part in a thousand. Any successful model of physics beyond the Standard Model must be consistent with these observations. The impact…
In the current paper, we construct a Lorentz-violating electrodynamics in (1+2) spacetime dimensions from the electromagnetic sector of the nonminimal Standard-Model Extension (SME) in (1+3) dimensions. Subsequently, we study some of the…
Radiative corrections in Lorentz violating (LV) models have already received a lot of attention in the literature in recent years, with many instances where a LV operator in one sector of the Standard Model Extension (SME) generates, via…
We present the results of a complete analysis of the one loop electroweak corrections to $e^-e^+\to\gamma\gamma, ~Z\gamma, ~ZZ$ in the Standard (SM) and the Minimal Supersymmetric Standard Model (MSSM). A special emphasis is put on the high…
We introduce an improved model that links the frequency shift of the $^{133}\text{Cs}$ hyperfine Zeeman transitions $\vert F = 3, m_F> \longleftrightarrow \vert F = 4, m_F >$ to the Lorentz-violating Standard-Model Extension (SME)…
Assuming Lorentz symmetry is broken by some fixed vector background, we study the spinor electrodynamics modified by two dimension-five Lorentz-violating interactions between fermions and photons. The effective polarization and…
The recoil correction of order $(Z\alpha)^6(m/M)m$ to the hydrogen energy levels is recalculated and a discrepancy existing in the literature on this correction for the 1S energy level, is resolved. An analytic expression for the correction…
Muon electron scattering experiments such as the proposed MUonE experiment, offer an opportunity for an improved measurement of the Leading Order hadronic running of $\alpha$, denoted $\Delta \alpha_{\rm{had}}$. Such a measurement could be…
The equations of motion for the Standard Model Effective Field Theory (SMEFT) differ from those in the Standard Model. Corrections due to local contact operators modify the equations of motion and impact matching results at sub-leading…