Related papers: Strong CP problem, Neutron EDM and Thermal QCD sum…
We analyze the CP-violating electric dipole form factor of the nucleon in the framework of covariant baryon chiral perturbation theory. We give a new upper bound on the vacuum angle, |\theta_0| \lesssim 2.5 \cdot 10^{-10}. The quark mass…
We investigate the possibility of the spontaneous breaking of CP symmetry in 4D SU(2) Yang-Mills at $\theta=\pi$, which has recently attracted much attention in the context of the higher-form symmetry and the 't Hooft anomaly matching…
We consider the scattering of quasi-particles off the boundary created during a first order electroweak phase transition. Spatial coherence is lost due to the quasi-quark damping rate, and we show that reflection on the boundary is…
In order to generate the baryon asymmetry of the Universe sufficiently strong CP violation is needed. It was therefore proposed that at finite temperature there might be spontaneous (transitional) CP violation within the bubble walls at the…
It is a well--known problem that in supersymmetric models there are new CP--violating phases which, if unsuppressed, would give a neutron electric dipole moment $10^2$ to $10^3$ times the present experimental limit. Here we propose that…
We calculate the neutron electric dipole form factor induced by the CP violating theta-term of QCD, within a perturbative chiral quark model which includes pion and kaon clouds. On this basis we derive the neutron electric dipole moment and…
One may argue that QCD solves the strong CP problem by itself, without having to introduce new symmetries and particles. To test this idea, a lattice simulation is performed. The problem is investigated in the CP$^3$ model first. It is…
We present a detailed study of the electric dipole moment of the neutron induced by a vacuum theta angle within the framework of QCD sum rules. At next-to-next-to leading order in the operator product expansion, we find the result…
Electric dipole moments (EDMs), which are sought as evidence of CP violation, require lattice calculations to connect constraints from experiments to limits on the strong CP violation within QCD or CP violation in new physics beyond the…
Setting aside anthropic arguments, there is no reason for CP symmetry to be obeyed within the theory of quantum chromodynamics. However, no such violation of CP symmetry has ever been observed in a strongly interacting experiment. This is…
Considering the CP violating phases, we analyze the neutron electric dipole moment (EDM) in a CP violating supersymmetric extension of the standard model where baryon and lepton numbers are local gauge symmetries(BLMSSM). The contributions…
New sources of CP violation, beyond the known sources in the standard model (SM), are required to explain the baryon asymmetry of the universe. Measurement of a non-zero permanent electric dipole moment (EDM) for fundamental particles, such…
Three hard problems! In this talk I investigate the long-distance properties of quantum chromodynamics in the presence of a topological theta term. This is done on the lattice, using the gradient flow to isolate the long-distance modes in…
Finite temperature QCD sum rules are applied to the behaviour of charmonium and bottonium states, leading to their survival at and beyond the critical temperature for deconfinement. Di-muon production in heavy-ion collisions in the…
Taking into account the additional operators coming up at finite temperature, we investigate the mass and residue of the nucleon in the framework of thermal QCD sum rules. We observe that the mass and residue of the nucleon are initially…
The question of CP violating phases and electric dipole moments (EDMs)for the electron ($d_e$) and the neutron ($d_n$) for supergravity models with nonuniversal soft breaking is considered for models with a light ($\stackrel{<}{\sim}$1 TeV)…
We study the spontaneous CP breaking at finite temperature in the Higgs sector in the Minimal Supersymmetric Standard Model with a gauge singlet. We consider the contribution of the standard model particles and that of stops, charginos,…
In a 4D four-fermion model we study the dynamical restoration of Lorentz and CPT symmetries at finite temperature. We evaluate the gap equation both at zero and at finite temperature and observe that, depending on the parameters of the…
The saturation of the two Weinberg sum rules is studied at finite temperature, using recent independent QCD sum rule results for the thermal behaviour of hadronic parameters in the vector and axial-vector channels. Both sum rules are very…
The neutron electric dipole moment is investigated in a supersymmetric electroweak model admitting $ {\rm SU(2)}_W $ singlet and $ Q = -1/3 $, say $ D $-type, quarks. Significant $ CP $ violating phases appear in the coupling between the…