Related papers: On the $\uptheta$-vacua and CP violation
We argue that kinetic mixing between topological flux sectors generates an effective shift of the QCD $\bar\theta$ angle, thereby inducing CP-violating effects. To demonstrate this mechanism, we analyze a $(1+1)$-dimensional $U(1)\times…
Because 4-dimensional CP is a good symmetry of many higher-dimensional theories, this suggests the possible existence of a universal CP-violating phase originating from the process of compactification. Such a phase, if it existed, would not…
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…
We numerically study the phase structure of the CP(1) model in the presence of a topological $\theta$-term, a regime afflicted by the sign problem for conventional lattice Monte Carlo simulations. Using a bond-weighted tensor…
One of the major open issues in neutrino physics is the possible existence of CP violation in the neutrino sector. Such an observation would have an important impact in various domains of physics, from high energy physics to cosmology. Its…
In a recent paper[1] Kundu and one of the present authors showed that there were transient but observable CP violating effects in the decay of classical currents on the horizon of a black hole, if the Lagrangian of the Maxwell field…
A gapped many-body system is described by path integral on a space-time lattice $C^{d+1}$, which gives rise to a partition function $Z(C^{d+1})$ if $\partial C^{d+1} =\emptyset$, and gives rise to a vector $|\Psi\rangle$ on the boundary of…
QCD and related gauge theories have a sign problem when a $\theta$-term is included; this complicates the extraction of physical information from Euclidean space calculations as one would do in lattice studies. The sign problem arises in…
QCD admits a contribution to the action, the $\theta$ term, which potentially gives rise to nontrivial phases and violates CP. This is essentially a question of how the vacuum reacts to the $\theta$ term. In this talk I will address the…
In vacuum or constant density matter, the two flavor neutrino oscillation formulae are insensitive to the presence of CP violating phases owing to the fact that the CP phase can be gauged away. In sharp contrast to the above case, we show…
Geometrical CP violation is a particular type of spontaneous CP violation in which the vacuum expectation values have phases which are calculable, i.e. stable against the variation of the free parameters of the scalar potential. Although…
We introduce exactly solvable gapless quantum systems in $d$ dimensions that support symmetry protected topological (SPT) edge modes. Our construction leads to long-range entangled, critical points or phases that can be interpreted as…
We address the challenging issue of how CP violation is realized in higher dimensional gauge theories without higher dimensional elementary scalar fields. In such theories interactions are basically governed by a gauge principle and…
The unsuppressed CP violation in QCD is a problem in the standard model. If we have some mechanism to guarantee real determinants of the quark mass matrices, the vanishing physical vacuum angle $\bar \theta$ indicates the CP invariance at…
The QED(0+1) model describing a quantum mechanical particle on a circle with minimal electromagnetic interaction and with a potential -M cos(phi - theta_M), which mimics the massive Schwinger model, is discussed as a prototype of mechanisms…
In this letter we explore the spontaneous CP violation at the finite temperature. We show that the CP-violating phase $\varphi$ may only emerge around the time of the electroweak phase transition, and it can provide a scource for generating…
This article examines how the physical presence of field energy and particulate matter could influence the topological properties of space time. The theory is developed in terms of vector and matrix equations of exterior differential forms.…
In a previous publication we noted that the time dependence of an incoherent $B^0-\bar{B}^0$ mixture undergoes a qualitative change when the magnitude of CP violation $\delta$ exceeds a critical value. Requiring, on physical grounds, that…
We argue that gauge transformations with arbitrary fractional winding numbers should be allowed in a non-Abelian gauge theory. This eliminates the topological distinction between large and small gauge transformations. We prove that the…
Because present Monte Carol algorithms for lattice QCD may become trapped in a given topological charge sector when one approaches the continuum limit, it is important to understand the effect of calculating at fixed topology. In this work,…