Real CP violation in a simple extension of the standard model

I present a simple three-Higgs-doublet extension of the standard model in which real CP violation takes place. The strong CP problem is attenuated by this model.Comment: 8 page

Chiral Estimates of Strong CP Violation Revisited

The effects of the CP violating $\theta$ term in the QCD Lagrangian upon low energy hadronic phenomenology are reconsidered. Strong CP violating interactions among Goldstone bosons and octet baryons are incorporated into an effective chiral Lagrangian framework. The $\theta$ term's impact upon the decays $\eta\to\pi\pi$ and $\pi^0\to\gamma\gamma$ is then investigated but found to be extremely small. A refined model independent estimate of nonanalytic contributions to the neutron electric dipole moment is also determined using velocity dependent Baryon Chiral Perturbation Theory. We obtain the approximate upper bound $|\theta| < 4.5 \times 10^{-10}$.Comment: 11 pages with 3 figures not included but available upon request, CALT-68-184

The Measure of Strong CP Violation

We investigate a controversial issue on the measure of CP violation in strong in teractions. In the presence of nontrivial topological gauge configurations, the $\theta$-term in QCD has a profound effect: it breaks the CP symmetry. The CP-violating amplitude is shown to be determined by the vacuum tunneling process, where the semiclassical method makes most sense. We discuss a long-standing dispute on whether the instanton dynamics satisfies or not the anomalous Ward identity (AWI). The strong CP violation measure, when complying with the vacuum alignment, is proportional to the topological susceptibility. We obtain an effective CP-violating lagrangian different from that provided by Baluni. To solve the IR divergence problem of the instanton computation, We present a ``classically gauged'' Georgi-Manohar model and derive an effective potential which uniquely determines an explicit $U(1)_A$ symmetry breaking sector. The CP violation effects are analyzed in this model. It is shown that the strong CP problem and the $U(1)$ problem are closely related. Some possible solutions to both problems are also discussed with new insights.Comment: 37 pages in LateX, SFU-Preprint-92-

The electric dipole moment of the neutron in chiral perturbation theory

We calculate the electric dipole moments of the neutron and the Lambda within the framework of heavy baryon chiral perturbation theory. They are induced by strong CP-violating terms of the effective Lagrangian in the presence of the vacuum angle theta_0. The construction of such a Lagrangian is outlined and we are able to give an estimate for theta_0.Comment: 17 pages, 2 figure

Techniques used to search for a permanent electric dipole moment of the 199 Hg atom and the implications for CP violation

No description supplie

Constraining CP Violating Phases of the MSSM

Possible CP violation in supersymmetric (SUSY) extensions of the Standard Model (SM) is discussed. The consequences of CP violating phases in the gaugino masses, trilinear soft supersymmetry-breaking terms and the `mu' parameter are explored. Utilizing the constraints on these parameters from electron and neutron electric dipole moments, possible CP violating effects in B-physics are shown. A set of measurements from the B-system which would overconstrain the above CP violating phases is illustrated.Comment: 14 pages, 6 figure

Correlator of Topological Charge Densities in Instanton Model in QCD

The QCD sum rule for the correlator of topological charge densities and related to it longitudinal part of the correlator of singlet axial currents is considered in the framework of instanton model. The coupling constant of eta'-meson with the singlet axial current is determined. Its value appears to be in a good coincidence with the value determined recently from the connection of the part of proton spin, carried by u,d,s quarks, with the derivative of QCD topological susceptibility. From the same sum rule eta-eta' mixing angle is found in the framework of two mixing angles model. Its value is close to that found in the chiral effective theory. The correlator of topological charge densities at large momenta is calculated.Comment: 14 pages, 2 figure

Strong CP violation and the neutron electric dipole form factor

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 the electron-neutron Schiff moment. From the existing experimental upper limits on the neutron electric dipole moment we extract constraints on the theta-parameter and compare our results with other approaches.Comment: 18 pages, 2 figures, accepted for publication in Phys. Atom. Nuc

CP violation from noncommutative geometry

If the geometry of space-time is \nc, i.e. $[x_{\mu},x_{\nu}]=i \theta_{\mu \nu}$, then \nc \cpviolng effects may be manifest at low energies. For a \nc scale $\Lambda \equiv \theta^{-1/2} \leq 2 TeV$, \cpviol from \ncg is comparable to that from the Standard Model (SM) alone: the \nc contributions to $\epsilon$ and $\epsilon'/\epsilon$ in the $K$-system, may actually dominate over the Standard Model contributions. Present data permit \ncg to be the only source of \cpviol. Furthermore the most recent findings for g-2 of the muon are consistent with predictions from \ncg. If the geometry of space-time is \nc, $i.e.$ $[x_{\mu},x_{\nu}]=i \theta_{\mu \nu}$, then \nc \cpviolng effects may be manifest at low energies. For a \nc scale $\Lambda \equiv \theta^{-1/2} \leq 2 TeV$, \cpviol from \ncg is comparable to that from the Standard Model (SM) alone: the \nc contributions to $\epsilon$ and $\epsilon'/\epsilon$ in the K-system, may actually dominate over the Standard Model contributions. Present data permit \ncg to be the only source of \cpviol. Furthermore the most recent findings for g-2 of the muon are consistent with predictions from \ncg.Comment: fixed notation, corrected some typo

Quantum Holonomy in Three-dimensional General Covariant Field Theory and Link Invariant

We consider quantum holonomy of some three-dimensional general covariant non-Abelian field theory in Landau gauge and confirm a previous result partially proven. We show that quantum holonomy retains metric independence after explicit gauge fixing and hence possesses the topological property of a link invariant. We examine the generalized quantum holonomy defined on a multi-component link and discuss its relation to a polynomial for the link.Comment: RevTex, 12 pages. The metric independence of path integral measure is justified and the case of multi-component link is discussed in detail. To be published in Physical Review