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Paul H. Frampton

Publications and source records attributed to Paul H. Frampton.

At least 199 records · Page 11Linked to original sources

Conformal N=0 d=4 Gauge Theories from AdS/CFT Superstring Duality?

Non-supersymmetric d=4 gauge theories which arise from superstring duality on a manifold $AdS_5 \times S_5/Z_p$ are cataloged for a range $2 \leq p \leq 41$. A number have vanishing two-loop gauge β-function, a necessary but not sufficient condition to be a conformal field theory.

hep-th↗

Aspects of Soft and Spontaneous CP Violation

We study four different models for CP violation: the standard (KM) model, the aspon model of spontaneous breaking and two models of soft breaking. In all except the standard model, the strong CP problem is addressed and solved. Testable predictions for the area of the unitarity triangle and for (epsilon'/epsilon)_K are emphasized. The issue of CP violation may well become the first place where the standard model of particle theory is shown definitively to be deficient. There are two reasons for expecting this to happen: (1) the strong CP problem is still not understood in the unadorned standard model and (2) the KM mechanism, although unquestionably present, may not provide the full explanation of epsilon_K and (epsilon'/epsilon)_K.

hep-ph↗

Cosmic Background Radiation Temperature Anisotropy: Position of First Doppler Peak

The purpose of the Cosmic Background Radiation (CBR) experiments is to measure the temperature anisotropy via the autocorrelation function. The partial wave $l_1$ corresponding to the first Doppler peak caused by baryon-photon oscillations at the surface of last scattering depends on the present density $Ω_0$ and the cosmological constant contribution $Ω_Λ$. We discuss this dependence on the basis of perspicuous figures.

astro-ph↗

Constraints from Precision Electroweak Data on Leptoquarks and Bileptons

Explicit expressions are derived for the oblique parameters $S$ and $T$ in certain extensions of the standard model. In particular, we consider leptoquarks and bileptons, and find phenomenological constraints on their allowed masses. Leptoquarks suggested by the neutral and charged current anomalies at HERA can give improved agreement with both $S$ and $T$. If bileptons are the only new states, the singly-charged one must be heavier than the directly-established lower limit. Finally, we study SU(15) grand unification and show that there are regions of parameter space where the theory is compatible with experimental data.

hep-ph↗

Neutron Electric Dipole Moment and Spontaneous CP Breaking

In a model where CP is spontaneously broken, the aspon model, it is shown by extending previous arguments about B decay and the value of $Re(ε^{'}/ε)$ in the kaon system, that the neutron electric dipole moment $D_n$ is bounded from below by $D_n \geq 10^{-29}$e.-cm.

hep-ph↗

Alternative Solution of Strong CP

In this talk I begin with some general discussion of the history of CP violation, then move on to aspects of a spontaneous CP violation model including the production of new particles at LHC, implications for B decay, generalized Cabibbo mixing and a reevaluation of kaon CP violation. Finally there is a summary.

hep-ph↗

Spontaneous CP Violation

In this talk I begin with some general discussion of the history of CP violation, then move on to aspects of the aspon model including the production of new particles at LHC, implications for B decay, generalized Cabibbo mixing and a reevaluation of kaon CP violation. Finally there is a summary.

hep-ph↗

Highest Energy Cosmic Rays

It is proposed that the highest energy $\sim 10^{20}$eV cosmic ray primaries are protons, decay products of a long-lived progenitor whose high kinetic energy arises from decay of a distant (cosmological) superheavy particle, G. Such a scenario can occur in e.g. SU(15) grand unification and in some preon models, but is more generic; if true, these unusual cosmic rays provide a window into new physics.

astro-ph↗

Kaon Spontaneous CP Violation Reevaluated

The CP parameters $ε$ and $ε'/ε$ are calculated in the aspon model of spontaneous CP violation, a model which solves the strong CP problem. A new range for the scale of spontaneous breaking of CP is found. It is shown that $ε'/ε$ is suppressed by $\sim x^2 v^2/(κ^2 \sin^5 θ_C) \sim 5 \times 10^{-3}$ relative to the Standard Model. If experiment finds that $ε'/ε$ is $10^{-4}$ or greater in magnitude, it will mean that the present approach to spontaneous CP violation is excluded.

hep-ph↗

S and T for Leptoquarks and Bileptons

We calculate contributions to the oblique parameters $S$ and $T$ for leptoquarks and bileptons, and find phenomenological constraints on their allowed masses. Leptoquarks suggested by the neutral and charged current anomalies at HERA can give improved agreement with both $S$ and $T$. If bileptons are the only new states, the singly-charged one must be heavier than the directly-established lower limit. We also consider SU(15) grand unification to find when it can be consistent with precision electroweak measurements.

hep-ph↗

Bileptons - Status and Prospects

Theoretical backgound for bileptonic gauge bosons is reviewed, both the SU(15) GUT model and the 3-3-1 model. Then the mass limits for bileptons are discussed coming from $e^+e^-$ scattering, polarized muon decay and muonium-antimuonium conversion. A consequence of precision electroweak data on the masses is mentioned. Discovery in $e^-e^-$ at a linear collider is emphasised.

hep-ph↗

Long-Lived Quarks?

Several lines of reasoning suggest that there might exist a non-sequential fourth generation of heavy quarks having very small mixing with light quarks and hence exceptionally long lifetime.

hep-ph↗

Longevity and Highest-Energy Cosmic Rays

It is proposed that the highest energy $\sim 10^{20}$eV cosmic ray primaries are protons, decay products of a long-lived progenitor which has propagated from typically $\sim 100$Mpc. Such a scenario can occur in e.g. SU(15) grand unification and in some preon models, but is more generic; if true, these unusual cosmic rays provide a window into new physics.

astro-ph↗

Leptoquarks

In this review there is first a survey of the HERA data. Then we discuss the theory response including querying the consistency of the data, compositeness, contact terms, and leptoquarks including as a special case the R symmetry violating squark. The SU(15) possibility for a light leptoquark is mentioned. Finally there is a summary.

hep-ph↗

Model Building

In this talk I begin with some general discussion of model building in particle theory, emphasizing the need for motivation and testability. Three illustrative examples are then described. The first is the Left-Right model which provides an explanation for the chirality of quarks and leptons. The second is the 331-model which offers a first step to understanding the three generations of quarks and leptons. Third and last is the SU(15) model which can accommodate the light leptoquarks possibly seen at HERA.

hep-ph↗

CP Violation in the Aspon Model

The aspon model spontaneously breaks CP symmetry and makes qualitatively different predictions for CP asymmetries in B decay from the KM mechanism of the Standard Model. It further predicts the existence of the aspon gauge boson and of heavy long-lived quarks, both lying below 1TeV in mass.

hep-ph↗

Strong CP and Low-energy Supersymmetry

A spontaneously-broken CP provides an alternative to the KM mechanism for CP violation with the advantage that the strong CP problem is solved. We consider, for such a model with a new gauged U(1), the incorporation of low-energy supersymmetry and find the constraints on alignment and squark degeneracy. The conclusion is that although the $\barθ$ constraints are much less severe than in other generic schemes with supersymmetry breaking and spontaneous CP violation, one restriction remains stronger than needed in the MSSM for suppression of FCNC.

hep-ph↗