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Paul H. Frampton

Publications and source records attributed to Paul H. Frampton.

At least 163 records · Page 9Linked to original sources
arXiv2003

The Fate of Dark Energy

By studying the present cosmological data, particularly on CMB, SNeIA and LSS, we find that the future fate of the universe, for simple linear models of the dark energy equation-of-state, can vary between the extremes of (I) a divergence of the scale factor in as little as 7 Gyr; (II) an infinite lifetime of the universe with dark energy dominant for all future time; (III) a disappearing dark energy where the universe asymptotes as $t \to \infty$ to $a(t) \sim t^{2/3}$ {\it i.e.} matter domination. Our dreadful conclusion is that no amount of data from our past light-cone can select between these future scenarios.

astro-ph↗
arXiv2002

Strong-Electroweak Unification at About 4 TeV

It is shown how an $SU(3)^{N}$ nonsupersymmetric quiver gauge theory can accommodate the standard model with three chiral families and unify all of $SU(3)_C$, $SU(2)_L$ and $U(1)_Y$ couplings with high accuracy at one unique scale estimated as $M \simeq 4$ TeV.

hep-ph↗
arXiv2002

Conformality and Unification of Gauge Couplings

By use of the AdS/CFT correspondence on orbifolds, models are derived which can contain the standard model of particle phenomenology. It will be assumed that the theory becomes conformally invariant at a renormalization-group fixed-point in the TeV region. A recent application to TeV unification is briefly mentioned.

hep-th↗
arXiv2002

Zeroes of the Neutrino Mass Matrix

We assume there to be precisely three left-handed neutrino states whose Majorana masses are generated by an unspecified mechanism. Were CP conserved, the symmetric neutrino mass matrix M would be real and all six of its distinct entries could be experimentally determined. But CP is not conserved so that M is likely to be complex. As a result, not all nine of its convention-independent real parameters can be determined without an appeal to theory. Thus we examine the possibility that a restricted class of neutrino mass matrices may suffice to describe current data, namely those complex symmetric matrices several of whose entries vanish. We find that there are seven acceptable textures with two independent zeroes, and we explore their contrasting phenomenological implications. Textures with more than two independent zeroes appear to be excluded by experiment.

hep-ph↗
arXiv2002

Majorana Mass Zeroes from Triplet VEV without Majoron Problem

It is shown how to obtain recently-proposed two-zero Majorana mass textures in models with three Higgs triplets with small VEVs and a sufficiently massive triplet Majoron by using abelian discrete symmetries. It is briefly discussed how in SU(5) grand unification where the triplets occur in {\bf 15}'s the neutrino textures can be related to up- and down- quark mass textures.

hep-ph↗
arXiv2002

Modified Dispersion Relations from Closed Strings in Toroidal Cosmology

A long-standing problem of theoretical physics is the exceptionally small value of the cosmological constant $Λ\sim 10^{-120}$ measured in natural Planckian units. Here we derive this tiny number from a toroidal string cosmology based on closed strings. In this picture the dark energy arises from the correlation between momentum and winding modes that for short distances has an exponential fall-off with increasing values of the momenta.The freeze-out by the expansion of the background universe for these transplanckian modes may be interpreted as a frozen condensate of the closed-string modes in the three non-compactified spatial dimensions.

hep-th↗
arXiv2002

Dark Energy from Strings

A long-standing problem of theoretical physics is the exceptionally small value of the cosmological constant $Λ\sim 10^{-120}$ measured in natural Planckian units. Here we derive this tiny number from a toroidal string cosmology based on closed strings. In this picture the dark energy arises from the correlation between momentum and winding modes that for short distances has an exponential fall-off with increasing values of the momenta. The freeze-out by the expansion of the background universe for these transplanckian modes may be interpreted as a frozen condensate of the closed-string modes in the three non-compactified spatial dimensions.

hep-th↗
arXiv2001

Zee Model Confronts SNO Data

We reexamine the solution of the minimal Zee model by comparing with the data of the SNO experiment, and conclude that the model is strongly disfavored but not yet excluded by the observations. Two extensions of the Zee model are briefly discussed both of which introduce additional freedom and can accommodate the data.

hep-ph↗
arXiv2001

Non-associative Loops for Holger Bech Nielsen

Finite groups are of the greatest importance in science. Loops are a simple generalization of finite groups: they share all the group axioms except for the requirement that the binary operation be associative. The least loops that are not themselves groups are those of order five. We offer a brief discussion of these loops and challenge the reader (especially Holger) to find useful applications for them in physics.

hep-th↗
arXiv2001

Finite-N Conformality and Gauge Coupling Unification

In this talk I review some aspects of the idea that there is an infra-red conformal fixed-point at the TeV scale. In particular, it is shown how gauge coupling unification can be achieved by TeV unification in a semi-simple gauge group.

hep-th↗
arXiv2001

Spontaneous CP Violation: Alternative to the Standard Model

We propose a model of soft CP violation that evades the strong CP problem and can describe observed CP violation in the neutral kaon sector, both direct and indirect. Our model requires two ``duark'' mesons carrying quark number two that have complex (CP-violating) bare masses and are coupled to quark pairs. Aside from the existence of these potentially observable new particles with masses of several hundred GeV, we predict a flat unitarity triangle ({\it i.e.,} no observable direct CP violation in the $B$-meson sector) and a possibly anomalous branching ratio for the decay mode $K^+\to π^++\barν ν$.

hep-ph↗
arXiv2001

Phenomenology of Anti-de-Sitter Conformal Field Theory Duality

By use of the AdS/CFT correspondence on orbifolds, models are derived which can contain the standard model of particle phenomenology. It will be assumed that the theory becomes conformally invariant at a renormalization-group fixed-point in the TeV region.

hep-ph↗
arXiv2001

Model of Soft CP Violation

We propose a model of soft CP violation that evades the strong CP problem and can describe observed CP violation in the neutral kaon sector, both direct and indirect. Our model requires two ``duark'' mesons carrying quark number two that have complex (CP-violating) bare masses and are coupled to quark pairs. Aside from the existence of these potentially observable new particles with masses of several hundred GeV, we predict a flat unitarity triangle ({\it i.e.,} no observable direct CP violation in the $B$-meson sector) and a possibly anomalous branching ratio for the decay mode $K^+\to π^++\barν ν$.

hep-ph↗
arXiv2001

Quintessence and Cosmic Microwave Background

Analytic formulas for the position of the first acoustic peak in the CMB are derived and discussed. They are generalized to the case of a time-dependent dark energy component and it is shown how the cosmic parameters $Ω_M$ and $Λ_Λ$, extracted from observations, have an intrinsic uncertainty until one knows whether the dark energy density is, or is not, time dependent.

astro-ph↗
arXiv2000

Classification of Conformality Models Based on Nonabelian Orbifolds

A systematic analysis is presented of compactifications of the IIB superstring on $AdS_5 \times S^5/Γ$ where $Γ$ is a non-abelian discrete group. Every possible $Γ$ with order $g \leq 31$ is considered. There exist 45 such groups but a majority cannot yield chiral fermions due to a certain theorem that is proved. The lowest order to embrace the nonSUSY standard $SU(3) \times SU(2) \times U(1)$ model with three chiral families is $Γ= D_4 \times Z_3$, with $g=24$; this is the only successful model found in the search. The consequent uniqueness of the successful model arises primarily from the scalar sector, prescribed by the construction, being sufficient to allow the correct symmetry breakdown.

hep-th↗
arXiv2000

Finite N AdS/CFT Correspondence for Abelian and Nonabelian Orbifolds, and Gauge Coupling Unification

Although the AdS/CFT correspondence is rigorous only for an infinite $N \to \infty$ stack of D3-branes, it can be fruitfully studied for finite $N$ as a source of gauge structures and choices for chiral fermions and complex scalars which solve the hierarchy problem by a conformal fixed point. We emphasize orbifolds $AdS_5 \times S^5/Γ$ where the resulting GFT has ${\cal N} = 0$ supersymmetry. The fact that the complex scalars are prescribed by the construction limits the possible spontaneous symmetry breaking. Both abelian and nonabelian $Γ$ are illustrated by simple examples. An accurate $sin^2 θ$ in electroweak unification can be obtained, suggesting that this approach merits further study.

hep-th↗