International Journal of Modern Physics A

The author's earlier research with Professor Bruce McKellar, some 30 years ago, led to the Tucson-Melbourne three-nucleon interaction, which is still relevant today. The new significance of three-nucleon forces in determining the structure of atomic nuclei will be discussed. This has led to increased efforts to learn more about the nature of these three-nucleon interactions, both experimentally and theoretically. The recently developed no-core shell model (NCSM) has the ability to test different theoretical models for three-nucleon forces by making direct comparisons of results produced by these forces with experimental data.

The existence of a neutrino magnetic moment implies contributions to the neutrino mass via radiative corrections. We derive model-independent "naturalness" upper bounds on the magnetic moments of Dirac and Majorana neutrinos, generated by physics above the electroweak scale. For Dirac neutrinos, the bound is several orders of magnitude more stringent than present experimental limits. However, for Majorana neutrinos the magnetic moment bounds are weaker than present experimental limits if μ_ν is generated by new physics at ~ 1 TeV, and surpass current experimental sensitivity only for new physics scales > 10 – 100 TeV. The discovery of a neutrino magnetic moment near present limits would thus signify that neutrinos are Majorana particles.

We analyze the recent claim that experimental measurements of binding energies of dipole-bound anions can be understood in terms of a quantum mechanical anomaly. The discrepancy between the experimental critical dipole moments and that predicted by the anisotropic inverse square potential of a static dipole precludes such an explanation. As has long been known, in the physical problem one must include rotational structure so that the long distance behavior changes from 1/r² to 1/r⁴. In a simple model this can be shown to lead to a modification of the critical dipole moment of 20% or so, bringing it into agreement with experiment. This, together with the fact that inclusion of finite size effects does not change the critical dipole moment of the static point dipole, strongly suggests that the quantum mechanical anomaly interpretation of the formation of dipole-bound anions cannot be correct.

By ascribing a complex anticommuting variable ζ to each basic property of a field it is possible to describe all the fundamental particles as combinations of only five ζ and understand the occurrence of particle generations. An extension of space-time x to include property then specifies the 'where, when and what' of an event and allows for a generalized relativity where the gauge fields lie in the x - ζ sector and the Higgs fields in the ζ - ζ sector.

Interacting Bose gas confined by an external potential is studied using Green functions in spectral representation. The calculation is presented transparently using the equation of motion method. With this, the interplay between the condensed and the non-condensed atoms is inevitably seen. An expression for the condensate number at finite temperature is obtained in the lowest and first orders, from which depletion of bosons from the ground state is qualitatively analyzed. Finally, we discuss the behaviour of the specific heat of a trapped interacting Bose gas in the quasi-continuum limit.

Review of recent works devoted to the variation of the fine structure constant α, strong interaction and fundamental masses (Higgs vacuum) is presented. The results from Big Bang nucleosynthesis, quasar absorption spectra, and Oklo natural nuclear reactor data give us the space-time variation on the Universe lifetime scale. Comparison of different atomic clocks gives us the present time variation. Assuming linear variation with time we can compare different results. The best limit on the variation of the electron-to-proton mass ratio μ = m_e/M_p and X_e = m_e/Λ_QCD follows from the quasar absorption spectra:¹. A combination of this result and the atomic clock results^2,3 gives the best limt on variation of . The Oklo natural reactor gives the best limit on the variation of X_s = m_s/Λ_QCD where m_s is the strange quark mass:^4,5. Note that the Oklo data can not give us any limit on the variation of α since the effect of α there is much smaller than the effect of X_s and should be neglected.

Huge enhancement of the relative variation effects happens in transitions between close atomic, molecular and nuclear energy levels. We suggest several new cases where the levels are very narrow. Large enhancement of the variation effects is also possible in cold atomic and molecular collisions near Feshbach resonance.

How changing physical constants and violation of local position invariance may occur? Light scalar fields very naturally appear in modern cosmological models, affecting parameters of the Standard Model (e.g. α). Cosmological variations of these scalar fields should occur because of drastic changes of matter composition in Universe: the latest such event is rather recent (about 5 billion years ago), from matter to dark energy domination. Massive bodies (stars or galaxies) can also affect physical constants. They have large scalar charge S proportional to number of particles which produces a Coulomb-like scalar field U = S/r. This leads to a variation of the fundamental constants proportional to the gravitational potential, e.g. δα/α = k_αδ(GM/rc²). We compare different manifestations of this effect. The strongest limits⁶k_α + 0.17k_e = (-3.5 ±6) × 10^-7 and k_α + 0.13k_q = (-1 ± 17) × 10^-7 are obtained from the measurements of dependence of atomic frequencies on the distance from Sun^2,7 (the distance varies due to the ellipticity of the Earth's orbit).

A mirror sector of particles and forces provides a simple explanation of the inferred dark matter of the Universe. The status of this theory is reviewed - with emphasis on how the theory explains the impressive DAMA/NaI annual modulation signal, whilst also being consistent with the null results of the other direct detection experiments.

Quark-lepton symmetry invites consideration of the existence of sterile neutrinos. Long ago, we showed that this approach predicts large neutrino mixing amplitudes. Using a Weyl spinor approach, we show, in an analytic example, how this, and pseudo-Dirac pairing, can develop within a reduced rank version of the conventional see-saw mechanism, from small intrinsic mixing strengths. We show by numerical examples that mixing of active and sterile neutrinos can affect the structure of oscillations relevant to extraction of neutrino mixing parameters from neutrino oscillation data.

We highlight the surprising similarities between particle physics and condensed matter physics which have been emerging from recent advances in experimantal and theoretical techniques.

In this contribution to the Festschrift in honor of Bruce McKellar and Girish Joshi, I discuss a model proposed recently¹ in which the CP violating phase in the CKM matrix is identical to the phase in the Higgs potential resulting from spontaneous CP violation.

The Kane concept of quantum computation using single phosphorus donors in silicon has revolutionized the way we think about P-doped silicon devices. However, because of the enormous effort required in fabricating such devices using single atom techniques, detailed modeling and assessment of fault-tolerant operation is required to determine and optimize the scalability, and indeed feasibility, of such a vision.

We consider the continuous symmetry group underlying Born's reciprocity principle, namely the so-called quaplectic group, the semidirect product of time-space-energy-momentum coordinate transformations with the Weyl-Heisenberg group. In two dimensional Minkowski space this group is Q(1, 1) ≅ U(1, 1) ⋉ H(2), or in Euclidean space Q(2) ≅ U(2) ⋉ H(2). For the 'scalar' system in the sense of induced representations, unitary irreducible representations are carried on a Fock space equivalent to that used by Schwinger as a model of the SU(2) angular momentum algebra, or by Holman and Biedenharn as a model of SU(1,1). Using this construction we consider the branching rules and state labelling problem for the reduction of Q(2) and Q(1, 1) to the 'physical' Euclidean and Poincaré subalgebras, respectively. The results serve to illustrate the difficulties of any consideration of Born reciprocity as an extended symmetry principle of nature.

We outline some features of higher dimensional models possessing a Quark-Lepton (QL) symmetry. The QL symmetric model in five dimensions is discussed, with particular emphasis on the use of split fermions. An interesting fermionic geography which utilises the QL symmetry to suppress the proton decay rate and to motivate the flavor differences in the quark and leptonic sectors is considered. We discuss the quartification model in five dimensions and contrast the features of this model with traditional four dimensional constructs.

I discuss the implications of the SNO neutral current result for the allowed Δm² values of pseudo-Dirac pairs. In particular, for certain parameter ranges, adiabatic MSW may occur in reverse as solar neutrinos traverse the earth's atmosphere.

In this paper an overview of the Large Hadron Collider program and status is given, including a brief description of the scientific background from which this ambitious program evolved. The emphasis is on the status of the Standard Model Higgs Boson, searches for which are the key component of the LHC program. A description of the ATLAS one of the two large general purpose experiments designed to detect evidence for the Higgs Boson and other data of interest to searches for physics beyond the standard model.

Recent CSSM Lattice Collaboration studies of hadron electromagnetic structure and the exotic hadron spectrum are highlighted. The momentum dependence of quark and gluon propagators revealed in lattice simulations of full QCD are also illustrated.