Global Topology and Local Violation of Discrete Symmetries

Cosmological models that are locally consistent with general relativity and the standard model in which an object transported around the universe undergoes P, C and CP transformations, are constructed. This leads to generalization of the gauge fields that describe electro-weak and strong interactions by enlarging the gauge groups to include anti-unitary transformations. Gedanken experiments show that if all interactions obey Einstein causality then P, C and CP cannot be violated in these models. But another model, which would violate charge superselection rule even for an isolated system, is allowed. It is suggested that the fundamental physical laws must have these discrete symmetries which are broken spontaneously, or they must be non causal.Comment: 12 pages, 1 figure, latex, Revtex. Charge conjugation which is physically implemented in a cosmology with the appropriate topology is described in more detail. Some minor errors are corrected. Shortened to meet the page limit of Physical Review Letters to which this paper was submitte

Effects of Possible ΔB=−ΔQ\Delta B =- \Delta Q Transitions in Neutral BB Meson Decays}

We explore the possibility that the existing data on like-sign dileptons at the $\Upsilon (4S)$ resonance consist of events arising from $B_{d}^0 -\bar B_{d}^0$ mixing and also from $\Delta B = - \Delta Q$ transitions. The consequences of these nonstandard transitions for certain time-asymmetries which are likely to be measured at the $B$ factories are studied.Comment: {\LARGE \bf 10 pages, no figures, process using latex, TIFR/TH/93-5

Probing scalar particle and unparticle couplings in e+ e- -> t tbar with transversely polarized beams

In searching for indications of new physics scalar particle and unparticle couplings in e^+ e^- \to t\bar t, we consider the role of transversely polarized initial beams at e^+ e^- colliders. By using a general relativistic spin density matrix formalism for describing the particles spin states, we find analytical expressions for the squared amplitude of the process with t or \bar t polarization measured, including the anomalous coupling contributions. Thanks to the transversely polarized initial beams these contributions are first order anomalous coupling corrections to the Standard Model (SM) contributions. We present and analyse the main features of the SM and anomalous coupling contributions. We show how differences between SM and anomalous coupling contributions provide means to search for anomalous coupling manifestations at future e^+ e^- linear colliders.Comment: 28 pages in LaTeX, including 7 encapsulated PostScript figures, published versio

Quantum Tests of the Foundations of General Relativity

The role of the equivalence principle in the context of non-relativistic quantum mechanics and matter wave interferometry, especially atom beam interferometry, will be discussed. A generalised form of the weak equivalence principle which is capable of covering quantum phenomena too, will be proposed. It is shown that this generalised equivalence principle is valid for matter wave interferometry and for the dynamics of expectation values. In addition, the use of this equivalence principle makes it possible to determine the structure of the interaction of quantum systems with gravitational and inertial fields. It is also shown that the path of the mean value of the position operator in the case of gravitational interaction does fulfill this generalised equivalence principle.Comment: Classical and Quantum Gravity 15, 13 (1998

CP Violation and Lifetime Differences of Neutral B Mesons from Correlated B^0-B^0bar Pairs

We present a technique to determine the CP violating phases, as well as, the lifetime differences of the mass eigenstates for both $B_d$ and $B_s$, by considering correlated $B\bar{B}$ pairs produced at the $\Upsilon$ resonances. We do not require a detailed time dependent study, but only partial time integrated rates, with the tag time, either preceding or following the decay of the other $B$ meson to a final state f. f may be a CP eigenstate or a non-CP eigenstate.Comment: 11 Pages Revte

Detecting new physics contributions to the D0-D0bar mixing through their effects on B decays

New physics effects may yield a detectable mass difference in the D0-D0bar system, Delta m_D. Here we show that this has an important impact on some B --> D decays. The effect involves a new source of CP violation, which arises from the interference between the phases in the B --> D decays and those in the D0-D0bar system. This interference is naturally large. New physics may well manifest itself through Delta m_D contributions to these B decays.Comment: 10 pages, Revtex, no figures. To appear in PR

Dual Computations of Non-abelian Yang-Mills on the Lattice

In the past several decades there have been a number of proposals for computing with dual forms of non-abelian Yang-Mills theories on the lattice. Motivated by the gauge-invariant, geometric picture offered by dual models and successful applications of duality in the U(1) case, we revisit the question of whether it is practical to perform numerical computation using non-abelian dual models. Specifically, we consider three-dimensional SU(2) pure Yang-Mills as an accessible yet non-trivial case in which the gauge group is non-abelian. Using methods developed recently in the context of spin foam quantum gravity, we derive an algorithm for efficiently computing the dual amplitude and describe Metropolis moves for sampling the dual ensemble. We relate our algorithms to prior work in non-abelian dual computations of Hari Dass and his collaborators, addressing several problems that have been left open. We report results of spin expectation value computations over a range of lattice sizes and couplings that are in agreement with our conventional lattice computations. We conclude with an outlook on further development of dual methods and their application to problems of current interest.Comment: v1: 18 pages, 7 figures, v2: Many changes to appendix, minor changes throughout, references and figures added, v3: minor corrections, 22 page

The Molecular Pathogenesis of Osteosarcoma: A Review

Osteosarcoma is the most common primary malignancy of bone. It arises in bone during periods of rapid growth and primarily affects adolescents and young adults. The 5-year survival rate for osteosarcoma is 60%–70%, with no significant improvements in prognosis since the advent of multiagent chemotherapy. Diagnosis, staging, and surgical management of osteosarcoma remain focused on our anatomical understanding of the disease. As our knowledge of the molecular pathogenesis of osteosarcoma expands, potential therapeutic targets are being identified. A comprehensive understanding of these mechanisms is essential if we are to improve the prognosis of patients with osteosarcoma through tumour-targeted therapies. This paper will outline the pathogenic mechanisms of osteosarcoma oncogenesis and progression and will discuss some of the more frontline translational studies performed to date in search of novel, safer, and more targeted drugs for disease management

A model for decoherence of entangled beauty

In the context of the entangled $B^0 \bar B^0$ state produced at the $\Upsilon(4S)$ resonance, we consider a modification of the usual quantum-mechanical time evolution with a dissipative term, which contains only one parameter denoted by $\lambda$ and respects complete positivity. In this way a decoherence effect is introduced in the time evolution of the 2-particle $B^0 \bar B^0$ state, which becomes stronger with increasing distance between the two particles. While our model of time evolution has decoherence for the 2-particle system, we assume that, after the decay of one of the two B mesons, the resulting 1-particle state obeys the purely quantum-mechanical time evolution. From the data on dilepton events we derive an upper bound on $\lambda$. We also show how $\lambda$ is related to the so-called ``decoherence parameter'' $\zeta$, which parameterizes decoherence in neutral flavoured meson--antimeson systems.Comment: 11 pages, revtex. Two references and some comments added, version to be published in Phys. Rev.

Spin, gravity, and inertia

The gravitational effects in the relativistic quantum mechanics are investigated. The exact Foldy-Wouthuysen transformation is constructed for the Dirac particle coupled to the static spacetime metric. As a direct application, we analyze the non-relativistic limit of the theory. The new term describing the specific spin (gravitational moment) interaction effect is recovered in the Hamiltonian. The comparison of the true gravitational coupling with the purely inertial case demonstrates that the spin relativistic effects do not violate the equivalence principle for the Dirac fermions.Comment: Revtex, 12 pages, no figures, accepted in Phys. Rev. Let