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About 40 years ago, since no viable candidate for "dark matter" was discovered, M. Milgrom and J. Bekenstein introduced a non-covariant modfication of gravitational theory ((MOND) to account for the anomalpous rotation curves of galaxies. Bekenstein and Sanders then developed a relativistically covariant form of the theory, called TeVeS, involvimg scalar and tensor fields which accounts for the rotation currves as well asfor the observed lensing of background radiation around galaxies without the introduction of "dark matter". The dynamical behavior of a particle in such a gravitational theory has recently been discussed by Horwitz, Gershon and Schiffer. In this paper we study the dynamics of the $N \geq 2$ particle problem in the framework of the TeVeS theory., 5 pages, no figures

We use a one dimensional model of a square barrier embedded in an infinite potential well to demonstrate that tunneling leads to a complex behavior of the wave function and that the degree of complexity may be quantified by use of a locally defined spatial entropy function defined by S=-\int |\Psi(x,t)|^2 \ln |\Psi(x,t)|^2 dx . We show that changing the square barrier by increasing the height or width of the barrier not only decreases the tunneling but also slows down the rapid rise of the entropy function, indicating that the locally defined entropy growth is an essentially quantum effect.

We show that there exists an underlying manifold with a conformal metric and compatible connection form, and a metric type Hamiltonian (which we call the geometrical picture) that can be put into correspondence with the usual Hamilton-Lagrange mechanics. The requirement of dynamical equivalence of the two types of Hamiltonians, that the momenta generated by the two pictures be equal for all times, is sufficient to determine an expansion of the conformal factor, defined on the geometrical coordinate representation, in its domain of analyticity with coefficients to all orders determined by functions of the potential of the Hamilton-Lagrange picture, defined on the Hamilton-Lagrange coordinate representation, and its derivatives. Conversely, if the conformal function is known, the potential of a Hamilton-Lagrange picture can be determined in a similar way. We show that arbitrary local variations of the orbits in the Hamilton-Lagrange picture can be generated by variations along geodesics in the geometrical picture and establish a correspondence which provides a basis for understanding how the instability in the geometrical picture is manifested in the instability of the original Hamiltonian motion., Comment: 17 pages, titles of references given, keywords added

We use an one dimensional model of a square barrier embedded in an infinite potential well to demonstrate that tunneling leads to a complex behavior of the wave function and that the degree of complexity may be quantified by use of the spatial entropy function defined by S = -\int |\Psi(x,t)|^2 ln |\Psi(x,t)|^2 dx. There is no classical counterpart to tunneling, but a decrease in the tunneling in a short time interval may be interpreted as an approach of a quantum system to a classical system. We show that changing the square barrier by increasing the height/width do not only decrease the tunneling but also slows down the rapid rise of the entropy function, indicating that the entropy growth is an essentially quantum effect., Comment: 14 pages, 8 figures

This article provides a detailed overview of the rationale for key aspects of the protocol of the Digitalis Investigation Group (DIG) trial. It also highlights unusual aspects of the study implementation and the baseline characteristics. The DIG trial is a large, simple, international placebo-controlled trial whose primary objective is to determine the effect of digoxin on all cause mortality in patients with clinical heart failure who are in sinus rhythm and whose ejection fraction isor = 0.45. An ancillary study examines the effect in those with an ejection fraction0.45. Key aspects of the trial include the simplicity of the design, broad eligibility criteria, essential data collection, and inclusion of various types of centers. A total of 302 centers in the United States and Canada enrolled 7788 patients between February 1991 and September 1993. Follow-up continued until December 1995 with the results available in Spring 1996.

The Stueckelberg formulation of a manifestly covariant relativistic classical and quantum mechanics is briefly reviewed and it is shown that in this framework a simple (semiclassical) model exists for the description of neutrino oscillations. The model is shown to be consistent with the field equations and the Lorentz force (developed here without and with spin by canonical methods) for Glashow-Salam-Weinberg type non-Abelian fields interacting with the leptons. We discuss a possible fundamental mechanism, in the context of a relativistic theory of spin for (first quantized) quantum mechanical systems, for CP violation. The model also predicts a possibly small "pull back", i.e., early arrival of a neutrino beam, for which the neutrino motion is almost everywhere within the light cone, a result which may emerge from future long baseline experiments designed to investigate neutrino transit times with significantly higher accuracy than presently available., Revised to take into account the more recent experimental results and a discussion of a mechanism for CP violation intrinsic to the theory

A necessary condition for the emergence of chaos is given. It is well known that the emergence of chaos requires a positive exponent which entails diverging trajectories. Here we show that this is not enough. An additional necessary condition for the emergence of chaos in the region where the trajectory of the system goes through, is that the product of the maximal positive exponent times the duration in which the system configuration point stays in the unstable region should exceed unity. We give a theoretical analysis justifying this result and a few examples., Comment: 5 pages, 6 figures

In this letter we show that although the application of standard Lyapunov analysis predicts that completely integrable Kepler motion is unstable, the geometrical analysis of Horwitz et al [1] predicts the observed stability. This seems to us to provide evidence for both the incompleteness of the standard Lyapunov analysis and the strength of the geometrical analysis. Moreover, we apply this approach to the three body problem in which the third body is restricted to move on a circle of large radius which induces an adiabatic time dependent potential on the second body. This causes the second body to move in a very interesting and intricate but periodic trajectory; however, the standard Lyapunov analysis, as well as methods based on the parametric variation of curvature associated with the Jacobi metric, incorrectly predict chaotic behavior. The geometric approach predicts the correct stable motion in this case as well., Comment: 9 pages, 14 figures

Gauge fields associated with the manifestly covariant dynamics of particles in $(3,1)$ spacetime are five-dimensional. In this paper we explore the old problem of fields generated by a source undergoing hyperbolic motion in this framework. The 5D fields are computed numerically using absolute time $\tau$-retarded Green-functions, and qualitatively compared with Maxwell fields generated by the same motion. We find that although the zero mode of all fields coincides with the corresponding Maxwell problem, the non-zero mode should affect, through the Lorentz force, the observed motion of test particles., Comment: 36 pages, 8 figures

We introduce a self-adjoint operator that indicates the direction of time within the framework of standard quantum mechanics. That is, as a function of time its expectation value decreases monotonically for any initial state. This operator can be defined for any system governed by a Hamiltonian with a uniformly finitely degenerate, absolutely continuous and semibounded spectrum. We study some of the operator's properties and illustrate them for a large equivalence class of scattering problems. We also discuss some previous attempts to construct such an operator, and show that the no-go theorems developed in this context are not applicable to our construction., Comment: 5 pages, 2 figures

We review the classical and quantum mechanics of Stueckelberg, and introduce the compensation fields necessary for the gauge covariance of the Stueckelberg- Schr��dinger equation. To achieve this, one must introduce a fifth, Lorentz scalar, compensation field, in addition to the four vector fields which compensate the action of the space-time derivatives. A generalized Lorentz force can be derived from the classical Hamilton equations associated with this evolution function. We show that the fifth (scalar) field can be eliminated through the introduction of a conformal metric on the spacetime manifold. The geodesic equation associated with this metric coincides with the Lorentz force, and is therefore dynamically equivalent. Since the generalized Maxwell equations for the five dimensional fields provide an equation relating the fifth field with the spacetime density of events, one can derive the spacetime event density associated with the Friedmann-Robertson-Walker solution of the Einstein equations. The resulting density, in the conformal coordinate space, is isotropic and homogeneous, decreasing as the square of the Robertson-Walker scale factor. Using the Einstein equations, one sees that both for the static and matter dominated models, the conformal time slice in which the events which generate the world lines are contained becomes progressively thinner as the inverse square of the scale factor, establishing a simple correspondence between the configurations predicted by the underlying Friedmann-Robertson-Walker dynamical model and the configurations in the conformal coordinates., Plain TeX, 9 pages

We solve the problem of formulating Brownian motion in a relativistically covariant framework in 3+1 dimensions. We obtain covariant Fokker-Planck equations with (for the isotropic case) a differential operator of d'Alembert form. Treating the spacelike and timelike fluctuations separately in order to maintain the covariance property, we show that it is essential to take into account the analytic continuation of "unphysical" fluctuations. We discuss the notion of locality in this framework and possible implications for entangled states., Comment: 19 pages Latex, one figure ps

Using the Gell-Mann-Hartle-Griffiths formalism in the framework of the Flesia-Piron form of the Lax-Phillips theory we show that the Schr��edinger equation may be derived as a condition of stability of histories. This mechanism is realized in a mathematical structure closely related to the Zeno effect., 14 pages

We review the application of the Wigner-Weisskopf model for the neutral K meson system in the resolvent formalism. The Wigner-Weisskopf model is not equivalent to the Lee-Oehme-Yang-Wu formulation (which provides an accurate representation of the data). The residues in the pole approximation in the Wigner-Weisskopf model are not orthogonal, leading to additional interference terms in the $K_S-K_L 2\pi$ channel. We show that these terms would be detectable experimentally in the decay pattern of the beam emitted from a regenerator if the Wigner-Weisskopf theory were correct. The consistency of the data with the Lee-Oehme-Yang-Wu formulation appears to rule out the applicability of the Wigner-Weisskopf theory to the problem of neutral K meson decay., Comment: Minor clarifications included

A brief summary of the mathematical structure of the Lee-Friedrichs model is given, including the natural extension of its Hamiltonian to a Gel'fand triple, containing a generalized eigenstate for the complex pole. Contains references to some physical applications and relativistic generalizations., Comment: To be published in Kluwer Encyclopedia of Mathematics;review

The problem of the classical non-relativistic electromagnetically kicked oscillator can be cast into the form of an iterative map on phase space. The original work of Zaslovskii {\it et al} showed that the resulting evolution contains a stochastic flow in phase space to unbounded energy. Subsequent studies have formulated the problem in terms of a relativistically charged particle in interaction with the electromagnetic field. We review the standard derivation of the covariant Lorentz force, and review the structure of the relativistic equations used to study this problem. We show that the Lorentz force equation can be derived as well from the manifestly covariant mechanics of Stueckelberg in the presence of a standard Maxwell field. We show how this agreement is achieved, and criticize some of the fundamental assumptions underlying these derivations. We argue that a more complete theory, involving ``off-shell'' electromagnetic fields should be utilized. We then discuss the formulation of the off-shell electromagnetism implied by the full gauge invariance of the Stueckelberg mechanics (based on its quantized form), and show that a more general class of physical phenomena can occur., Comment: Plain TeX, 13 pages. Additional reference and remarks

The formulas for the temperature dependences of the non-strange and strange quark condensates are derived by taking into account the contribution of the massive resonances. Critical temperature of the chiral symmetry restoration transition is established to be 190 MeV if only meson resonances are considered, and 175 MeV if both meson and baryon resonances are taken into account., Comment: 16 pages, LaTeX, 2 postscript figures

We review here the microcanonical and canonical ensembles constructed on an underlying generalized quantum dynamics and the algebraic properties of the conserved quantities. We discuss the structure imposed on the microcanonical entropy by the equilibrium conditions., Comment: TeX, 11 pages. Revised

More than twenty years have passed since the threads of the `proper time formalism' in covariant classical and quantum mechanics were brought together to construct a canonical formalism for the relativistic mechanics of many particles. Drawing on the work of Fock, Stueckelberg, Nambu, Schwinger, and Feynman, the formalism was raised from the status of a purely formal mathematical technique to a covariant evolution theory for interacting particles. In the context of this theory, solutions have been found for the relativistic bound state problem, classical and quantum scattering in relativistic potentials, as well as applications in statistical mechanics. It has been shown that a generalization of the Maxwell theory is required in order that the electromagnetic interaction be well-posed in the theory. The resulting theory of electromagnetism involves a fifth gauge field introduced to compensate for the dependence of the gauge transformation on the invariant time parameter; permitting such dependence relaxes the requirement that individual particles be on fixed mass shells and allows exchange of mass during scattering. In this paper, we develop the quantum field theory of off-shell electromagnetism, and use it to calculate certain elementary processes, including Compton scattering and M{\o}ller scattering. These calculations lead to {\em qualitative} deviations from the usual scattering cross-sections, which are, however, small effects, but may be visible at small angles near the forward direction. The familiar IR divergence of the M{\o}ller scattering is, moreover, completely regularized., Comment: Requires FEYNMAN.TEX macro for Feynman diagrams. 72 pages

We study here the algebraic structure of the conserved generators from which the microcanonical and canonical ensembles are constructed on an underlying generalized quantum dynamics, and the flows they induce on the phase space. We also discuss briefly the structure of the microcanonical and canonical ensembles., Comment: 15 pages, plain TeX. Corrected report number only

We prove the uncertainty relation $T_{\triangle V}\triangle m\stackrel{>}{\sim }2\pi \hbar /c^2,$ which is realized on a statistical mechanical level for an ensemble of events in $(1+D)$-dimensional spacetime with motion parametrized by an invariant ``proper time'' $\tau ,$ where $T_{\triangle V}$ is the average passage interval in $\tau $ for the events which pass through a small (typical) $(1+D)$-volume $\triangle V,$ and $\triangle m$ is the dispersion of mass around its on-shell value in such an ensemble. We show that a linear mass spectrum is a completely general property of a $(1+D)$-dimensional off-shell theory., Comment: Latex, 13 pages

We discuss the properties of an ideal relativistic gas of events possessing Bose-Einstein statistics. We find that the mass spectrum of such a system is bounded by $\mu \leq m\leq 2M/\mu _K,$ where $\mu $ is the usual chemical potential, $M$ is an intrinsic dimensional scale parameter for the motion of an event in space-time, and $\mu _K$ is an additional mass potential of the ensemble. For the system including both particles and antiparticles, with nonzero chemical potential $\mu ,$ the mass spectrum is shown to be bounded by $|\mu |\leq m\leq 2M/\mu _K,$ and a special type of high-temperature Bose-Einstein condensation can occur. We study this Bose-Einstein condensation, and show that it corresponds to a phase transition from the sector of continuous relativistic mass distributions to a sector in which the boson mass distribution becomes sharp at a definite mass $M/\mu _K.$ This phenomenon provides a mechanism for the mass distribution of the particles to be sharp at some definite value.

In 1948, Feynman showed Dyson how the Lorentz force and Maxwell equations could be derived from commutation relations coordinates and velocities. Several authors noted that the derived equations are not Lorentz covariant and so are not the standard Maxwell theory. In particular, Hojman and Shepley proved that the existence of commutation relations is a strong assumption, sufficient to determine the corresponding action, which for Feynman's derivation is of Newtonian form. Tanimura generalized Feynman's derivation to a Lorentz covariant form, however, this derivation does not lead to the standard Maxwell theory either. Tanimura's force equation depends on a fifth ({\it scalar}) electromagnetic potential, and the invariant evolution parameter cannot be consistently identified with the proper time of the particle motion. Moreover, the derivation cannot be made reparameterization invariant; the scalar potential causes violations of the mass-shell constraint which this invariance should guarantee. In this paper, we examine Tanimura's derivation in the framework of the proper time method in relativistic mechanics, and use the technique of Hojman and Shepley to study the unconstrained commutation relations. We show that Tanimura's result then corresponds to the five-dimensional electromagnetic theory previously derived from a Stueckelberg-type quantum theory in which one gauges the invariant parameter in the proper time method. This theory provides the final step in Feynman's program of deriving the Maxwell theory from commutation relations; the Maxwell theory emerges as the ``correlation limit'' of a more general gauge theory, in which it is properly contained., Comment: This is a complete re-write of our paper, using new techniques, with a new section on non-Abelian gauge fields. (36 pages, latex, no figures)

A celebration of Patricia Smith’s distinguished career, the papers presented in this Festschrift focus on a region and research topics that have fascinated and challenged her since her student days. The broad intellectual and geographic range covered by the papers offers a wealth of information and insights into the biology of past and present populations of the Eastern Mediterranean, a region rich in history and human diversity. Contents: 1) The future of physical anthropology (Phillip L. Walker); 2) Dental development and life history in primates and a comparison of cuspal enamel growth trajectories in a specimen of homo erectus from Java (Sangiran s7-37), a Neanderthal (Tabun c1), and an early homo sapiens specimen (Skhul ii), from Israel (M. Christopher Dean); 3) Were there Neanderthals in the Levant? (Silvana Condemi); 4) Dental development and pathology from the Levantine Middle Palaeolithic: evidence from the Kebara and Qafzeh hominids (Anne-Marie Tillier ); 5) Tooth components in archaic homo sapiens/Neanderthal specimens from Israel and their taxonomic affiliation (Uri Zilberman); 6) Dental attrition: Neanderthals, Romans and Egyptians, and the question of where we go now (Don Brothwell); 7) A final Natufian population: health and burial status at Eynan-Mallaha (Fanny Bocquentin); 8) Morbidity and mortality in the late PPNB populations from Basta and Ba'ja (Jordan) (Michael Schultz, Tyede H. Schmidt-Schultz, Julia Gresky, Kerstin Kreutz, Margit Berner); 9) “What ceremony else?” Taphonomy and the ritual treatment of the dead in the pre-pottery Neolithic b mortuary complex at Kfar Hahoresh, Israel (Tal Simmons, Nigel Goring-Morris and Liora Kolska Horwitz); 10) Is house 12 at Bouqras a charnel house? (Deborah C. Merrett and Christopher Meiklejohn); 11) Times of stress at Çatalhöyük (Theya Molleson); 13) Artificial cranial deformation in the aceramic Neolithic Near East: evidence from Cyprus (Françoise Le Mort); 14) A retrospective view of cauterization: evidence from Anatolia (Metin Özbek); 15) Inter-group variation in long bone morphology: an osteometric and radiological study of past populations of Israel (Leonor Dujovny); 16) Human remains from the Nahal Tzeelim Cave, the Dead Sea area (Baruch Arensburg); 17) The EB IA burials of Bâb Edh-Dhrâ, Jordan: bioarchaeological evidence of metabolic disease (Donald J. Ortner, Evan M. Garofalo, Molly K. Zuckerman); A Roman-Byzantine population from Ghiv'at Shappira, Jerusalem (Israel) (Baruch Arensburg and Anna Belfer-Cohen); 18) Challenges in the study of health and disease in the Crusaders (Piers D. Mitchell); 19) The evidence for tuberculosis in the eastern Mediterranean: past and current research, and future prospects (Charlotte Roberts and Jane Buikstra); 20) The emergence of the zoonotic pathogens in the southern Levant (Gila Kahila Bar-Gal and Charles L. Greenblatt); 21) Bones, teeth and ancient DNA unravel major issues in Levantine bio-history (Israel Hershkovitz and Mark Spigelman); 22) From physical anthropology to molecular genetics: studies of Israeli populations in the 20th century (Batsheva Bonne-Tamir); 23) The genetic history of populations in the southern levant as revealed by y chromosome polymorphisms (Almut Nebel, Dvora Filon, Ariella Oppenheim and Marina Faerman); 24) Forensic anthropology in Israel (Tzipi Kahana and Jehuda Hiss).