Mishpat Ivri, Halakhah and Legal Philosophy: Agunah and the Theory of “Legal Sources"

In this paper, I ask whether mishpat ivri (Jewish Law) is appropriately conceived as a “legal system”. I review Menachem Elon’s use of a “Sources” Theory of Law (based on Salmond) in his account of Mishpat Ivri; the status of religious law from the viewpoint of jurisprudence itself (Bentham, Austin and Kelsen); then the use of sources (and the approach to “dogmatic error”) by halakhic authorities in discussing the problems of the agunah (“chained wife”), which I suggest points to a theory more radical than the “sources” theory of law, one more akin to the ultimate phase of the thought of Kelsen (the “non-logical” Kelsen) or indeed to some form of Legal Realism (with which that phase of Kelsen’s thought has indeed been compared)? I finally juxtapose an account based on internal theological resources (a “Jurisprudence of Revelation”). Downloadable at at http://www.biu.ac.il/JS/JSIJ/jsij1.html

The D coefficient in neutron beta decay in effective field theory

In this paper we explore the time-reversal-odd triple-correlation coefficient in neutron beta decay, the so-called "D coefficient", using heavy-baryon effective field theory with photon degrees of freedom. We find that this framework allows us to reproduce the known results for the contribution which comes from final-state interactions, and also to discuss higher-order corrections. In particular we are able to show that in the heavy-baryon limit all electromagnetic contributions vanish. By calculating the leading correction to the known result, we give a final expression which is accurate to better than 1%. Hence we extend downwards the range over which the D coefficient could be used to explore time-violation from new physics.Comment: 12c pages, 3 eps figures Version accepted for publication in Physics Letters B; minor changes of wordin

Peripheral Nucleon-Nucleon Phase Shifts and Chiral Symmetry

Within the one-loop approximation of baryon chiral perturbation theory we calculate all one-pion and two-pion exchange contributions to the nucleon-nucleon interaction. In fact we construct the elastic NN-scattering amplitude up to and including third order in small momenta. The phase shifts with orbital angular momentum $L\geq2$ and the mixing angles with $J\geq2$ are given parameterfree and thus allow for a detailed test of chiral symmetry in the two-nucleon system. We find that for the D-waves the $2\pi$-exchange corrections are too large as compared with empirical phase shifts, signaling the increasing importance of shorter range effects in lower partial waves. For higher partial waves, especially for G-waves, the model independent $2\pi$-exchange corrections bring the chiral prediction close to empirical NN phase shifts. We propose to use the chiral NN phase shifts with $L\geq 3$ as input in a future phase shift analysis. Furthermore, we compute the irreducible two-pion exchange NN-potentials in coordinate space. They turn out to be of van-der-Waals type, with exponential screening of two-pion mass range.Comment: 30 pages, TeX,12 figures in ps , submitted to Nucl. Phys.

Neutron beta decay in effective field theory

Radiative corrections to the lifetime and angular correlation coefficients of neutron beta-decay are evaluated in effecitive field theory. We also evaluate the lowest order nucleon recoil corrections, including weak-magnetism. Our results agree with those of the long-range and model-independent part of previous calculations. In an effective theory the model-dependent radiative corrections are replaced by well-defined low-energy constants. The effective field theory allows a systematic evaluation of higher order corrections to our results to the extent that the relevant low-energy constants are known.Comment: 13 pages, 1 figure; two references added, minor correctio

Dynamic expression of ancient and novel molluscan shell genes during ecological transitions

Background: The Mollusca constitute one of the most morphologically and ecologically diverse metazoan phyla, occupying a wide range of marine, terrestrial and freshwater habitats. The evolutionary success of the molluscs can in part be attributed to the evolvability of the external shell. Typically, the shell first forms during embryonic and larval development, changing dramatically in shape, colour and mineralogical composition as development and maturation proceeds. Major developmental transitions in shell morphology often correlate with ecological transitions (e.g. from a planktonic to benthic existence at metamorphosis). While the genes involved in molluscan biomineralisation are beginning to be identified, there is little understanding of how these are developmentally regulated, or if the same genes are operational at different stages of the mollusc's life. Results: Here we relate the developmental expression of nine genes in the tissue responsible for shell production – the mantle – to ecological transitions that occur during the lifetime of the tropical abalone Haliotis asinina (Vetigastropoda). Four of these genes encode evolutionarily ancient proteins, while four others encode secreted proteins with little or no identity to known proteins. Another gene has been previously described from the mantle of another haliotid vetigastropod. All nine genes display dynamic spatial and temporal expression profiles within the larval shell field and juvenile mantle. Conclusion: These expression data reflect the regulatory complexity that underlies molluscan shell construction from larval stages to adulthood, and serves to highlight the different ecological demands placed on each stage. The use of both ancient and novel genes in all stages of shell construction also suggest that a core set of shell-making genes was provided by a shared metazoan ancestor, which has been elaborated upon to produce the range of molluscan shell types we see today

Variation in rates of early development in Haliotis asinina generate competent larvae of different ages

<p>Abstract</p> <p>Introduction</p> <p>Inter-specific comparisons of metazoan developmental mechanisms have provided a wealth of data concerning the evolution of body form and the generation of morphological novelty. Conversely, studies of intra-specific variation in developmental programs are far fewer. Variation in the rate of development may be an advantage to the many marine invertebrates that posses a biphasic life cycle, where fitness commonly requires the recruitment of planktonically dispersing larvae to patchily distributed benthic environments.</p> <p>Results</p> <p>We have characterised differences in the rate of development between individuals originating from a synchronised fertilisation event in the tropical abalone <it>Haliotis asinina</it>, a broadcast spawning lecithotrophic vetigastropod. We observed significant differences in the time taken to complete early developmental events (time taken to complete third cleavage and to hatch from the vitelline envelope), mid-larval events (variation in larval shell development) and late larval events (the acquisition of competence to respond to a metamorphosis inducing cue). We also provide estimates of the variation in maternally provided energy reserves that suggest maternal provisioning is unlikely to explain the majority of the variation in developmental rate we report here.</p> <p>Conclusions</p> <p>Significant differences in the rates of development exist both within and between cohorts of synchronously fertilised <it>H. asinina </it>gametes. These differences can be detected shortly after fertilisation and generate larvae of increasingly divergent development states. We discuss the significance of our results within an ecological context, the adaptive significance of mechanisms that might maintain this variation, and potential sources of this variation.</p