Particle spectra and efficiency in nonlinear relativistic shock acceleration: survey of scattering models

We include a general form for the scattering mean free path in a nonlinear Monte Carlo model of relativistic shock formation and Fermi acceleration. Particle-in-cell (PIC) simulations, as well as analytic work, suggest that relativistic shocks tend to produce short-scale, self-generated magnetic turbulence that leads to a scattering mean free path (mfp) with a stronger momentum dependence than the mfp ~ p dependence for Bohm diffusion. In unmagnetized shocks, this turbulence is strong enough to dominate the background magnetic field so the shock can be treated as parallel regardless of the initial magnetic field orientation, making application to gamma-ray bursts (GRBs), pulsar winds, Type Ibc supernovae, and extra-galactic radio sources more straightforward and realistic. In addition to changing the scale of the shock precursor, we show that, when nonlinear effects from efficient Fermi acceleration are taken into account, the momentum dependence of the mfp has an important influence on the efficiency of cosmic-ray production as well as the accelerated particle spectral shape. These effects are absent in nonrelativistic shocks and do not appear in relativistic shock models unless nonlinear effects are self-consistently described. We show, for limited examples, how the changes in Fermi acceleration translate to changes in the intensity and spectral shape of gamma-ray emission from proton-proton interactions and pion-decay radiation.Comment: Accepted for publication in MNRA

Informational Cronyism

If Maher Kara, the Citigroup analyst at the center of the Salman case now before the Supreme Court, was forbidden under SEC Rule 10b-5 from trading securities for his own account while in possession of the valuable secrets to which his job gave him access, should he instead be able to give that information to family members simply in order to enrich them? I suspect that to anyone unfamiliar with the fine line drawing of federal insider trading law, the answer is clearly no. There is probably no more common form of corruption than generously shoveling the fruits of power and privilege to family and close friends. Cultures lacking a strong rule of law make it an art form

Disasters and Disclosures

Many securities fraud lawsuits follow corporate disasters of some sort or another, claiming that known risks were concealed prior to the crisis. Yet for a host of doctrinal, pragmatic and political reasons, there is no clear-cut duty to disclose these risks. The SEC has imposed a set of requirements that sometimes forces risk disclosure, but does so neither consistently nor adequately. Courts in 10b-5 fraud-on-the-market cases, in turn, have made duty mainly a matter of active rather than passive concealment and thus, literally, wordplay: there is no fraud-based duty to disclose risks unless and until the issuer has said enough to put the particular kind of risk “in play.” But when that is, and why, flummoxes them. This incoherence could be rationalized by a more thoughtful assessment of how words matter to investors and better appreciation of the variable role that managerial credibility plays in the process of disclosure and interpretation, which is the main focus of this article. Disasters are an ideal, if disturbing, setting for thinking through the micro-structure of corporate discourse—the implicit rules of interpretation for how marketplace actors interpret what issuers say and don’t say, whether in formal SEC disclosures, conference calls, press conferences and even executive tweets. But even if there is more thoughtfulness to the endeavor, it is fair to ask why wordplay should make so much of a difference as to duty in the first place, or whether instead our impoverished conception of duty and its links to scienter, reliance and causation deserve a more thorough makeover. The study of disasters and disclosures also offers a distinctive reference point for thinking about contemporary controversies associated with bringing matters of social responsibility (e.g., law abidingness) and sustainability (environmental compliance, cybersecurity, product safety, etc.) into the realm of securities law

Is there a resting frame in the universe? A proposed experimental test based on a precise measurement of particle mass

According to the Special Theory of Relativity, there should be no resting frame in our universe. Such an assumption, however, could be in conflict with the Standard Model of cosmology today, which regards the vacuum not as an empty space. Thus, there is a strong need to experimentally test whether there is a resting frame in our universe or not. We propose that this can be done by precisely measuring the masses of two charged particles moving in opposite directions. If all inertial frames are equivalent, there should be no detectable mass difference between these two particles. If there is a resting frame in the universe, one will observe a mass difference that is dependent on the orientation of the laboratory frame. The detailed experimental setup is discussed in this paper.Comment: 9 pages, 4 figure

Initiation into Christ: Ecumenical Reflections and Common Teachings on Preparation for Baptism

Reviewed Book: Canadian Council of Churches. Initiation into Christ: Ecumenical Reflections and Common Teachings on Preparation for Baptism. Ottawa: Novalis; Winfield, BC: Wood Lake Books, 1992

The witness of the worshiping community: liturgy and the practice of evangelism

Reviewed Book: Senn, Frank C. The witness of the worshiping community: liturgy and the practice of evangelism. New York: Paulist Press, 1993

Confirmation: Origins and Reform

Reviewed Book: Kavanagh, Aidan. Confirmation: Origins and Reform. New York: Pueblo Pub, 1988

Federalism in Corporate/Securities Law: Reflections on Delaware, California, and State Regulation of Insider Trading

In this brief Essay, I offer some thoughts on both the theory and the politics underlying the federalism question. My comments will touch on some of the controversies and also look at a somewhat quieter question, the state regulation of insider trading. Over the course of the last few years, judges in California and Delaware have traveled markedly different routes on questions involving the states\u27 role in regulating insider trading. A California court of appeal has recently expanded the reach of the state insider trading statute to cover a claim alleging misconduct in California by an executive of a Delaware chartered company. By contrast, Delaware Vice-Chancellor Leo Strine has hinted strongly that Delaware courts should consider getting out of the business of regulating insider trading entirely, notwithstanding a venerable old Delaware case long cited for the proposition that insider trading naturally breaches the fiduciary duty of loyalty. These contrasting approaches make a nice pair from which to think through the federalism question free from the blinding glare of controversy surrounding Eliot Spitzer, the shareholder ballot access proposal, or Sarbanes-Oxley

Foreword: Revisiting Gilson and Kraakman’s Efficiency Story

Gilson and Kraakman\u27s ‘Mechanisms of Market Efficiency’ is part of the canon of modem corporate law scholarship, one of a handful of articles that has profoundly influenced the way we think about the field. It is also enigmatic, warranting a fresh look by those who think they know what it says from some long-ago reading or second-hand references by other authors

Homeward bound: messages about life after death

Reviewed Book: Warlick, Harold L. Homeward bound: messages about life after death. Lima, Ohio: CSS Pub, 1991. Studies in antiquity and Christianity