Anomalies and large N limits in matrix string theory

We study the loop expansion for the low energy effective action for matrix string theory. For long string configurations we find the result depends on the ordering of limits. Taking $g_s\to 0$ before $N\to\infty$ we find free strings. Reversing the order of limits however we find anomalous contributions coming from the large $N$ limit that invalidate the loop expansion. We then embed the classical instanton solution into a long string configuration. We find the instanton has a loop expansion weighted by fractional powers of $N$. Finally we identify the scaling regime for which interacting long string configurations have a well defined large $N$ limit. The limit corresponds to large "classical" strings and can be identified with the "dual of the 't Hooft limit, $g_{SYM}^2\sim N$.Comment: 13 pages, 1 figure, harvmac.tex, notational errors corrected, references added. Trivial error in section 5 corrected with the result that the domain of validity of the loop expn. is slightly modifie

Looking for Private Information in Self-Assessed Health

The paper investigates whether self-assessed health status (SAH) contains information about future mortality and morbidity, beyond the information that is contained in standard "observable" characteristics of individuals (including pre-existing diagnosed medical conditions). Using a ten-year span of the Canadian National Population Health Survey, we find that SAH does contain private information for future mortality and morbidity. Moreover, we find some evidence that the extra information in SAH is greater at older ages. Many developed countries are experiencing a major shift from defined benefit (DB) to defined contribution (DC) pension arrangements. One consequence of this shift is an effective delay in the age at which workers commit to an annuity. Our results therefore suggest that adverse selection problems in annuity markets could be more severe at older ages, and therefore, that the DB to DC shift may expose workers to greater longevity risk. This is an aspect of the DB to DC shift that has received little attention.Self-Assessed Health, Annuities, Mortality, Morbidity

Looking for Private Information in Self-Assessed Health

The paper investigates whether self-assessed health status (SAH) contains information about future mortality and morbidity, beyond the information that is contained in standard “observable” characteristics of individuals (including pre-existing diagnosed medical conditions). Using a ten-year span of the Canadian National Population Health Survey, we find that SAH does contain private information for future mortality and morbidity. Moreover, we find some evidence that the extra information in SAH is greater at older ages. Many developed countries are experiencing a major shift from defined benefit (DB) to defined contribution (DC) pension arrangements. One consequence of this shift is an effective delay in the age at which workers commit to an annuity. Our results therefore suggest that adverse selection problems in annuity markets could be more severe at older ages, and therefore, that the DB to DC shift may expose workers to greater longevity risk. This is an aspect of the DB to DC shift that has received little attention.Self-Assessed Health, Annuities, Mortality, Morbidity

Use of Surveillance Evidence Under Title III

The rationale offered by Congress for requiring immediate sealing of wiretapping tapes by the court upon the completion of the interception period is to preserve the integrity of the tapes by preventing any tape tampering, alteration, editing, or other governmental bad faith. Congress, however, also added an exception to the sealing requirement that permits disclosure of the tapes\u27 contents in a judicial proceeding if the government has contravened the sealing requirement yet has offered a satisfactory explanation for either a failure to seal or a delay in sealing. No circuit court treats sealing requirement violations in a manner that effects the congressional purpose underlying the sealing requirement. Congress desired to provide an external safeguard against tampering with or manipulating recorded evidence. To preserve this safeguard and the integrity of intercepted communications, courts should interpret section 2518(8)(a) strictly and require a satisfactory explanation for any sealing delay beyond one or two days. Moreover, for purposes of invoking the exception, the court only should deem an explanation satisfactory if the cause for the delay during the initial days of the surveillance is unforeseeable and beyond the government\u27s control. The courts, furthermore, should place an affirmative obligation on the government to show by a preponderance of the evidence that the government preserved the integrity of the tapes during the delay. Because the government initially instituted the electronic surveillance, the court should shift the burden of proof to the government. If the government satisfies these conditions to explain the sealing delay, then the court should not suppress the tapes for mere technical violation of the sealing requirement. Alternatively, the court should suppress the evidence if the government does not satisfy the necessary preconditions explaining the sealing delay

Asset, Burden, Cultybraggan : Community site ownership in a Scottish village

Peer reviewe

Assessing Potential Shale Gas Impacts on Groundwater Resources: Recommendations for Groundwater Monitoring and Definition of Baseline Conditions

Exploitation of shale gas by hydraulic fracturing (fracking) is highly controversial and concerns have been raised regarding induced risks from this extraction technique. The SHEER project, an EU Horizon 2020-funded project, is developing best practice to understand, prevent and mitigate the potential short- and long-term environmental impacts and risks of shale gas exploration and exploitation. Three major potential impacts were identified: groundwater contamination, air pollution and induced seismicity. This presentation will deal with the hydrogeological aspect. As part of the SHEER project, baseline and operational groundwater monitoring was carried out at an extraction site in Wysin, Northern Poland. Baseline monitoring was carried out from December 2015 to June 2016 in four monitoring wells intercepting the main drinking water aquifer located in Quaternary sediments. Fracking operations occurred in two deviated horizontal wells in June and July 2016. Monitoring continued for 1.5 years post-fracking although no significant gas production occurred during this period. Collected data include measurements of groundwater level, electrical conductivity and temperature at 15-min intervals, field measurements of groundwater physico-chemical parameters and frequent sampling for laboratory analyses. Groundwater samples were analysed for a range of constituents including dissolved gases and stable isotopes. This presentation will provide an overview of the monitoring results and the ensuing recommendations for groundwater monitoring in the context of shale gas exploitation. These recommendations relate to: (1) site characterisation prior to any activity, (2) baseline and on-going groundwater monitoring, and (3) relationships between regulators, operators and general public. During the presentation, we will particularly focus on the monitoring methodology and establishing accurate background values for key parameters for baseline monitoring, including suggestions on how to clearly communicate the information to the general public. We will conclude on techniques to identify deviations from baseline values

Scalable Bayesian modeling, monitoring and analysis of dynamic network flow data

Traffic flow count data in networks arise in many applications, such as automobile or aviation transportation, certain directed social network contexts, and Internet studies. Using an example of Internet browser traffic flow through site-segments of an international news website, we present Bayesian analyses of two linked classes of models which, in tandem, allow fast, scalable and interpretable Bayesian inference. We first develop flexible state-space models for streaming count data, able to adaptively characterize and quantify network dynamics efficiently in real-time. We then use these models as emulators of more structured, time-varying gravity models that allow formal dissection of network dynamics. This yields interpretable inferences on traffic flow characteristics, and on dynamics in interactions among network nodes. Bayesian monitoring theory defines a strategy for sequential model assessment and adaptation in cases when network flow data deviates from model-based predictions. Exploratory and sequential monitoring analyses of evolving traffic on a network of web site-segments in e-commerce demonstrate the utility of this coupled Bayesian emulation approach to analysis of streaming network count data.Comment: 29 pages, 16 figure

Entropy Bounds and Dark Energy

Entropy bounds render quantum corrections to the cosmological constant $\Lambda$ finite. Under certain assumptions, the natural value of $\Lambda$ is of order the observed dark energy density $\sim 10^{-10} {\rm eV}^4$, thereby resolving the cosmological constant problem. We note that the dark energy equation of state in these scenarios is $w \equiv p / \rho = 0$ over cosmological distances, and is strongly disfavored by observational data. Alternatively, $\Lambda$ in these scenarios might account for the diffuse dark matter component of the cosmological energy density.Comment: 6 pages, Latex. Added discussion of non-cosmological limits on holographic dark energy. Version to appear in Physics Letters

The Cosmology of String Theoretic Axions

String theory posesses numerous axion candidates. The recent realization that the compactification radius in string theory might be large means that these states can solve the strong CP problem. This still leaves the question of the cosmological bound on the axion mass. Here we explore two schemes for accommodating such light axions in cosmology. In the first, we note that in string theory the universe is likely to be dominated early on by the coherent oscillations of some moduli. The usual moduli problem assumes that these fields have masses comparable to the gravitino. We argue that string moduli are likely to be substantially more massive, eliminating this problem. In such cosmologies the axion bound is significantly weakened. Plausible mechanisms for generating the baryon number density are described. In the second, we point out that in string theory, the axion potentials might be much larger at early times than at present. In string theory, if CP violation is described by a small parameter, the axion may sit sufficiently close to its true minimum to invalidate the bounds.Comment: 24 pages, uses harvmac. Refs corrected plus spellin