Possible Implications of Asymmetric Fermionic Dark Matter for Neutron Stars

We consider the implications of fermionic asymmetric dark matter for a "mixed neutron star" composed of ordinary baryons and dark fermions. We find examples, where for a certain range of dark fermion mass -- when it is less than that of ordinary baryons -- such systems can reach higher masses than the maximal values allowed for ordinary ("pure") neutron stars. This is shown both within a simplified, heuristic Newtonian analytic framework with non-interacting particles and via a general relativistic numerical calculation, under certain assumptions for the dark matter equation of state. Our work applies to various dark fermion models such as mirror matter models and to other models where the dark fermions have self interactions.Comment: 20 pages, 6 figure

Who’s Taking Whom: Some Comments and Evidence on the Constitutionality of TELRIC

The FCC requires that the price of unbundled network elements be equal to the total element long-run incremental cost of production plus a reasonable contribution to common and joint costs. This pricing standard has the potential of making the telecommunications market more competitive. TELRIC prices, however, are set independently of historic costs and therefore may not compensate investors for incurred costs. Hence, incumbent local exchange carriers have been fighting its implementation. In all probability, the U.S. Supreme Court will become involved in the debate over its adoption. The Supreme Court has looked at changes in valuation methods in the past. In the abandonment of the fair value doctrine, the Court established criteria to allow a paradigm shift. This Article argues that the same conditions may now exist for TELRIC pricing. Furthermore, the Article presents data that indicates that, to date, no taking has resulted from the use of TELRIC pricing. Hence, the Court is likely to find TELRIC as a viable alternative to historic rate of return pricing

Splitting the Bill: Estimating Personal Consumption in Case of Wrongful Death

In cases of wrongful death, the decedent’s survivors may sue alleged responsible parties for lost financial support. Forensic experts estimate a deceased individual’s personal consumption rate in order to separate the portion of the decedent’s income spent on him- or herself from the amount available as financial support for dependents. This paper enhances the prevailing estimation process by regressing consumption rates over individual households surveyed by the United States Bureau of Labor Statistics in its annual Consumer Expenditure Survey. We contend that this method improves the precision of estimates by accounting for the inherent heterogeneity in consumption among households with otherwise similar characteristics while furthering the methods and purpose which have guided personal consumption estimation for over two decades. In a structure reminiscent of those used by Krueger (2015) and by Patton, Nelson and Lierman (1998), we regress a natural-log-on-natural-log model of personal consumption rate on household income, as well as on the number of dependent children living in the household. The estimated personal consumption rates produced in this analysis are distinctly flatter with respect to income than those of past research using BLS CE microdata. Additionally, the number of children in a household is shown to have greater effect on personal consumption than previously exhibited

The Effects Of The Business Cycle On Oligopoly Coordination: Evidence From The U.S. Aluminum Industry

Haltiwanger and Harrington (1991) among others explore a theoretical study on the effects of demand fluctuations on the degree of oligopoly coordination.  They specify that demand movements are deterministic as the assumption of independent, identically distributed demand shocks in each period is excluded.  This paper empirically examines the hypothesis implied by the Haltiwanger and Harrington in which current prices and margins vary directly with expected future demand.  We also explore the time series properties of demand shocks.  Various lag structures are introduced into the estimation.  The model is applied to the U.S. aluminum industry.  Results support the predictions of the theoretical models

Tensor Coordinates in Noncommutative Mechanics

A consistent classical mechanics formulation is presented in such a way that, under quantization, it gives a noncommutative quantum theory with interesting new features. The Dirac formalism for constrained Hamiltonian systems is strongly used, and the object of noncommutativity ${\mathbf \theta}^{ij}$ plays a fundamental rule as an independent quantity. The presented classical theory, as its quantum counterpart, is naturally invariant under the rotation group $SO(D)$.Comment: 12 pages, Late

Conductivity of Metallic Si:B near the Metal-Insulator Transition: Comparison between Unstressed and Uniaxially Stressed Samples

The low-temperature dc conductivities of barely metallic samples of p-type Si:B are compared for a series of samples with different dopant concentrations, n, in the absence of stress (cubic symmetry), and for a single sample driven from the metallic into the insulating phase by uniaxial compression, S. For all values of temperature and stress, the conductivity of the stressed sample collapses onto a single universal scaling curve. The scaling fit indicates that the conductivity of si:B is proportional to the square-root of T in the critical range. Our data yield a critical conductivity exponent of 1.6, considerably larger than the value reported in earlier experiments where the transition was crossed by varying the dopant concentration. The larger exponent is based on data in a narrow range of stress near the critical value within which scaling holds. We show explicitly that the temperature dependences of the conductivity of stressed and unstressed Si:B are different, suggesting that a direct comparison of the critical behavior and critical exponents for stress- tuned and concentration-tuned transitions may not be warranted

Charge Berezinskii-Kosterlitz-Thouless transition in superconducting NbTiN films

A half-century after the discovery of the superconductor-insulator transition (SIT), one of the fundamental predictions of the theory, the charge Berezinskii-Kosterlitz-Thouless (BKT) transition that is expected to occur at the insulating side of the SIT, has remained unobserved. The charge BKT transition is a phenomenon dual to the vortex BKT transition, which is at the heart of the very existence of two-dimensional superconductivity as a zero-resistance state appearing at finite temperatures. The dual picture points to the possibility of the existence of a superinsulating state endowed with zero conductance at finite temperature. Here, we report the observation of the charge BKT transition on the insulating side of the SIT, identified by the critical behavior of the resistance. We find that the critical temperature of the charge BKT transition depends on the magnetic field exhibiting first the fast growth and then passing through the maximum at fields much less than the upper critical field. Finally, we ascertain the effects of the finite electrostatic screening length and its divergence at the magnetic field-tuned approach to the superconductor-insulator transition.Comment: 9 pages, 6 figure

Scaled penalization of Brownian motion with drift and the Brownian ascent

We study a scaled version of a two-parameter Brownian penalization model introduced by Roynette-Vallois-Yor in arXiv:math/0511102. The original model penalizes Brownian motion with drift $h\in\mathbb{R}$ by the weight process ${\big(\exp(\nu S_t):t\geq 0\big)}$ where $\nu\in\mathbb{R}$ and $\big(S_t:t\geq 0\big)$ is the running maximum of the Brownian motion. It was shown there that the resulting penalized process exhibits three distinct phases corresponding to different regions of the $(\nu,h)$-plane. In this paper, we investigate the effect of penalizing the Brownian motion concurrently with scaling and identify the limit process. This extends a result of Roynette-Yor for the ${\nu<0,~h=0}$ case to the whole parameter plane and reveals two additional "critical" phases occurring at the boundaries between the parameter regions. One of these novel phases is Brownian motion conditioned to end at its maximum, a process we call the Brownian ascent. We then relate the Brownian ascent to some well-known Brownian path fragments and to a random scaling transformation of Brownian motion recently studied by Rosenbaum-Yor.Comment: 32 pages; made additions to Section