A Fresh Catch of Massive Binaries in the Cygnus OB2 Association

Massive binary stars may constitute a substantial fraction of progenitors to supernovae and gamma-ray bursts, and the distribution of their orbital characteristics holds clues to the formation process of massive stars. As a contribution to securing statistics on OB-type binaries, we report the discovery and orbital parameters for five new systems as part of the Cygnus OB2 Radial Velocity Survey. Four of the new systems (MT070, MT174, MT267, and MT734 (a.k.a. VI Cygni #11) are single-lined spectroscopic binaries while one (MT103) is a double-lined system (B1V+B2V). MT070 is noteworthy as the longest period system yet measured in Cyg OB2, with P=6.2 yr. The other four systems have periods ranging between 4 and 73 days. MT174 is noteworthy for having a probable mass ratio q<0.1, making it a candidate progenitor to a low-mass X-ray binary. These measurements bring the total number of massive binaries in Cyg OB2 to 25, the most currently known in any single cluster or association.Comment: Accepted for publication in the Astrophysical Journa

Sub-matrix updates for the Continuous-Time Auxiliary Field algorithm

We present a sub-matrix update algorithm for the continuous-time auxiliary field method that allows the simulation of large lattice and impurity problems. The algorithm takes optimal advantage of modern CPU architectures by consistently using matrix instead of vector operations, resulting in a speedup of a factor of $\approx 8$ and thereby allowing access to larger systems and lower temperature. We illustrate the power of our algorithm at the example of a cluster dynamical mean field simulation of the N\'{e}el transition in the three-dimensional Hubbard model, where we show momentum dependent self-energies for clusters with up to 100 sites

Residual Votes and Abstentions in the 2016 Election

This paper provides a preliminary analysis of the increase in the residual vote rate from 2012 to 2016, when it increased from 0.99% to 1.87% nationwide. It is reasonable to assume that this spike in the residual vote rate is due to a rise in abstentions. However, there are currently other trends in election administration, such as an increasing reliance on vote-by-mail, that could also be driving up the residual vote rate. And, even if the recent up-tick in the residual vote rate is primarily due to an increase in abstentions in 2016, it is not a priori obvious that the source of new abstentions was equally distributed among disaffected Democrats and Republicans. The analysis in this paper relies on a combination of public opinion data and election returns to address these issues. We find, first, that the increase in abstentions in 2016 was most likely due to disaffected Republicans, rather than an across-the-board phenomenon. We also confirm that the increase in the 2016 residual vote rate was not due to changes in voting technologies between 2012 and 2016. We address three issues in the conclusion that this analysis raises: (1) the potential for the growth of protest voting in the U.S., (2) the likelihood that there is a significant under-reporting of voter abstentions in public opinion surveys, leaving a role for aggregate analysis to study this phenomenon, and (3) cautions about the use of the residual vote rate as a metric to gauge the accuracy of voting technologies

Species status and new distribution records for Lithurgus huberi Ducke (Hymenoptera, Megachilidae, Lithurginae)

Notes are provided on the morphology of males and females of the enigmatic Lithurgus huberi Ducke (Lithurginae: Lithurgini), a species historically believed to have been introduced into South America from Asia and to be a possible synonym of the more widespread L. atratus Smith. Distinctive differences are documented between L. huberi and L. atratus, perhaps indicative of separate species. In addition, we provide new records of L. huberi in Argentina and Paraguay.Fil: Gonzalez, Victor Hugo. Oklahoma State University; Estados UnidosFil: Engel, Michael S.. University of Kansas; Estados UnidosFil: Lucia, Mariano. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Entomología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Alvarez, Leopoldo Jesús. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Entomología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Abstention, Protest, and Residual Votes in the 2016 Election

Objective: We analyze the significant increase in the residual vote rate in the 2016 presidential election. The residual vote rate, which is the percentage of ballots cast in a presidential election that contain no vote for president, rose nationwide from 0.99 to 1.41 percent between 2012 and 2016. Method: We use election return data and public opinion data to examine why the residual vote rate increased in 2016. Results: The primary explanation for this rise is an increase in abstentions, which we argue results primarily from disaffected Republican voters rather than alienated Democratic voters. In addition, other factors related to election administration and electoral competition explain variation in the residual vote rates across states, particularly the use of mail/absentee ballots and the lack of competition at the top of the ticket in nonbattleground states. However, we note that the rise in the residual vote rate was not due to changes in voting technologies. Conclusion: Our research has implications for the use of the residual vote as a metric for studying election administration and voting technologies

Finite Black Hole Entropy and String Theory

An accelerating observer sees a thermal bath of radiation at the Hawking temperature which is proportional to the acceleration. Also, in string theory there is a Hagedorn temperature beyond which one cannot go without an infinite amount of energy. Several authors have shown that in the context of Hawking radiation a limiting temperature for string theory leads to a limiting acceleration, which for a black hole implies a minimum distance from the horizon for an observer to remain stationary. We argue that this effectively introduces a cutoff in Rindler space or the Schwarzschild geometry inside of which accelerations would exceed this maximum value. Furthermore, this natural cutoff in turn allows one to define a finite entropy for Rindler space or a black hole as all divergences were occurring on the horizon. In all cases if a particular relationship exists between Newton's constant and the string tension then the entropy of the string modes agrees with the Bekenstein-Hawking formula.Comment: 17 pages, 1 figure, Florida Preprint UFIFT-HEP-94-0

I-Brane Inflow and Anomalous Couplings on D-Branes

We show that the anomalous couplings of $D$-brane gauge and gravitational fields to Ramond-Ramond tensor potentials can be deduced by a simple anomaly inflow argument applied to intersecting $D$-branes and use this to determine the eight-form gravitational coupling.Comment: 8 pages, harvmac, no figure