The integral cohomology rings of some p-groups

We determine the integral cohomology rings of an infinite family of p-groups, for odd primes p, with cyclic derived subgroups. Our method involves embedding the groups in a compact Lie group of dimension one, and was suggested by P H Kropholler and J Huebschmann

The Boundaries of Safety: The Sanctuary Movement in the Inland Empire

The Trump administration for many represented drastic ideological shift in American values, and for others he embodied a social threat to their lives. In response, many cities, counties, states, and schools proclaimed themselves Sanctuaries to protect their undocumented immigrant community members. The term evokes images of churches operating as a place of refuge with impenetrable walls. The declaration of Sanctuary provided an illusion of boundaries and a sense of safety. This dissertation interrogates the meanings of sanctuary and how the Inland Empire in Southern California, implemented and created sanctuary. By analyzing the California Values Act and working alongside organizers in the Inland Empire, this research identifies barriers in developing sanctuary in this region. This dissertation answers the research question of the implementation and practice of sanctuary utilizing community-based research methods to investigate sanctuary in the Inland Empire. I worked alongside the leading grassroots organizations that developed, trained, and coordinated sanctuary practices for the region. Through functioning participation, semi-structured interviews with activists and previously detained individuals, and community projects; I saw first-hand the barriers and resiliency of communities advocating for immigrant rights and walked alongside those directly impacted by detention. The epicenter of the research and sanctuary organizing is and was Adelanto Detention Facility, the largest for-profit facility on the west coast. Ultimately, the research affirms the need for an abolitionist sanctuary, a movement that is intersectional with Black Lives Matter, end of policing, and the abolition of all forms of incarceration. Without an intersectional movement, justice for immigrants is unattainable because of the immigration systems entanglement with other oppressive systems that marginalize a vast array of social communities in the US. Building on the literature of migration studies, this research unveils the logics and systems of domination that frame belonging. The logics of domination and systems of violence are a result of the US empire-state that shapes migration and US migration policies today. The culmination of these methods offered a deep analysis of the structures of US empire-state, belonging, and sanctuary

The Calcium Triplet metallicity calibration for galactic bulge stars

We present a new calibration of the Calcium II Triplet equivalent widths versus [Fe/H], constructed upon K giant stars in the Galactic bulge. This calibration will be used to derive iron abundances for the targets of the GIBS survey, and in general it is especially suited for solar and supersolar metallicity giants, typical of external massive galaxies. About 150 bulge K giants were observed with the GIRAFFE spectrograph at VLT, both at resolution R~20,000 and at R~6,000. In the first case, the spectra allowed us to perform direct determination of Fe abundances from several unblended Fe lines, deriving what we call here high resolution [Fe/H] measurements. The low resolution spectra allowed us to measure equivalent widths of the two strongest lines of the near infrared Calcium II triplet at 8542 and 8662 A. By comparing the two measurements we derived a relation between Calcium equivalent widths and [Fe/H] that is linear over the metallicity range probed here, -1<[Fe/H]<+0.7. By adding a small second order correction, based on literature globular cluster data, we derived the unique calibration equation [Fe/H]$_{CaT} = -3.150 + 0.432W' + 0.006W'^2$, with a rms dispersion of 0.197 dex, valid across the whole metallicity range -2.3<[Fe/H]<+0.7.Comment: Accepted for publication in A&

Scanning tunneling spectroscopic studies of the pairing state of cuprate superconductors

Quasiparticle tunneling spectra of both hole-doped (p-type) and electron-doped (n-type) cuprates are studied using a low-temperature scanning tunneling microscope. The results reveal that neither the pairing symmetry nor the pseudogap phenomenon is universal among all cuprates, and that the response of n-type cuprates to quantum impurities is drastically different from that of the p-type cuprates. The only ubiquitous features among all cuprates appear to be the strong electronic correlation and the nearest-neighbor antiferromagnetic Cu2+-Cu2+ coupling in the CuO2 planes

Effective gravity from a quantum gauge theory in Euclidean space-time

We consider a $SO(d)$ gauge theory in an Euclidean $d$-dimensional space-time, which is known to be renormalizable to all orders in perturbation theory for $2\le{d}\le4$. Then, with the help of a space-time representation of the gauge group, the gauge theory is mapped into a curved space-time with linear connection. Further, in that mapping the gauge field plays the role of the linear connection of the curved space-time and an effective metric tensor arises naturally from the mapping. The obtained action, being quadratic in the Riemann-Christoffel tensor, at a first sight, spoils a gravity interpretation of the model. Thus, we provide a sketch of a mechanism that breaks the $SO(d)$ color invariance and generates the Einstein-Hilbert term, as well as a cosmological constant term, allowing an interpretation of the model as a modified gravity in the Palatini formalism. In that sense, gravity can be visualized as an effective classical theory, originated from a well defined quantum gauge theory. We also show that, in the four dimensional case, two possibilities for particular solutions of the field equations are the de Sitter and Anti de Sitter space-times.Comment: 20 pages; Final version accepted for publication in Class.Quant.Gra

Dissipative Dynamics of Collisionless Nonlinear Alfven Wave Trains

The nonlinear dynamics of collisionless Alfven trains, including resonant particle effects is studied using the kinetic nonlinear Schroedinger (KNLS) equation model. Numerical solutions of the KNLS reveal the dynamics of Alfven waves to be sensitive to the sense of polarization as well as the angle of propagation with respect to the ambient magnetic field. The combined effects of both wave nonlinearity and Landau damping result in the evolutionary formation of stationaryOA S- and arc-polarized directional and rotational discontinuities. These waveforms are freqently observed in the interplanetary plasma.Comment: REVTeX, 6 pages (including 5 figures). This and other papers may be found at http://sdphpd.ucsd.edu/~medvedev/papers.htm

Electrostatic Decay of Plasma Turbulence

The study of the evolution of a suprathermal electron beam traveling through a background plasma is relevant for the physics of solar flares and their associated type III solar radio bursts. As they evolve guided by the coronal magnetic field-lines, these beams generate Langmuir turbulence. The beam-generated turbulence is in turn responsible for the emission of radio photons at the second harmonic of the local plasma frequency, which are observed during type III solar radio bursts. To generate the radio emission, the beam-aligned Langmuir waves must coalesce, and therefore a process capable of re-directioning the turbulence in an effective fashion is required. Different theoretical models identify the electrostatic (ES) decay process L1 -> L2 + S (L: Langmuir wave; S: Ion-acoustic wave) as the re-directioning mechanism for the L waves. Two different regimes have been proposed to play a key role: the back-scattering and the diffusive (small angle) scattering. This paper is a comparative analysis of the decay rate of the ES decay for each regime, and of the different observable characteristics that are expected for the resulting ion-acoustic waves.Comment: 14 pages, 8 Figures. AAS LaTeX Macros v5.0. To appear in The Astrophysical Journa

Particle-in-cell simulations of circularly polarised Alfvén wave phase mixing: A new mechanism for electron acceleration in collisionless plasmas

In this work we used Particle-In-Cell simulations to study the interaction of circularly polarised Alhén waves with one dimensional plasma density inhomogeneities transverse to the uniform magnetic field (phase mixing) in collisionless plasmas. In our preliminary work we reported discovery of a new electron acceleration mechanism, in which progressive distortion of the Alfvén wave front, due to the differences in local Alfvén speed, generates an oblique (nearly parallel to the magnetic field) electrostatic field. The latter accelerates electrons through the Landau resonance. Here we report a detailed study of this novel mechanism, including: (i) analysis of broadening of the ion distribution function due to the presence of Alfvén waves; and (ii) the generation of compressive perturbations due to both weak non-linearity and plasma density inhomogeneity. The amplitude decay law in the inhomogeneous regions, in the kinetic regime, is demonstrated to be the same as in the MHD approximation described by Heyvaerts & Priest (1983, A&A, 117, 220)

Analysis of the environmental performance of life-cycle building waste management strategies in tertiary buildings

At urban level, the generation Municipal Solid Waste and Construction and Demolition Waste is mostly related to the life-cycle of buildings. An evaluation method based on Life Cycle Assessment methodology is presented in this paper to make an analysis of the environmental performance of different life-cycle building waste management strategies in tertiary buildings. As a case study, several waste management strategies considering a tertiary building located in the city of Zaragoza in Spain, are studied. The aim of the case study is to compare the environmental impacts, in terms of Global Warming Potential, of the scenarios proposed focussing on the waste minimisation and avoidance of landfilling of at least 10% for the Municipal Solid Waste generation during a building''s use stage, and Construction and Demolition Waste generated during its construction and end-of-life. In case of Municipal Solid Waste, the results show that when a recovery scenario includes energy recovery from the residual fraction of the mechanical-biological treatment plant in the form of Refuse Derived Fuel, greater benefits in terms of the Global Warming Potential are obtained than with current scenarios of landfill deposition of the residual fraction. On the other hand, in case of Construction and Demolition Waste, a similar situation can be observed in case of an increase of the recovery rates of metals